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nervousangeltyphoon · 3 years
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Enabling a circular economy for chemicals in plastics
Enabling a circular economy for plastics in Europe and beyond is an ambitious goal. To reach a fully closed loop, numerous challenges and knowledge gaps need to be overcome. This review provides a list of more than 6000 chemicals reported to be found in plastics and an overview of the challenges and gaps in assessing their impacts on the environment and human health along the life cycle of plastic products. We further identified 1518 plastic-related chemicals of concern, which should be prioritized for substitution by safer alternatives. At last, we propose five policy recommendations, including the need of a global and overarching regulatory framework for plastics and related chemicals, in support of a circular economy for plastics and of target 12.4 of the UN Sustainable Development Goals.
State of knowledge of chemicals in plastics
Overview of chemical additives
The production of chemicals for plastics is continuously increasing in terms of both quantity and diversity, with several thousand chemicals used across many material applications. Estimating global additives production is not an easy task, because these data are usually not publicly available. However, with a global plastic production of 368 Mt in 2019, and assuming 1–10% additives mass fraction for nonfibre plastics, the total amount of additives used in 2019 might be around 20 (3.6–36.8) Mt. If plastic production follows current increasing trends, it is estimated that we will have produced 2000 Mt of additives by the end of 2050. Plasticizers are the most used additives and together with flame retardants cover almost 50% of globally applied additives. Owing to their wide-ranging application and high-production volumes, these two types of additives have been receiving special attention (e.g. Commission Regulation (EU) 2018/2005).
Additives are applied during the production process at different concentrations based on the specific function that they need to fulfil. It provides an overview of functions, typical material application, chemical classes, and application ranges. For example, plasticizer application ranges vary across materials, and can reach up to 60–70% of the plastic mass in soft PVC resin products. Other additives are usually applied at much lower concentrations, such as 0.7–25% for flame retardants or 0.05–5% for stabilizers and antioxidants. The concentration of unintentional residues is typically <1%. Generally, it is accepted to consider as NIAS only compounds with a mass <1000 Da, assuming that substances with a higher molecular weight cannot be absorbed in the body (EU No 10/2011, although there might be some uptake in the gut).
Chemicals reported in plastics
As of today, there is no publicly available database containing a complete and detailed list of chemicals used in the various plastic products, specifying typical function, plastic types, and mass fraction ranges. In an attempt to provide such an overview, we used the mapping of plastic additives conducted by the European Chemical Agency (ECHA), and expanded it with data from 35 additional sources. The considered sources include—amongst others—Annex I of Commission Regulation (EU) No 10/2011, also called the Union list, which is a positive list of monomers and additives authorized for use in plastic-based food contact materials, the work conducted by Groh et al., and the Chemicals and Product Categories database (CPCat; actor.epa.gov/cpcat), which contains information across different categories and materials
As a result, It provides a list of more than 6000 functional additives, pigments and other substances found (both currently and in the past) in plastics. For each substance, we provide CAS number, main chemical function, typical application range, and polymer type (when available). For building the data set, we checked and harmonized where needed the reported chemical names, CAS numbers, and functions. Chemicals were classified according to their specific function in plastic materials based on the information reported in the considered sources. Wherever such information was missing, we retrieved the function from other references.
It aims at providing a comprehensive overview of chemicals found in plastics across different polymers and product applications. It contains various types of substances reported to be found in plastics; consequently, it is not limited to additives but also includes NIAS, solvents, unreacted monomers, starting substances, and processing aids.
Challenges and gaps in assessing plastic-related chemicals’ impacts in a circularity context
The goal of a circular economy is to move.
Sodium carbonate, activated carbon and copper-impregnated aluminium are used to absorb the sulphur without the use of water. They give efficiencies of absorption of 85–90% and have the advantage of not cooling the stack gases. The gases will then rise upwards from the top of the stack and disperse more widely in the atmosphere.
Food packaging is of high societal value because it conserves and protects food, makes food transportable and conveys information to consumers. It is also relevant for marketing, which is of economic significance. Other types of food contact articles, such as storage containers, processing equipment and filling lines, are also important for food production and food supply. Food contact articles are made up of one or multiple different food contact materials and consist of food contact chemicals. However, food contact chemicals transfer from all types of food contact materials and articles into food and, consequently, are taken up by humans. Here we highlight topics of concern based on scientific findings showing that food contact materials and articles are a relevant exposure pathway for known hazardous substances as well as for a plethora of toxicologically uncharacterized chemicals, both intentionally and non-intentionally added. We describe areas of certainty, like the fact that chemicals migrate from food contact articles into food, and uncertainty, for example unidentified chemicals migrating into food. Current safety assessment of food contact chemicals is ineffective at protecting human health. In addition, society is striving for waste reduction with a focus on food packaging. As a result, solutions are being developed toward reuse, recycling or alternative (non-plastic) materials. However, the critical aspect of chemicals for food safety is often ignored. Developing solutions for improving the safety of food contact chemicals and for tackling the circular economy must include current scientific knowledge. This cannot be done in isolation but must include all relevant experts and stakeholders. Therefore, we provide an overview of areas of concern and related activities that will improve the safety of food contact articles and support a circular economy. Our aim is to initiate a broader discussion involving scientists with relevant expertise but not currently working on food contact materials, and decision makers and influencers addressing single-use food packaging due to environmental concerns. Ultimately, we aim to support science-based decision making in the interest of improving public health. Notably, reducing exposure to hazardous food contact chemicals contributes to the prevention of associated chronic diseases in the human population.
Titanium dioxide is odourless and absorbent. Its most important function in powder form is as a widely used pigment for lending whiteness and opacity. Titanium dioxide has been used as a bleaching and opacifying agent in porcelain enamels, giving them brightness, hardness, and acid resistance.
We supply innovative specialty chemicals for textile leathe and related industries that include dyes, pretreatment, bleaching, finishing, coating and special effects products. Our commercial and technical teams will provide you with unparalleled sales support to fit your needs and keep you in the loop with the latest market developments.
We provide high quality raw materials, sourced from leading global manufacturers, as well as a wide range of value-added services including formulation advice, lab support, sampling, and professional handling and delivery of your products.
The addition of water treatment chemicals has always been considered as a standard operation in water and wastewater treatment. The concentration of chemicals was usually kept to the minimum necessary to achieve a good quality of potable or otherwise treated water. A significant interruption to the status-quo occurred more than 20 years ago after a severe and highly publicized outbreak of Cryptosporidium parvum oocysts. The strategic planning after the outbreak was to shift from physical-chemical to physical treatment methods, such as membrane filtration and UV disinfection. As such, the new procedures were supposed to eliminate the threat of water contamination through a minor addition of chemicals. Such was the mistrust and disappointment with water treatment chemicals themselves.
Indeed, water treatment technologies, such as chemicals for water treatment, are now using novel physical treatment methods. Membranes largely replaced granular filtration, and UV is paving the way towards minimization or elimination of the use of classic disinfection chemicals, such as chlorine and its derivatives. Yet, far from the “high-tech” revolution in water treatment technologies actually reducing the use of chemicals, the latter has in fact been significantly increased. The “conventional” chemicals used for pre-treatment, disinfection, corrosion prevention, softening and algae bloom depression are all still in place. Furthermore, new groups of chemicals such as biocides, chelating agents and fouling cleaners are currently used to supplement them. These latter are the chemicals needed to protect the high-tech equipment, to optimize the treatment, and to clean the equipment between uses.
The health effects of the new chemicals introduced into water are yet to be fully established. Typically, a higher treatment efficiency requires effective chemicals, yet these are not always environmentally friendly. It seems obvious that the “high-tech” revolution currently affects the sustainability of water resources, and certainly not in a completely positive way. In short, the adverse effects of the introduction of such a significant amount of treatment chemicals into our sources of water are yet to be evaluated.
Employees in printing industries can be exposed to multiple solvents in their work environment, like all sorts of chemicals for paint and print. The objectives of this study were to investigate the critical components of chemical solvents by analyzing the components of the solvents and collecting the Safety data sheets (SDSs), and to evaluate the hazard communication implementation status in printing industries.
