hydraulics-en-blog

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Mineral oil

For crude oil found in geological deposits, see Petroleum. Bottle of mineral oil as sold in the U.S. A mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum. The name mineral oil by itself is imprecise, having been used for many specific oils over the past few centuries. Other names, similarly imprecise, include white oil, liquid paraffin, pariffinum liquidum (Latin), and liquid petroleum. Baby oil is a perfumed mineral oil. Most often, mineral oil is a liquid by-product of refining crude oil to make gasoline and other petroleum products. This type of mineral oil is a transparent, colorless oil composed mainly of alkanes and cycloalkanes, related to petroleum jelly. It has a density of around 0.8 g/cm3. Mineral oil is a substance of relatively low value, and it is produced in very large quantities. Mineral oil is available in light and heavy grades, and can often be found in drug stores. Three basic classes of mineral oils exist: Alkanes, based on n-alkanes Naphthenic oils, based on cycloalkanes Aromatic oils, based on aromatic hydrocarbons (distinct from essential oils) ^ Mineral oil (Dictionary.com) ^ , efsa.europa.eu[dead link] ^ "Mechanical properties of materials". Kaye and Laby Tables of Physical and Chemical Constants. National Physical Laboratory. Retrieved 2008-03-06.  More details Android, Windows

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Manometer

Redirect to: Pressure measurement#Liquid column (manometer) More details Android, Windows

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Radial shaft seal

Radial shaft seal of Romo washing machine pump Radial shaft seals, also known as lip seals, are used to seal rotary elements, such as a shaft or rotating bore. Common examples include strut seals, hydraulic pump seals, axle seals, power steering seals, and valve stem seals. Early radial shaft seals utilized rawhide as the sealing element, and many elastomeric seal companies today once were tanneries. The advent of modern elastomers replaced rawhide, industry also added a garter spring which helps the sealing lip compensate for lip wear and elastomer material changes. The seal construction will consist of a sprung main sealing lip which has a point contact with the shaft. The point contact is formed by two angles, with the air side angle usually less than the oil side angle. Depending on the seal type these two angles are varied to create a pressure distribution at the seal contact point which has a steeper slope on the oil side of the seal. The shallower the slope on the oil side of the seal the wetter the seal will run. The spring is positioned such that axially the centerline of the spring is biased to the air side of the lip contact point. In order to exclude contaminants numerous types of dust lips or exclusionary lips may be used. Common elastomers include FKM, ACM, NBR, HNBR, and AEM. In order to resist wear, the compounds' durometer (hardness) is typically 70 to 85 Shore A (between that of an automobile tire and a soft inline-skate wheel). A different seal design for similar applications is a rotating face seal. More details Android, Windows

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Slide valve

Cylinder, with slide valve removed to show ports A double-acting slide valve cylinder. Steam enters via the steam port SP, and is admitted by the slide valve SV  through the upper passage S  to push down the piston P. At the same time, exhaust steam from below the piston passes back up the lower passage S, via the valve cavity, to exhaust E. As the piston descends, the valve moves upwards to admit steam below the piston and release exhaust from above. The slide valve is a rectilinear valve used to control the admission of steam into, and emission of exhaust from, the cylinder of a steam engine. The image description page explains how this SVG animation can be viewed More details Android, Windows

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Piston valve

For valves used in modern combustion engines (piston within cylinder), see Poppet valve § Internal combustion engine. For piston valves on steam locomotives, see Piston valve (steam engine). Piston valve in a brass instrument A piston valve is a device used to control the motion of a fluid along a tube or pipe by means of the linear motion of a piston within a chamber or cylinder. Examples of piston valves are: The valves used in many brass instruments The valves used in pneumatic cannons The valves used in many stationary steam engines and steam locomotives More details Android, Windows

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Hydraulic cylinder

The hydraulic cylinders on this excavator operate the machine's linkages. A hydraulic cylinder (also called a linear hydraulic motor) is a mechanical actuator that is used to give a unidirectional force through a unidirectional stroke. It has many applications, notably in construction equipment (engineering vehicles), manufacturing machinery, and civil engineering. More details Android, Windows

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Hydraulic motor

A small hydraulic motor A hydraulic motor is a mechanical actuator that converts hydraulic pressure and flow into torque and angular displacement (rotation). The hydraulic motor is the rotary counterpart of the hydraulic cylinder. Conceptually, a hydraulic motor should be interchangeable with a hydraulic pump because it performs the opposite function - similar to the way a DC electric motor is theoretically interchangeable with a DC electrical generator. However, most hydraulic pumps cannot be used as hydraulic motors because they cannot be backdriven. Also, a hydraulic motor is usually designed for working pressure at both sides of the motor. Hydraulic pumps, motors, and cylinders can be combined into hydraulic drive systems. One or more hydraulic pumps, coupled to one or more hydraulic motors, constitute a hydraulic transmission. Swing Bridge, River Tyne One of the first rotary hydraulic motors to be developed was that constructed by William Armstrong for his Swing Bridge over the River Tyne. Two motors were provided, for reliability. Each one was a three-cylinder single-acting oscillating engine. Armstrong developed a wide range of hydraulic motors, linear and rotary, that were used for a wide range of industrial and civil engineering tasks, particularly for docks and moving bridges. The first simple fixed-stroke hydraulic motors had the disadvantage that they used the same volume of water whatever the load and so were wasteful at part-power. Unlike steam engines, as water is incompressible, they could not be throttled or their valve cut-off controlled. To overcome this, motors with variable stroke were developed. Adjusting the stroke, rather than controlling admission valves, now controlled the engine power and water consumption. One of the first of these was Arthur Rigg's patent engine of 1886. This used a double eccentric mechanism, as used on variable stroke power presses, to control the stroke length of a three cylinder radial engine. Later, the swashplate engine with an adjustable swashplate angle would become a popular way to make variable stroke hydraulic motors. More details Android, Windows

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Hydraulic accumulator

A hydraulic accumulator is a pressure storage reservoir in which a non-compressible hydraulic fluid is held under pressure that is applied by an external source. The external source can be a spring, a raised weight, or a compressed gas.[note 1] An accumulator enables a hydraulic system to cope with extremes of demand using a less powerful pump, to respond more quickly to a temporary demand, and to smooth out pulsations. It is a type of energy storage device. Compressed gas accumulators, also called hydro-pneumatic accumulators, are by far the most common type. More details Android, Windows

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Directional control valve

Directional control valves are one of the most fundamental parts in hydraulic machinery as well as pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled. The movement of the spool restricts or permits the flow, thus it controls the fluid flow. More details Android, Windows

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Breaker

A breaker is mounted on the excavator on the left side A breaker is a powerful percussion hammer fitted to an excavator for demolishing concrete structures or rocks. It is powered by an auxiliary hydraulic system from the excavator, which is fitted with a foot-operated valve for this purpose. Additionally, demolition crews employ the hoe ram for jobs too large for jackhammering or areas where blasting is not possible due to safety or environmental issues. Breakers are often referred to as "hammers", "peckers", "hoe rams" or "hoe rammers." These terms are popular and commonly used amongst construction/demolition workers. The first[citation needed] hydraulic breaker "Hydraulikhammer HM 400" was invented in 1967 by German company Krupp (today German company Atlas Copco) in Essen.[citation needed] More details Android, Windows

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Variable displacement pump

A variable displacement pump is a device that converts mechanical energy to hydraulic (fluid) energy. The displacement, or amount of fluid pumped per revolution of the pump's input shaft can be varied while the pump is running. Many variable displacement pumps are "reversible", meaning that they can act as a hydraulic motor and convert fluid energy into mechanical energy. More details Android, Windows

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Hydraulic machinery

This article is about power machinery. For civil engineering concerning water management, see Hydraulics. "Hydraulic equipment" redirects here. For exercise equipment using hydraulic cylinders for resistance, see Resistance training. An excavator; main hydraulics: Boom cylinders, swingdrive, cooler fan and trackdrive Fundamental features of using hydraulics compared to mechanics for force and torque increase/decrease in a transmission. Hydraulic machines are machinery and tools that use liquid fluid power to do simple work. Heavy equipment is a common example. In this type of machine, hydraulic fluid is transmitted throughout the machine to various hydraulic motors and hydraulic cylinders and becomes pressurised according to the resistance present. The fluid is controlled directly or automatically by control valves and distributed through hoses and tubes. The popularity of hydraulic machinery is due to the very large amount of power that can be transferred through small tubes and flexible hoses, and the high power density and wide array of actuators that can make use of this power. Hydraulic machinery is operated by the use of hydraulics, where a liquid is the powering medium. More details Android, Windows