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nervousangeltyphoon · 3 years
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Brief on Features and Applications of Solvent Dyes, and The Chemistry of Pigments
The selection of solvent for preparing a working electrode (and to act as the electrolyte) is known to influence the efficiency of dye-sensitized solar cells. In this topical review, results taken from a systematic study are presented from the authors’ own lab examining how protic and aprotic solvents, as well as solvent polarity, affect adsorption of carboxylic dyes on the titanium dioxide nanoparticle surface and electron injection from the dye to the semiconductor. Adsorption of dye molecules on nanoparticle surfaces is measured through second harmonic light scattering and electron injection through ultrafast transient mid-infrared absorption. It is revealed that protic solvents do not allow direct adsorption of the dye onto the semiconductor surface, due to hydrogen bonding with the dye and competitive binding to the semiconductor surface. Aprotic solvents, on the other hand, support solvation of the dye molecules but also facilitate dye adsorption on the semiconductor nanoparticle. Among aprotic solvents, it is found that solvents with higher polarity result in larger adsorption free energy for the dye and faster electron injection. Overall, these studies reveal that aprotic solvents with high solvent polarity (such as acetonitrile) yield more efficient solar cell devices.
The world of dyes and pigments is vast and there are innumerable varieties of these colorants to fulfill the requirements of varied industrial and commercial sectors. Acid dyes, basic dyes, solvent dyes, lake colors, pigment colors are just to name a few from the vast ocean of colors. This article will talk in brief about the solvent dye.
Solvent dye is a dye that is soluble in plastics or organic solvents. When it goes with an organic solvent the dyeing process occurs in a solution. As the molecules of solvent dyes have a very small polarity or none at all there is no ionization involved in the dyeing process as it does, say, with acid dyes. Solvent dyes are normally water insoluble. One commonly used organic solvent with solvent dyes that is non-polar is petrol.
As for the naming of solvent dyes a standardized pattern is followed. In the pattern, the first word is always ‘solvent’ which is followed by the dye color and then a distinguishing number. For example, the varied shades of red are segregated by the distinct number that comes after the shade name like ‘Solvent Red 49’, ‘Solvent Red 1’, and ‘Solvent Red 24’ and so on.  Another example of the shade red occurring in another type of dye is Pigment Red 48 which is an azo derivative from naphthalene.
Solvent dyes are pretty versatile and have found their way into a number of applications. One of their common uses is in the automotive sector to impart color to petrol fuel and other lubricants. Varied hydrocarbon based non-polar materials such as waxes and candles, coatings and wood stains are colored with the aid of solvent dyes. In the printing industry they go towards marking inkjet inks, inks and glass coloration. Textile printing is followed by the media industry where the solvent dyes are used for magazines and newspapers.
Dyeing of plastics is another application which uses solvent dyes because of its chemical compatibility. In the plastics industry these dyes lend color to a number of solid materials like nylon, acetates, polyester, PVC, acrylics, PETP, PMMA, styrene monomers, polystyrene and other fiber. They are also increasingly being used for smoke signaling in the pyrotechnics industry. A mention has to be made of its application in scientific research and medical diagnostics. Here, the solvent dye is used as an important component to produce stains that help in identification of varied components in a cell structure.
There are several advantages offered by solvent dyes that have led to its wide use in varied applications. Color shade consistency, superior light fastness, resistance to migration, good thermal stability, extremely dissolvable in plastics and lack of precipitation even after extensive storage are just to name some of its superior attributes.
However, sourcing solvent dyes from reputed solvent dyes manufacturers is highly important. This guarantees you the quality of the product and its effectiveness in the application it shall be used for. There are several reputed manufactures of these dyes and the names can be easily obtained from the online yellow pages.
At the heart of every drop of paint, every thread of cloth, every bit of your brightly colored phone case is a pigment. Pigments are the compounds added to materials to give them color. This deceptively simple application has shaped our perception of the world via art, fashion, and even computer displays and medicine. Pigments are used in paints, inks, plastic applications, fabrics, cosmetics, and food.
Some of the earliest chemistry was to make and isolate pigments for paints, and pigment conservation is a focus for many modern researchers who identify and preserve artwork.
Get to know pigments
But what is a organic pigment, exactly? Pigments are brightly colored, insoluble powders (brightly colored liquids are called dyes). In most cases, the bright color is a result of the material absorbing light in the visible spectrum. In inorganic pigments, this absorption is the result of charge transfer between a metal (transition metals are really good at this); organic pigments tend to have conjugated double bonds that absorb visible wavelengths.
Pigments are mixed with binders to attach them to a substrate. The resulting suspension—a paint—is used to coat materials and impart color onto them. In industry, there are three pigment classes: absorption pigments (used in watercolor paints), metal effect pigments (used to create surface luster), and pearlescent pigments.
Pigments are found in nature, such as ochre (a blend of iron oxides and hydroxides) and indigo (C16H10N2O2). They can also be synthetic pigments such as mauve (an aniline derivative) or white lead. White lead, one of the earliest synthetic pigments, is made by treating sheets of lead with vinegar. They are often more robust than dyes, which dissolve in the material they are coloring. Pigments can keep their color for many centuries and withstand high heat, intense light, and exposure to weather or chemical agents.  
Cataloging colors
Because of their prominence in art, pigments have an important place in history. The Forbes Pigment Collection, housed in the Straus Center for Conservation and Technical Studies at the Harvard Art Museums, catalogs and preserves more than 2,500 pigments. Its founder, Edward Forbes, started the collection by gathering pigment samples from his travels all over the world, including colors like mummy brown, made from ground-up mummies, and carmine red (C22H15AlCaO13), obtained from cochineal insects.
The Forbes Pigment Collection is often used as a reference library to standardize colors and identify pigment samples from artworks, which can confirm or disprove the piece’s origins. For instance, in 2007, a painting supposedly by Jackson Pollock was discovered to be a forgery when chemical analysis revealed the presence of pigments that weren’t available until decades after his death (Custer, 2007).
Furthermore, many artists had personal preferences and favored certain pigments over others. Thus, knowing which pigments were used, and whether they were in character for the artist or not, can help art historians determine an art piece’s authenticity.
The Forbes Pigment Collection, which boasts more than 60 natural samples, also highlights one of the challenges with natural pigments. Natural pigments were gathered from nature, for example, ore deposits, minerals, and flowers. But tiny shifts in chemical composition or particle growth cause specific shades to vary significantly due to impurities present in the sample.
Analyzing and understanding the high performance pigment used in paintings is also vital to artwork restoration and preservation. Many pigments chemically, like coating and paints, react with ambient light and humidity, as well as harsher substances like soot and smoke from cigars or fireplaces. Pigments may oxidize, dissolve in acid or water, undergo phase transitions, react with the binders in the paint, or degrade.
For example, eosin Y was a pigment historically favored by many artists, most notably Vincent van Gogh. Initially a vibrant red, exposure to light gradually turns eosin white as UV radiation excites the pigment molecules and leads to the production of OH radicals. This breaks down the structure of the pigment, and eventually turns it white. Knowing such information allows art historians to better conserve art.
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nervousangeltyphoon · 3 years
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Comparing Castings and Forgings
Many cell types will grow when attached to a rigid surface but not in suspension, a phenomenon termed „anchorage dependence”︁. Anchorage dependence can be studied by incorporating solid particles of varying size into gels. It has been found that colonies will form on glass fibrils 500 μ in length, but not in the presence of silica fragments smaller than the cells. This shows that the suspending medium is not itself inhibitory, and confirms the requirement for a rigid surface of adequate size.
The state of inhibited cells in suspension culture was examined by dispersing them in a methyl cellulose gel, in vessels lined with agar. In this system aggregation is prevented and the cells may be recovered quantitatively. Normal, as well as transformed, cells increase in size, and a proportion synthetize DNA during the first 24 hours in suspension culture. Growth and DNA synthesis in normal cells then virtually cease, while transformed cells continue to grow into colonies. The stationary normal cells remain competent for further growth for at least a week in suspension. When such cells are allowed to attach to a rigid surface in the presence of colchicine, DNA synthesis occurs and is followed by mitosis. These results indicate that suspended cells are blocked between mitosis and the end of the S phase of the cycle.
Anchorage Classification
To anchor is to hold or resist the movement of an object; anchorage is the gaining of that hold. In orthodontics, terms such as “critical anchorage”, “noncritical anchorage”, or “burning anchorage” are often used to describe the degree of difficulty of space closure. Anchorage may be defined as the amount of movement of the posterior teeth (molars, premolars) to close the extraction space (Fig. 10-1A) in order to achieve selected treatment goals. Therefore, the barrier anchorage needs of an individual treatment plan could vary from absolutely no permitted mesial movement of the molars/premolars (or even distal movement of the molars required) to complete space closure by protraction of the posterior teeth.
When designing large structural components it’s critical to make an informed decision between castings and forgings. The following paper by Rexnord provides an in-depth examination.
Material selection is one of the most crucial decisions made in the design, manufacture, and application of large structural components. Material selection naturally influences the entire performance of the design, and thus it is critical that informed decisions are made during the design stage. Steel castings and steel forgings are two alternatives for large structural components. For many design engineers it is often assumed that a forging is a better product because it is formed or worked during the manufacturing process. It also assumed that castings are inferior because they may contain porosity. Nothing could be further from the truth. Each process has its advantages and disadvantages. It is just as possible to produce an inferior product whether it is a forging or a casting. This paper will present an honest evaluation of castings and mining forgings, so that those in the design community can make an informed choice.
Introduction
This paper will concern itself with the differences between forged and cast steels in heavy sections. Heavy sections will be interpreted to mean parts in excess of 10 tons and a minimum metal section of 200 mm (5”). All steel products, whether they are cast or wrought (forged), start from a batch of molten steel that is allowed to solidify in a mold. The difference is that a wrought product is mechanically worked by processes such as rolling or forging after solidification, while a casting is not.
Melt Shop Practice
The process of steel making is essentially the same for both wrought and cast steels. Liquid steel is principally an alloy of iron and carbon. Other metals such as chromium, nickel, manganese, and molybdenum are added as alloying agents to impart particular properties to the steel. The raw materials used to make steel also contain undesirable elements such as phosphorus and sulfur, which form inclusions in the steel that can never be completely removed from the steel. Thus the quality of both forgings and castings is dependent upon the quality of the molten steel that is poured into the mold.
Since most forge shops purchase their steel ingots, they are dependent upon the steel mill to control the quality of the raw material that is used in their product. This also limits forge shops to supplying the standard alloy grades that the steel mill offers. Conversely, steel foundries have to both make and pour their own steel to produce a casting, and thus have full control of the metal that is used to produce the casting. This also allows the foundry to supply virtually any alloy grade that the customer may want.
Liquid steel has a high affinity for oxygen, and it will form oxide inclusions that can also become trapped in the final product. Molten steel must be handled properly to minimize the formation of re-oxidation products. Once the steel is refined in the melting furnace it is tapped into a ladle, which is a refractory lined vessel made to handle molten steel. Good steel making practice dictates the use of a bottom pouring ladle. The reason for this is that a slag layer is developed on top of the molten steel by use of fluxes. This slag layer is less dense than steel, and thus floats on top while at the same time forming a protective barrier from the atmosphere. This protective barrier is maintained since the steel is poured from the bottom of the ladle. The bottom pouring technique is used for both steel castings and for steel ingots.
One important distinction between wrought and cast steels is the de-oxidation practice that is used. Wrought steels are typically “aluminum killed,” which means that a small amount of aluminum is added during the melting process for the purpose of removing oxygen from the steel. While very effective at removing oxygen, the aluminum forms microscopic aluminum oxide particles, which are abrasive during the CNC machining process. Some steel casting shops de-oxidize with calcium, which also removes the oxygen but produces a softer, more machinable inclusion.
Forging
Process
Wrought or forged materials by definition are made from cast ingots, which are then mechanically worked after solidification. Ingot castings are the raw materials from which all wrought products such as forgings, plate, and barstock are produced, and they are nothing more than a casting that is produced by pouring the liquid steel into a reusable metal mold. The cast ingot structure consists of different zones that contain porosity and segregation.
After solidification the ingot is hot forged into the desired shape using a hammer, press, or ring-rolling machine. As the forging is hot worked into shape, the inclusions, porosity, and grains within the steel ingot are forced to flow in the direction the part is being worked. This imparts directionality to the finished part. According to the forging industry, this grain flow makes forgings superior to castings. However, the fact is that although the mechanical properties of a forging are higher in the longitudinal direction (direction of working), they are significantly lower in the transverse direction, or perpendicular to the grain flow. Thus, when using a forging the design engineer needs to evaluate the loading characteristics in both the transverse and longitudinal direction.
Large forgings are hammered or pressed into rough shapes, which then require extensive machining parts or welding to other components to produce a more complex shape. This adds to the cost of the overall product. Large forgings are limited as to the amount of mechanical working that can be done.
The forging industry typically refers to the term “reduction ratio,” which is the ratio of cross-sectional area before and after forging and is used as a means to specify the quality of the forging. The typical standard for very large forgings is to require a minimum of three reductions. It is recognized by the forging industry that excess hot working can impart too much directionality into the part.
Forgings are subject to process variables and have the same potential for defects as any manufacturing process. For example, a large forging may actually burst or crack internally during forging if not heated properly
Casting
Process
Most steel mining castings are produced in expendable sand molds. The mold is produced by forming sand around a pattern, which is a replica of the finished part. Molding sands are mixed with materials that will allow it to hold the desired shape after the pattern is removed. Holes or cavities are created by assembling sand cores in the mold. The pattern equipment also includes the gates and risers which are needed to produce a quality casting. The gating system is designed to allow the metal to flow into the mold in a controlled manner. Risers are reservoirs of molten metal which allow the casting to solidify without shrinkage porosity.
Post solidification processing includes sand removal or shakeout, removal of gates and risers, inspection, weld upgrading, and heat treatment. The main advantage of the casting process is its versatility. Castings are best suited for complex geometries that cannot be easily produced by the forging process.
The principal difference between a casting and a forging is that the final part shape is created when the molten metal solidifies in the mold. Since the sand mold produces the desired finished shape, all that remains is to process the casting through various finishing operations in the foundry. This processing does not alter the directionality of the casting. A steel casting is homogenous. This means that the mechanical properties of a casting are the same regardless of the direction of applied stresses.
It is very important to understand the underlying principles that dictate how a casting solidifies. As steel cools in the mold it naturally changes from a liquid to a solid, resulting in volumetric contraction. Additional feed metal in the form of risers must be supplied to the casting to make up for this loss in volume. There also needs to be a pathway for the additional metal to feed the casting as it solidifies. If a region of a casting is isolated from the riser, a shrinkage cavity will form. In this case it is necessary to add material to allow the molten metal to be properly fed from the molten riser.
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nervousangeltyphoon · 3 years
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A Buyer's Guide to LED Tube Lights
Replacing your fluorescent tube lights with LED retrofits can be a confusing and daunting process. We've put together this guide to demystify all of the ins and outs of replacing your fluorescent tubes with LED tube lights.
1) Advantages of LED tubes over fluorescent tubes The many advantages of LED tubes over fluorescents are covered quite extensively, so we won't go into depth, but the three primary advantages are:
Higher efficiency, energy savings (up to 30-50%)
Longer lifetimes (typically 50k hours)
No mercury
2) Fluorescent tubes sizes and LED tube light retrofitting Because fluorescent fixtures are often mounted into ceilings and connected directly to mains electricity, they are relatively expensive and difficult to replace completely. As a result, it oftentimes makes the most economical sense to simply use the same fluorescent fixture, but replace the fluorescent tube with an LED tube light. Therefore, it is important to understand the types of fluorescent tubes that were developed, so that the correct LED panel light can be retrofitted in place. Over the years, fluorescent tube manufacturers developed many varieties of sizes and types.
T8 4-ft: Four-foot T8 fluorescent lamps are the most commonly used type today. They are 48 inches in length, and have a 1 inch lamp diameter.
T12 4-ft: Four-foot T12 fluorescent lamps are less efficient compared to T8 lamps. They are the same length as T8 lamps, but have a larger 1.5 inch lamp diameter.
T5 4-ft: Four-foot T5 fluorescent lamps are typically the most efficient, and some of the newest types of lamps introduced in the 2000's in the USA. They are commonly designated T5HO (high output) and provide more brightness than their T8 counterparts. They are slightly shorter than four feet (45.8 inches). T5 lamps come in a variety of lengths such as 1-ft, 2-ft and 3-ft versions and are commonly used in non-ceiling fixtures such as table lamps.
T8 and T12 tubes are also available in other lengths such as 8-ft tubes, but 4-ft lengths remain the most common types. LED tube lights replicate the mechanical dimensions to ensure that they can be true retrofit replacements, and adopt the same form factor names (e.g. 4-foot T8 LED tube light). T8 and T12 fixtures are generally the same length and use the same pins, so mechanically they are usually cross-compatible. T5 fixtures are NOT cross-compatible with T8 and T12 lamps due to their different pin sizes and actual length. 3) Fluorescent ballasts and LED tri-proof light retrofitting All fluorescent tube lights use a device called a ballast to regulate the lamp's brightness as it warms up. These devices are necessary for fluorescent lamps, and differ from incandescent lamps which can be connected directly to mains electrical circuits. Fluorescent lamp fixtures typically house the ballast inside the fixture, and is not accessible without removing the fixture from the ceiling. Alterations to the fluorescent lamp ballast should be done only by those comfortable and knowledgeable with electrical work.
Today LED high bay lights deliver equal or better lighting performance with only a fraction of the energy consumption of the traditional fluorescent tube LED flood lights. LED tube is the newest product line in the tube family made up of white LED chip modules. Provided with the advantages of long life-span, radiation-free, energy saving, environmental friendly.