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Venturi effect

The pressure in the first measuring tube (1) is higher than at the second (2), and the fluid speed at "1" is lower than at "2", because the cross-sectional area at "1" is greater than at "2". A flow of air through a venturi meter, showing the columns connected in a manometer and partially filled with water. The meter is "read" as a differential pressure head in cm or inches of water. Flow in a Venturi tube The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe. The Venturi effect is named after Giovanni Battista Venturi (1746–1822), an Italian physicist. More details Android, Windows

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Gear pump

An exploded view of an external gear pump. Fluid flow in an external gear pump Water flows from left to right in this internal gear pump. Oil pump from a scooter engine A gear pump uses the meshing of gears to pump fluid by displacement. They are one of the most common types of pumps for hydraulic fluid power applications. Gear pumps are also widely used in chemical installations to pump high viscosity fluids. There are two main variations; external gear pumps which use two external spur gears, and internal gear pumps which use an external and an internal spur gears (internal spur gear teeth face inwards, see below). Gear pumps are positive displacement (or fixed displacement), meaning they pump a constant amount of fluid for each revolution. Some gear pumps are designed to function as either a motor or a pump. More details Android, Windows

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Ball valve

This article is about ball valves. For the float valve used in toilet tanks, see ballcock. Cut-away view of a ball-valve mechanism Cut-away view of ball valve components: 1) body 2) seat 3) floating ball  4)  lever handle  5) stem A ball valve is a form of quarter-turn valve which uses a hollow, perforated and pivoting ball to control flow through it. It is open when the ball's hole is in line with the flow and closed when it is pivoted 90-degrees by the valve handle. The handle lies flat in alignment with the flow when open, and is perpendicular to it when closed, making for easy visual confirmation of the valve's status. Ball valves are durable, performing well after many cycles, and reliable, closing securely even after long periods of disuse. These qualities make them an excellent choice for shutoff and control applications, where they are often preferred to gates and globe valves, but they lack their fine control in throttling applications. The ball valve's ease of operation, repair, and versatility lend it to extensive industrial use, supporting pressures up to 1000 bar and temperatures up to 752 °F (400 °C), depending on design and materials used. Sizes typically range from 0.2 to 48 inches (0.5 cm to 121 cm). Valve bodies are made of metal, plastic, or metal with a ceramic; floating balls are often chrome plated for durability. One disadvantage of a ball valve is that they trap water in the center cavity while in the closed position. In the event of a freeze, the sides can crack due to expansion of ice forming. Some means of insulation or heat tape in this situation will usually prevent damage.Another option for cold climates is the "freeze tolerant ball valve". This style of ball valve incorporates a freeze plug in the side so in the event of a freeze up, the freeze plug ruptures, (acts as a sacrificial disk), thus making for an easy repair. Now instead of replacing the whole valve, just screw in a new freeze plug. In the case that a ball valve is used for cryogenics or product that may expand inside of the ball, there is a vent drilled into the upstream side of the valve. This is referred to as a vented ball. Safety is the number one concern when engineers specify a vented ball. A ball valve should not be confused with a "ball-check valve", a type of check valve that uses a solid ball to prevent undesired backflow. Other types of quarter-turn valves include the butterfly valve and plug valve and freeze proof ball valve. More details Android, Windows

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Centrifugal pump

Warman centrifugal pump in a coal preparation plant application Centrifugal pumps are a sub-class of dynamic axisymmetric work-absorbing turbomachinery. Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The rotational energy typically comes from an engine or electric motor. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), from where it exits. Common uses include water, sewage, petroleum and petrochemical pumping; a centrifugal fan is commonly used to implement a vacuum cleaner. The reverse function of the centrifugal pump is a water turbine converting potential energy of water pressure into mechanical rotational energy. More details Android, Windows

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Chézy formula

In fluid dynamics, the Chézy formula describes the mean flow velocity of steady, turbulent open channel flow: v = C R i , {\displaystyle v=C{\sqrt {R\,i}},\,} where v {\displaystyle v} is the mean velocity [m/s], C {\displaystyle C} is the Chézy coefficient [m½/s], R {\displaystyle R} is the hydraulic radius (~ water depth) [m], and i {\displaystyle i} is the bottom slope [m/m]. The formula is named after Antoine de Chézy, the French hydraulics engineer who devised it in 1775. More details Android, Windows