Once you learn about the benefits of LED tube lights, you will see and understand why they are a positive choice for anyone looking to improve the environment with their lighting choices. In this Article, we will be comparing LED linear Lighting and traditional Fluorescent Tube Light by following characteristics
Function
Light Output
Power Consumption
Directivity
Color
What are LED Tube Lights?
LED tube lights are among the most popular and versatile lighting solutions available today. They’re particularly well suited to applications and install environments where the goal is to achieve a flexible variety of modern, clean-looking indoor lighting in rooms and displays of all sizes.
You’ll often find assemblies of larger LED tube lights being used to provide bright, even lighting across many types of wider or more open spaces. Common examples might include commercial displays, workshops and laboratories, kitchens, hallways, foyers, factory floors, gymnasiums, car parks, and any other communal, multipurpose or high traffic areas.
Smaller LED tubes are also highly popular options for accent lighting in and under cabinets, worktops and other items of built-in or freestanding furniture, as well as in many different types of signage assemblies and other important display areas.
Today, a huge number of homes, business premises and civic facilities are transitioning away from the traditional, older style fluorescent/CFL tube lighting and installing LED alternatives in their place. There are several great reasons to do this, with the most compelling being the lower running costs and far longer lifespans of LED lamps vs fluorescent equivalents. This generally results in vastly improved efficiency throughout the working life of the light. In turn, this ultimately means that you can expect far better value over time, as well as considerably reduced environmental impact, by switching to LEDs.
In this introductory guide, we’ll find out a little more about the different types of LED tube lights you can buy online, as well as briefly looking at how to fit them. We’ll also compare LED tubes to other common types of tube and strip lights, and contrast the relative strengths and weaknesses of each kind.
T5 LED Tube light and T5 Tubes
LED tube lights are usually categorised by various key designations. The most common of these are tube length (this can be stated in either imperial or metric measurements) and bulb or lamp size. Lamp size is typically given as a ‘T’ measurement, with widespread standard sizes including T5, T8 and T12.
If you’re wondering exactly what is the difference between T5, T8 and T12 lights, the main point to remember is that the higher the T rating, the thicker a lamp will be in diameter. T equals 1/8 of an inch and the number after the T denotes how many eighths of an inch wide the bulb is - hence T8 is exactly one inch or 8/8ths. You can use this to calculate the diameter of different sized LED tube lights. Therefore, T8 tubes at 1-inch (25.4mm) have a larger diameter than T5 tubes (5/8-inch or 15.9mm), but they are not as wide as T12 (1.5-inches or 38.1mm) lamps.
In standard fluorescent tubes, smaller diameters almost always mean better efficiency. A T5 bulb will use less energy to produce the same amount of light as a T8, while a T12 will run at about 45% higher electricity consumption to output the same amount of light as a T5. Being vastly more power-efficient across the board, newer LED equivalents don’t follow quite the same pattern in terms of percentages. However, the basic principle remains similar, even if the ratios between bulb diameter and energy usage stay far closer together as you move up the lamp sizing scale.
It's also worth noting that different tube sizes will tend to be associated with different lamp bases or sockets. T8 and T12 tubes are mounted to bi-pin G13 bases as standard, while T5 tubes are normally attached to a bi-pin G5 socket fitting. In simple terms, this is essentially the tube light equivalent of standard bulb cap styles and sizes.
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nervousangeltyphoon · 3 years
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How Does a Drill Bit Work?
A drill bit is what actually cuts into the rock when drilling an oil or gas well. Located at the tip of the drillstring, below the drill collar and the drill pipe, the drill bit is a rotating apparatus that usually consists of two or three cones made up of the hardest of materials (usually steel, tungsten carbide, and/or synthetic or natural diamonds) and sharp teeth that cut into the rock and sediment below.
In contrast to percussion drilling, which consists of continuously dropping a heavy weight in the wellbore to chip away at the rock, rotary drilling uses a electric hammer drill bit to grind, cut, scrape and crush the rock at the bottom of the well. The most popular choice for drilling for oil and gas, rotary drilling includes a drill bit, drill collar, drilling fluid, rotating equipment, hoisting apparatus and prime mover.
The prime mover is the power source for the drilling, while the hoisting equipment handles lifting the drill pipe to either insert it into the well or lift it out of the well. Rotating equipment is what sets the whole system in motion. Before the early 1900s, drilling equipment was spun using livestock and a wooden wheel, but now, the rotating equipment is put in motion by a rotary table, which is connected to a square-shaped hollow stem, called a Kelly. Connected to the Kelly is the drill collar, which puts pressure and weight on the drill bit to make it drill through the rock and sediment. Capping off the drillstring is the drill bit, and encompassing the drilling process is drilling fluid, which helps to provide buoyancy to the drill string, lubricate the drilling process and remove cuttings from the wellbore.
Types Of Drill Bits
There are a number of different types of drill bits. Steel Tooth Rotary Bits are the most common types of drill bits, while Insert Bits are steel tooth bit with tungsten carbide inserts. Polycrystalline Diamond Compact Bits use synthetic diamonds attached to the carbide inserts. Forty to 50 times stronger than steel bits, Diamond Bits have industrial diamonds implanted in them to drill extremely hard surfaces. Additionally, hybrids of these types of drill bits exist to tackle specific drilling challenges.
Various drilling designs are also employed for different results, including core bits, which gather formation cores for well logging; mill bits, which help to remove cuttings from the well; and fishtail bits, which enlarge the drill hole above the drill bit.
Different configurations work better on different formations; so a number of different drill bits may be inserted and used on one well. Additionally, drill bits have to be changed due to wear and tear. Drilling engineers choose the drill bits according to the type of formations encountered, whether or not directional drilling is required, for specific temperatures, and if well logging is being done.
When a drill bit, like a masonry drill bit, has to be changed, the drill pipe (typically in 30-feet increments) is hoisted out of the well, until the complete drill string has been removed from the well. Once the drill bit has been changed, the complete drill string is again lowered into the well.
Cutting metal with
cutting wheel
s
Plenty of manual cutting applications call for a hand-held grinder and cutting wheel. Cutting sheet metal, sizing a piece for fabrication, cutting out a weld to refabricate it, and cutting and notching in pipeline work are just a few examples of what can be accomplished using a grinder and cutting wheel.
Resinoid-bonded cutting wheels are a popular choice to achieve these types of cuts because they offer portability and allow you to cut in many different angles and orientations. The bonding agent, in this case resinoid, holds the wheel together so it can cut effectively. The bond wears away as the abrasive grains wear and are expelled so new sharp grains are exposed.
By following a few best practices, you can extend wheel life, promote safety, and improve productivity and efficiency within the process.
The Basics of Cutting Wheels
The main considerations in using resin cutting wheels include the cutting application, the tool being used—such as a right-angle grinder, die grinder, or chop saw—desired cutting action with diamond saw blade, the material being cut, and space. Wheels typically provide a fast cutting action, long life, and tend to be cost-effective.
The two main types of resinoid-bonded abrasive cutting wheels are Type 1, which are flat, and Type 27, which have a raised hub. Type 1 wheels generally are used for straight-on cutting on electric or pneumatic right-angle grinders or die grinders and chop saws, among other tools. Type 27 wheels are required when there is some type of interference and the wheel needs to be raised up from the base of the grinder, but personal preference also plays a role in the decision. They are most commonly used with electric or pneumatic right-angle grinders.
Resinoid-bonded abrasive cutting wheels are available in various sizes and thicknesses. The most popular range is 2 to 16 inches in diameter, and common thicknesses are from 0.045 in. to 1⁄8 in. Thinner wheels remove less material during the cut.
Some types of wheels cut faster than others. The abrasive material used in the wheel is one influencer on cut rate and consumable life. Wheels come in several grain options, such as aluminum oxide, silicon carbide, zirconia alumina, ceramic alumina, and combinations of these materials.
While not as sharp as other grains, aluminum oxide provides toughness and good performance for cutting on steel. Silicon carbide, on the other hand, is a very sharp grain but not quite as tough, making it suitable for cutting nonferrous metals. Zirconia alumina is a self-sharpening, tough, durable grain that holds up well in a range of demanding applications. Ceramic alumina also is designed to self-sharpen as it “breaks” at predetermined points to maintain a consistent cut rate and long life.
When selecting a resinoid-bonded abrasive wheel, consider that products made with a mixture of zirconia or ceramic alumina with a harder bond typically cost more but offer durability and longer consumable life.
Make sure to refer to the manufacturer’s recommendations, product descriptions, and RPM ratings to select the proper wheel size and bonded abrasive material for your application. Matching the size and RPM rating of the tool to the size and RPM rating of the wheel is critical for safe and effective usage. Choosing the tool with the greatest amperage or amount of torque while staying within size and RPM requirements of the wheel will increase performance.
The kind of tool and the tool guard that you use also are factors that play a role in the type of wheel that can be used for an application. A larger-diameter wheel works best if you’re cutting deep into metal or need to cut a piece with a large diameter, for example, because it eliminates the need to rock the wheel back and forth during the cutting process. Look for a wheel with the diameter designed for the size and thickness of material being cut.
Thin wheels, on the other hand, tend to remove less metal during the cut and have shorter life spans, but provide a quicker cut. There are some exceptions to this as different versions of thin wheels are lasting longer, so be sure to do your research before you make a final decision to ensure the wheel you select maximizes efficiency.
Specialty cutting wheels are also available that are designed for use with certain materials, such as stainless steel and aluminum.
Proper Positioning and Other Tips
In addition to paying attention to designations for RPM rating, size, and material, you should also follow these tips when using resinoid-bonded abrasive cutting wheels.
Use the cutting wheel at a 90-degree angle, perpendicular to the work surface.
Apply the proper amount of pressure—not too much, not too little—to allow the cutting wheel to do the work. Always avoid pushing too hard on the wheel, which can cause the grinder to stall or kick back or give you a much less efficient cutting action. It also increases the chances that you will slip or lose control of the tool, which can cause damage or injury.
Choose a grinder with the highest torque or amperage available for the application, as this will help the wheel to do more of the work. For example, instead of using a 4.5-in. wheel on a 6-amp grinder, use a 4.5-in. wheel on a 10-amp grinder. The RPM rating remains the same, but the tool will provide more torque to cut into the metal.
Choose a tool and consumables that offer quick, consistent cutting, which typically provides the most efficient performance.
Remember, the thinner the cutting wheel, the more susceptible it can be to side loading, which is a term that describes when the wheel bends while moving side to side in the cut. This can turn dangerous if you lean too hard on a wheel, which can cause the wheel to break or jam in the cut. It can also reduce the efficiency of the wheel and increase the cut time.
Store the wheel in a clean, dry environment, and avoid placing it in water or mud. This helps minimize environmental effects that could degrade its performance or cause it to crack or wear prematurely. The performance of resinoid bond tends to deteriorate when the wheel is stored for extended periods of time, so be sure to use FIFO (first in, first out) when using wheels.
Inspect the wheel and consumable before each use to check for signs of damage or wear. Cutting wheels can become harder to control as they wear down. If you can no longer make a safe cut because the wheel’s diameter is worn so thin, then the best course of action is to replace it.
Hole saw basics
Spade bits are the tool of choice for drilling holes up to about 1-1/4 in. in diameter for running electrical wiring and other uses. But when it comes to drilling really big holes for locksets or plumbing pipes, reach for a HSS hole saw. A hole saw is a steel cylinder with saw teeth cut into the top edge. Hole saws don’t cut as quickly as large boring bits driven by a pro’s powerful 1/2-in. drill. But boring bits are expensive ($30 plus drill rental). Hole saws, on the other hand, are readily available at hardware stores and home centers for as little as $5 and work with a standard 3/8-in. drill. Cutting clean holes with hole saws requires a little skill and practice. Here are the key techniques that will make the task safer and give you the best results.
Proper setup is important Mount the correct-size hole saw in the arbor. If your concrete hole saw has an adjustable center bit, make sure it protrudes past the toothed edge of the saw about 3/8 in. (Photo 2). If the center bit has a flat spot on its shank, align this with the setscrew. Then tighten the setscrew to secure the bit. Finally, tighten the holesaw in the chuck of a corded 3/8-in. variable speed drill. Cordless drills won’t have enough power unless they’re 18 volts or larger.
Start slowly and hold on tight Photos 1 – 4 show how to drill a hole in a wood door for a lock or door handle, but the same techniques apply for drilling other holes. When you need a clean, splinter-free hole, drill in from both sides (Photos 1 and 4). The key to getting a perfectly straight hole is to ensure even contact at the start. That will put your drill at a right angle to the door (Photo 3).
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nervousangeltyphoon · 3 years
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Brick Pavers Review: Pros and Cons
Clay brick has been a standard building material for thousands of years, used both for building walls and as paving surfaces for roads, pathways, and courtyards. There is nothing more elegant than a driveway, walkway, or patio paved with brick. Although concrete pavers are somewhat harder and more durable than clay brick, classic brick can still easily stand up to normal driveway usage, provided they are laid over a good base and maintained regularly. And clay brick is arguably the most elegant of all paving surfaces and one that always adds value to your home.
Brick pavers are a manufactured product made of clay that is cast in forms, then heat cured, usually in the shape of a rectangle. Cobblestones, on the other hand, are a natural stone cut into paver shapes; concrete pavers are cast grey bricks made of Portland cement and aggregate.
In contrast to clay brick used for wall construction, paver bricks are solid, smooth-surfaced clay without holes or gaps. Most paver brick is clay-colored and rectangular. Depending on your choice, you can create a driveway, patio, or walkway that looks like it's been around for 100 years or one that fits right in with modern house and landscape designs. Should you someday wish to replace the surface, there is a good market for recycled brick pavers.
Brick Paver Cost
You should be able to buy the materials needed for a brick paver driveway for about $5 per square foot. If you do the job yourself, the labor will be free. Professional installation will probably start at about $10 to $20 per square foot, although fancier designs and pricier bricks can drive that price higher. This makes brick pavers a fairly expensive paving material when compared to poured concrete ($6 to $10 per square foot). Clay brick pavers are also slightly more expensive than concrete pavers.
Maintenance and Repair
Clay pavers will gradually weather over time under the influence of moisture and ultraviolet rays from the sun. Proper maintenance can greatly extend the life of your driveway to 25 years or more.
A glass brick paver driveway should be washed once or twice a year with a pressure washer. Make sure to remove weeds and dirt from between bricks. After the surface dries for a day or two, pack the joints with fresh sand if it is a loose-fit surface. If the pavers are mortared, repair any cracks with fresh mortar and let dry fully.
To ensure a long life, the bricks should be sealed after each washing. If left unsealed, clay brick can begin to flake and peel over time. A sealer can be applied with a good pump sprayer or can be rolled or brushed over the surface. Seal the sand joints as well as the surface of the brick, as this will help solidify the sand and prevent weeds and moss from appearing in the joints.
When sealing a paver driveway, use a product designed for clay brick, such as a siloxane-based sealer, which will protect without changing the appearance of the brick. Avoid gloss-finish sealers, which often result in a splotchy surface. There are, however, "wet look" sealers that look shiny without actually producing a gloss.
Design
Brick pavers make for a very attractive classic paving surface that can work well with almost any home style. Permeable bricks paving is a far more attractive paving surface than poured concrete, but when compared to concrete pavers, the design options are more limited. Brick pavers can be arranged in different patterns, but the sizes are all rectangular, and colors are limited to browns and reds. Concrete pavers, on the other hand, come in a wide variety of shapes and sizes, giving you more flexibility.
Brick Paver Installation
Brick pavers can be set in a base of either paver sand or mortar. As with any driveway material, the key to a good brick paver surface is a well-prepared base—especially when paving a driveway that must support a lot of weight. Outline the area you intend to pave using layout strings, then remove the soil (or the existing paving) to a depth of at least 12 inches. Add 8 to 12 inches of gravel to the excavated area, compacting the gravel periodically as you add layers. Compacting the gravel again after each 2 to 4 inch layer is added. Then add a 1 1/2-inch layer of sand and level it. When the base is ready, start laying bricks in whatever pattern you like.
Installation usually begins with the perimeter bricks, which are sometimes set in concrete to establish a solid edging that will hold the field bricks in place. As the field hollow bricks are installed, they are periodically flattened and "set" by pounding with a mallet. Bricks can be cut individually, but it can be much quicker to trim the edges all at once with a handheld circular saw or rented wet saw fitted with a diamond blade.
Upon completion, the wall brick surface is flattened and leveled with a heavy roller, then the cracks between bricks are filled with loose sand or mortar. Sand-setting is an increasingly preferred method for environmental reasons since it allows rainwater to seep through into the ground.
What Are Roof Tiles?
Roof tiles are primarily made to keep water out of a home. However, they differ from traditional asphalt shingle roofs in both their material composition as well as their looks. As far back as the 1600’s, slate tile roofs were being used, and clay roofs can be traced back as far as 10,000 BC! Slate and clay were popular because they were locally available materials but as we moved into the 19th century, concrete and metal tiles started to appear on a regular basis.
Why are Roof Tiles Preferred Over Shingle Roofs?
A shingle roof keeps the water out, and adds color to your home, including bathroom tiles, kitchen tiles, etc., but roof tiles provide an unmatched variety of options that are simply not available with asphalt shingles.
9 Types of Roof Tiles
Roof tiles are a great way to customize a home, but they vary in budget, durability, weight, and appearance. We break down the 9 most popular types of roof tiles below so that you can get a clear understanding of what sets each material apart.
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nervousangeltyphoon · 3 years
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The Basics of Cutting and Grinding discs
Abrasive-cutting processes are widely used to obtain semi-finished products from metal bars, slabs, or tubes. Thus, the abrasive cutting-off process is applied when requiring precision cutting and productivity at a moderate price. Cut-off tools are discs composed of small abrasive particles embedded in a bonding material, called the binder. This work aims to compare the cutting performance of cutting discs with different composition, in dry cutting of steel bars. To do that, disc wear was measured and disc final topography was digitalized in order to determine both disc surface wear patterns and if the abrasive particles bonding into the binder matrix was affected. In addition, X-Ray inspection gave information about the abrasive grit-binder bonding. Therefore, the method here presented allows identifying discs with a superior abrasive-cutting capability, by combining profilometry and tomography to define micrometrical aspects, grit size, and binder matrix structure. Results led to the conclusion that discs with high grit size and protrusion, high grit retention by bond material, and closer mesh of fiberglass matrix binder were the optimal solution.
Plenty of manual cutting applications call for a hand-held grinder and cutting wheel. Cutting sheet metal, sizing a piece for fabrication, cutting out a weld to refabricate it, and cutting and notching in pipeline work are just a few examples of what can be accomplished using a grinder and cutting wheel.
Resinoid-bonded cutting wheels are a popular choice to achieve these types of cuts because they offer portability and allow you to cut in many different angles and orientations. The bonding agent, in this case resinoid, holds the wheel together so it can cut effectively. The bond wears away as the abrasive grains wear and are expelled so new sharp grains are exposed.
By following a few best practices, you can extend wheel life, promote safety, and improve productivity and efficiency within the process.
The Basics of Cutting Wheels
The main considerations in using resinoid-bonded wheels include the cutting application, the tool being used—such as a right-angle grinder, die grinder, or chop saw—desired cutting action, the material being cut, and space. Wheels typically provide a fast cutting action, long life, and tend to be cost-effective.
The two main types of resinoid-bonded abrasive cutting wheels are Type 1, which are flat, and Type 27, which have a raised hub. Type 1 wheels generally are used for straight-on cutting on electric or pneumatic right-angle grinders or die grinders and chop saws, among other tools. Type 27 wheels are required when there is some type of interference and the metal cutting disc needs to be raised up from the base of the grinder, but personal preference also plays a role in the decision. They are most commonly used with electric or pneumatic right-angle grinders.
Resinoid-bonded abrasive cutting wheels are available in various sizes and thicknesses. The most popular range is 2 to 16 inches in diameter, and common thicknesses are from 0.045 in. to 1⁄8 in. Thinner wheels remove less material during the cut.
Some types of wheels cut faster than others. The abrasive material used in the wheel is one influencer on cut rate and consumable life. Wheels come in several grain options, such as aluminum oxide, silicon carbide, zirconia alumina, ceramic alumina, and combinations of these materials.
While not as sharp as other grains, aluminum oxide provides toughness and good performance for cutting on steel. Silicon carbide, on the other hand, is a very sharp grain but not quite as tough, making it suitable for cutting nonferrous metals. Zirconia alumina is a self-sharpening, tough, durable grain that holds up well in a range of demanding applications. Ceramic alumina also is designed to self-sharpen as it “breaks” at predetermined points to maintain a consistent cut rate and long life.
When selecting a resinoid-bonded abrasive wheel, consider that products made with a mixture of zirconia or ceramic alumina with a harder bond typically cost more but offer durability and longer consumable life.
Make sure to refer to the manufacturer’s recommendations, product descriptions, and RPM ratings to select the proper wheel size and bonded abrasive material for your application. Matching the size and RPM rating of the tool to the size and RPM rating of the wheel is critical for safe and effective usage. Choosing the tool with the greatest amperage or amount of torque while staying within size and RPM requirements of the wheel will increase performance.
The kind of tool and the tool guard that you use also are factors that play a role in the type of wheel that can be used for an application. A larger-diameter wheel works best if you’re cutting deep into metal or need to cut a piece with a large diameter, for example, because it eliminates the need to rock the wheel back and forth during the cutting process. Look for a wheel with the diameter designed for the size and thickness of material being cut.
Thin wheels, such as aluminum cutting disc, on the other hand, tend to remove less metal during the cut and have shorter life spans, but provide a quicker cut. There are some exceptions to this as different versions of thin wheels are lasting longer, so be sure to do your research before you make a final decision to ensure the wheel you select maximizes efficiency.
Specialty cutting wheels are also available that are designed for use with certain materials, such as stainless steel and aluminum.
Proper Positioning and Other Tips
In addition to paying attention to designations for RPM rating, size, and material, you should also follow these tips when using resinoid-bonded abrasive cutting wheels.
Use the cutting wheel at a 90-degree angle, perpendicular to the work surface.
Apply the proper amount of pressure—not too much, not too little—to allow the cutting wheel to do the work. Always avoid pushing too hard on the wheel, which can cause the grinder to stall or kick back or give you a much less efficient cutting action. It also increases the chances that you will slip or lose control of the tool, which can cause damage or injury.
Choose a grinder with the highest torque or amperage available for the application, as this will help the wheel to do more of the work. For example, instead of using a 4.5-in. Grinder cutting wheel on a 6-amp grinder, use a 4.5-in. wheel on a 10-amp grinder. The RPM rating remains the same, but the tool will provide more torque to cut into the metal.
Choose a tool and consumables that offer quick, consistent cutting, which typically provides the most efficient performance.
Remember, the thinner the cutting wheel, the more susceptible it can be to side loading, which is a term that describes when the wheel bends while moving side to side in the cut. This can turn dangerous if you lean too hard on a wheel, which can cause the wheel to break or jam in the cut. It can also reduce the efficiency of the wheel and increase the cut time.
Store the wheel in a clean, dry environment, and avoid placing it in water or mud. This helps minimize environmental effects that could degrade its performance or cause it to crack or wear prematurely. The performance of resinoid bond tends to deteriorate when the wheel is stored for extended periods of time, so be sure to use FIFO (first in, first out) when using wheels.
Inspect the wheel and consumable before each use to check for signs of damage or wear. Cutting wheels, including angle grinder cutting discs can become harder to control as they wear down. If you can no longer make a safe cut because the wheel’s diameter is worn so thin, then the best course of action is to replace it.
A grinding disc is defined by the type of abrasive material, bonding material, grain size, structure of the wheel, and grade of the wheel used for the machining of a component. These factors decide the grinding efficiency of the grinding wheel and surface finish quality of the machined component. A wide range of abrasives are being used in modern era to overcome necessities in machining of various make of components. Abrasives ranging from the economic verses of aluminium oxide to the likes of super-abrasives such as cubic boron nitride and the expensive diamond grains are used for machining as well as surfacing purposes. Over the years, research has depicted that no distinct abrasive material can meet all the requirements of grinding applications. The mechanical and physical properties of a particular abrasive material make it suitable for a certain application.
Wire Brushes
A wheel wire brush is an abrasive tool that has stiff bristles made from a variety of rigid materials designed to clean and prepare metal surfaces. The filaments of wire brushes are small diameter pieces of inflexible material that are closely spaced together as a means for cleaning surfaces that require aggressive and abrasive tools. The means of applying the brush can be either manual or mechanical depending on the type of brush and the surface to be treated.
The short video below explains the manufacturing of a unique type of wire brush called a wire drawn brush, which is a very sturdy and durable brush that is made by a process that ensures filament retention.
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nervousangeltyphoon · 3 years
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Watches for kids
It often seems that analog wristwatches have gone the way of the landline, the film camera, and the crowded indoor restaurant. And while you may be resigned to telling time with your phone, there’s still a chance for your kid to get a kick out of an old-school analog watch. Kids watches are not only a very cool accessory (and one with a low risk of getting lost, since they’re tethered to their hands), but the best kids watches help children understand the progression of their day in hours and minutes, and help them learn the fundamentals of telling time in a much more direct way than a  smartphone or digital clock.
Kids start grasping the concept of time (though it remains somewhat abstract) around the first grade, and time becomes continually integrated into their daily lives. To help them make the connection, look for a kids watch with a face that’s big, bright, and easy to read. A band that’s cool and on-trend doesn’t hurt either.
So the next time you tell your kid they have six minutes until their Zoom class starts, they’ll know that you’re talking about something concrete, instead of some ephemeral concept, and you won’t have to nag to get things running on schedule. Just kidding: You’ll still have to nag.
CONNECTING EVERY POSSIBLE device in our lives to the internet has always represented a security risk. But that risk is far more pronounced when it involves a smartwatch strapped to your child's wrist. Now, even after years of warnings about the security failings of many of those devices, one group of researchers has shown that several remain appallingly easy for hackers to abuse.
In a paper published late last month, researchers at the Münster University of Applied Sciences in Germany detailed their testing of the security of six brands of smartwatches marketed for kids. They're designed to send and receive voice and text messages, and let parents track their child's location from a smartphone app. The researchers found that hackers could abuse those features to track a target child's location using the watch's GPS in five out of the six brands of watch they tested. Several of the watches had even more severe vulnerabilities, allowing hackers to send voice and text messages to children that appear to come from their parents, to intercept communications between parents and children, and even to record audio from a child's surroundings and eavesdrop on them. The Münster researchers shared their findings with the smartwatch companies in April, but say that several of the bugs they disclosed have yet to be fixed.
When we get asked to buy kids watch or we just want to buy their first proper watch we really don’t know what to buy, a compass? or a just a PVC pencil case. This is where we come in. A kids watch is much more than a simple gift. Our gift is most often kept as a keep safe and treasured for many years. Most children get their first watch between the ages of 8 and 10 when they are still growing in terms of character and personality but start to assimilate things around them that will later on mark their personalities and behavior. Children at this age start to want to choose their own clothes, style their own hair and choosing the perfect kids watch is an element that plays along with these types of needs and habits. On many occasions it is their first real watch, a watch set for kids is an accessory that is much more than an object that simply tells the time.
Viceroy watches is a brand that is characterized in popularity for offering a wide range of kids watches online. The brand knows how to satisfy the customer in terms of characteristics and the fact that the prices of these ones are more than affordable.
Before we go in to more details it is necessary to know a few things about the watch:
That it is practical and easy to use. We mustn’t forget that these are children and not adults.
It is water resistant.. At this age they want to wear their watch in summer and in places where it will most definitely get wet.Once we have this established we can choose our model, taking into account the following things:
Kids Watches depending some factors:
Boy or Girl.
Is our gift for a boy or girl?
Build.
Nowadays, watch manufacturers personalize kids watches depending on their height, wrist size etc.
Taste.
Tastes amongst kids at this age tend to be varied to say the least. There are many to choose from nowadays, sporty, more grown-up, football/soccer teams, cartoon kids watch…
Price.
The fact that nowadays people are pulling in their belts as far as price is concerned is no problem whatsoever. We can buy great kids watches, like a quartz watch at affordable prices. Price is not what matters anyway. However, Viceroy also has more expensive kids watches if we want to spend more.
So, let’s go over the different options we have when it comes to buying watches for kids. A great choose would be the Viceroy 432256-04, with an analogue quartz movement fitted with a white leather strap and crystals decorating the dial. A classic style that will sure be loved.
If the gift is for a boy we can choose the Viceroy 432319-54 that has a black dial with black details. Apt for use in the shower and swimming. It is not so much a classic watch but sportier in design given that it is fitted with a stainless steel bracelet strap.
A similar female version would be the Viceroy 40942-05, with a white face and 24mm in diameter. The strap is unique and pretty given that it is made up of butterflies.
If you want and can spend a little bit more a good option is this Viceroy 432311-35, a multi-function with a stainless steel strap. It is an analogue model and water resistant for use in the shower and swimming pool. The dial is an elegant blue that goes well with almost everything. A model that is both modern and classic. A great gift for any child. It costs about 100 euros. The brand also offers multifunction and chronograph watches for kids, boys and girls alike.
Sporty watches for kids.
Lastly, we would like to fill you in on other kids watches available from the brand. If the boy or girl, you are buying the watch for is a football/soccer fan then we stock several different models of Real Madrid Watches Each one featuring the club’s shield and comes in different colors that represent the different strips. If we look closely at the collection you will find many possibilities that are great options.
This brand offers some fantastic kids watches, including LED kids watch, that are great as gifts. We can choose watches for kids that suit our tastes and price range amongst other things. A child’s first proper watch is a gift for life, something that they will treasure for many years to come. An unforgettable gift and this it what makes it special.
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nervousangeltyphoon · 3 years
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Best Rolling TV Cart and TV mount – High-quality, cutting-edge products
Mounting a TV is a great way to free up space in your living room. If you’ve got kids who get touchy with electronics that they shouldn’t be putting their hands on, an out-of-reach TV will keep gooey prints off your new OLED screen. In terms of visual charm, mounting a TV is a staple of modern home decor. It’s aesthetically pleasing, especially with TVs getting thinner every year. Plus, they can go anywhere from a flat wall to a corner, and even above a fireplace (although we advise exercising caution when doing so).
If you’re on the fence about mounting your new set, where it should go, and what mount you need, we’ve put together this guide on what to consider about your home before mounting, and what hardware you should be on the lookout for to get the job done right.
What’s with your walls?
Almost all universal TV mount are compatible with drywall and come with all the necessary hardware you need to install, including bolts and drywall anchors. If you are installing your wall mount on a plaster or masonry surface, you’ll need some stronger hardware that won’t come in the wall mount box. (Not sure what type of material your walls have? ) This may require a trip to the local home or hardware store to gather the necessary power tools and products. One other thought about location: We suggest you avoid mounting a TV over a fireplace if you can — check out this article for our thoughts on that controversial topic.
Just as most TV wall mounts are compatible with drywall, all TVs use a standard mounting pattern, called a VESA pattern. The name is an acronym for the Video Electronics Standards Association, the body that decided what that generic pattern is. Basically, it just means that whichever wall mount you choose, it will be easy to attach to your TV.
Size, weight, and flexibility
When looking at wall mounts online, they will most likely be rated by the screen size of the TV they support and the weight they can hold, the latter of which is the most important factor. Different brands vary in weight even if the sizes of TVs are the same. If you are looking at a TV wall mount online, check the product description to see more information about the maximum weight and screen size it can handle. You can also find this info on the wall mount’s box.
The next thing to consider is the flexibility you want your TV to have while mounted. If you want to be able to see your TV from other rooms, a good option is a pivoting wall mount. This will let you change the direction the TV is facing to optimize the picture on the screen, even if you aren’t sitting right in front of the TV. If you are mounting your TV above the average eye level (42 inches), you’ll want to invest in a TV wall mount that tilts down to improve picture quality, thus for tilt TV mount. Fortunately, most mounts can tilt and pivot.
If the TV can be positioned at the ideal height and you don’t need to access the TV ports on a regular basis, a fixed TV wall mount will simplify the installation and the TV will be close to the wall, taking up less space. Consider a slim mount if this is the case for a more elegant overall appearance. Many tout how close they can hang to the wall.
If you are mounting your TV in the corner, you will most likely need a specially designed corner mount. A fully articulating mount is necessary to secure the mounting plate to the wall and keep the TV extended at all times.
One final consideration is a universal TV base. Combining the best of both worlds (table-top and wall mounting), these universal bases come with VESA-certified mounting arms and a bracket to hang them from. The bracket itself is normally height-adjustable, and many models will even allow you to tilt and swivel your TV from side to side.
To sum up, when selecting your TV wall mount, make sure you keep in mind the mount style you will need and pay special attention to the amount of weight the mount can hold. If you need help installing your new full motion TV mount, check out our how-to guide to mounting a TV. Once you have the wall mount installed and the TV hooked up, all you need to do is sit back, relax, and enjoy your favorite show or movie.
This is a big advantage over the fixed and tilting models which require a large flat wall area – and also require you to view the TV straight-on. With this type of mount, you can push it against the wall when not in use, but then pull it out and angle it towards the room when viewing. As I said earlier, the term articulating wall mount does cover a wide variety of mounts. The most flexible type of mounts are full motion TV mounts. Also called fully articulating, or cantilever TV mounts, these TV wall mounts are the most versatile type that you can buy. They will allow you to move the screen to almost any position you could possibly want.
Rolling TV stands, or TV cart, or mobile TV cart, are a great video and graphic solution for businesses. They help boost your presentations in conference rooms, trade shows, hotels, meetings, and other settings.
Because they are mobile you can take them in different places without having to worry about dislodging the displays from walls. And since most TV rolling stands are height adjustable and can be tilted, you can adjust them to your viewing preference.
Some TV stands come with shelves for storing items such as laptops, sovund systems and speakers, allowing you to have your presentation on wheels. There is a wide range of rolling TV stands in the market. To help you narrow down the list, here are some of our picks for the best rolling TV stands.
Do you want to buy the best rolling TV stand cart? Are you looking for a flat-screen TV cart with wheels? In this article, we will help you choose the best rolling TV stand or cart. Many people don’t like hanging up their TVs on the wall like a frame.
If you are among them, you need a rolling TV cart that allows you to move your TV anywhere in your home. Not only it protects the TV from damages, but a rolling TV cart is also compact and lightweight.
In this article, we have a list of the best rolling TV carts as well as buying criteria that enable you to choose the best product to meet your specific needs. Without further ado, let’s review the rolling TV carts.
ONKRON TV stand or rolling cart is designed for TV sizes of 55 inches to 80 inches. It is an ideal product for curved panel screens, OLED plasma flat, LCD, and LED TVs with VESA mounting holes supporting from a minimum 200x200mm to maximum 800x500mm.
It is made of high-quality steel material that ensures the security of your TV and stable fixation. It can bear a TV weight of up to 200 pounds. It comes with a detailed instructional manual, which helps in quick and easy assembly. The essential hardware accessories make it easy for you to install your TV on the cart.
Perlesmith Mobile TV stand is a flat-screen TV cart with wheels and swivel wall mount TV bracket designed for accommodating 23 inches to 55 inch LED, LCD, and curved and flat screens. It can handle a weight of 55 pounds. It is a rolling TV cart that fits VESA from 100x100mm to 400x400mm.
The interesting feature of Perlesmith mobile TV stand is its adjustable tray that has a strong media shelf holding your DVD player, laptop, or gaming console. The distance from the AV shelf to the floor is 12 inches to 24 inches. You can adjust the wall mount plate and choose your preferred height. This allows for a customizable viewing experience.
Perlesmith mobile TV stand comes with a built-in wire management system in its metal column, which allows for simple organization and concealment of cables and wires in the back of the stand.
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nervousangeltyphoon · 3 years
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Adding efficiency to general lab equipment
General equipment makes up a lab’s foundation. Without these crucial tools, few experiments could be performed, because nearly every research project depends on one or more of such technologies. As fundamental elements of research, general lab equipment must also be efficient. “Energy efficiency in laboratory equipment is extremely important,” says John Dilliott, energy manager at the University of California, San Diego. “It’s a major, yet virtually untapped area.” He mentions that My Green Lab, a California-based nonprofit, published a 2015 report estimating that there are more than 1.2 billion square feet of laboratory space in the United States. “These spaces are three to five times more energy intensive than office areas due to energy-intensive equipment, around-the-clock operations, 100 percent outside-air requirements, and high airflow rates,” Dilliott says. “Not only does laboratory equipment consume a substantial amount of energy, but anyone who has ever been in a lab knows that the heat generated by lab equipment can lead to overcompensation by heating, ventilation, and air-conditioning systems, resulting in an additional increase in energy consumption.”
By saving energy, it takes less capital to run a piece of equipment, and some of the most basic equipment consumes a lot of electricity. According to the website of the International Institute for Sustainable Laboratories (I2SL) in Arlington, Virginia: “The energy used by [plug-in] equipment (e.g., freezers, autoclaves, centrifuges) constitutes from 10 to as much as 50 percent of the total energy use in a laboratory (not including associated cooling energy use).” I2SL’s web page adds, “Many scientists, laboratory managers, and laboratory design consultants are beginning to use energy efficiency as a selection criterion for laboratory equipment, such as laboratory oven, and some manufacturers are starting to advertise the ‘green features’ of their products.” In an effort to start a central database of energy-efficiency information, I2SL created the Energy-Efficient Laboratory Equipment Wiki (http://scim.ag/EELEWiki).
When considering any technology upgrade for energy efficiency, scientists wonder about the payback: How long will it take to recoup the price of the new equipment through energy savings? “Payback is a difficult question to answer as it’s dependent on the initial purchase price, the cost of energy, how the equipment is used, and the type of equipment that is being replaced,” says Allison Paradise, executive director of My Green Lab. “In addition, so few studies have been done on energy consumption of laboratory equipment that it’s often difficult to know, without metering, what the baseline energy consumption is of the existing equipment and what the energy consumption is of the new equipment.” She adds, “Our nonprofit cofounded the Center for Energy Efficient Laboratories (CEEL) to address this specific need”—gathering real-world data on the energy used by general lab equipment. Only with those data in hand can scientists choose the most efficient devices.
An incubator comprises a transparent chamber and the equipment that regulates its temperature, humidity, and ventilation. For years, the principle uses for the controlled environment provided by incubators included hatching poultry eggs and caring for premature or sick infants, but a new and important application has recently emerged, namely, the cultivation and manipulation of microorganisms for medical treatment and research. This article will focus on laboratory (medical) incubators.
A laboratory magnetic stirrer is a device widely used in laboratories and consists of a rotating magnet or a stationary electromagnet that creates a rotating magnetic field. This device is used to make a stir bar, immerse in a liquid, quickly spin, or stirring or mixing a solution, for example.
Laboratory shakers are a key piece of equipment in any biological laboratory. Their versatility enables scientists to easily culture, monitor and scale up a range of experiments including biofuel research and microbiological cultures. When buying a new biological shaker, it’s important to consider the experiments and applications you want to use it for and the people using it. The following guide highlights seven key matters to consider when choosing the right shaker for your laboratory.
1) Orbit size
The diameter of the orbit of your shaker is an important factor when considering different shakers; different orbit sizes suit different culturing techniques and applications.
Aeration and circulation of the growth medium in your experiment is directly affected by the orbit size, so maximise your culturing efficiency by choosing the best orbit size for your application.
Most shakers are available in a 2.5cm and 5.1cm orbit. In general, a 2.5 cm orbit is a standard option for most applications, but higher volume experiments e.g. >2 litres, or shear sensitive cells may benefit from a larger diameter orbit.
2) Shaking
Oxygenation of the cultures also depends on the speed of the agitation. By increasing the agitation speed, the surface area of the liquid increases by washing against the side of the flask, enabling better aeration of the culture if done at an optimal speed.
3) Temperature control
Biological culturing is a precise and temperamental process; sudden changes in temperature can massively affect your culture and so incorporating good temperature control is an important factor to consider in instrument selection.
Reproducibility and consistency are crucial when culturing, so it’s also important to consider the uniformity of any heating/cooling across the whole of your shaker.
A laboratory muffle furnace is a critical component for high-temperature laboratory heating, enabling samples to be heat-treated at temperatures exceeding 1000°C (1832°F) with low risk of cross-contamination.
Rotary evaporator packages have been around for quite some time now, having been developed over 50 years ago to deal with problems faced with standard chemical distillation devices. Those issues included annihilation of the substances being distilled and slow boiling. Rotary evaporators prevent such problems through the spinning motion of the vessel, which speeds distillation by increasing the surface area of the liquid. This type of evaporator also provides a gentler, higher quality distillation process than standard procedures, according to a white paper from IKA. All basic rotary evaporators are made up of a vacuum source, collection flask, rotating flask, temperature bath and condenser. While oil may be used for the bath in order to reach temperatures of 180 C, water is the most commonly used substance. If you’re looking for a rotary evaporator, it’s important to think about whether or not you need automated options and what cooling option is best for you. Vacuum control is also crucial as vacuum that is achieved too quickly can cause foaming and bumping. As always, consulting your vendor can help you make the right choice of rotary evaporator for your lab.
The growth of Life science products has created geographic concentrations of interconnected life sciences companies and institutions, or “clusters,” forming in key global locations, including in the U.S. and the UK. The forming of clusters has been driven by a variety of factors, including a broad recognition that proximity between market participants can drive overall productivity. While it may seem paradoxical for a company to locate near its competitor, a deeper examination reveals that clustering creates synergies for all participants who can benefit from communal resources, regional trade, lobby and support groups, shared infrastructure and logistics channels, and a common regulatory and legal framework (and, in some instances, local tax incentives).
Traditionally, life sciences clusters have organically developed over time near recognized research universities and teaching hospitals, as these provide ready access to talent across key scientific disciplines and easy means for intellectual property transfer from these institutions to private companies. In recent times, traditional big spenders on R&D in the life sciences sector (like big pharma) have increasingly favoured collaboration, often with smaller venture-funded companies that have spun out from leading academic institutions, as a means of achieving a stake in innovation while reducing in-house R&D risk and expenditure. An interesting by-product of the growth of venture-funded companies is the increasing availability of flexible short-lease lab spaces targeted at covenant weak start-ups and SMEs.
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