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Encyclopedia > Valve

Contents

These water valves are operated by handles.
These water valves are operated by handles.

A valve is a device that regulates the flow of substances (either gases, fluidized solids, slurries, or liquids) by opening, closing, or partially obstructing various passageways. Valves are technically pipe fittings, but usually are discussed separately. Image File history File links Broom_icon. ... Image File history File linksMetadata Download high-resolution version (3008x2000, 3024 KB) Summary Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Valve Metadata This file contains additional information, probably added from the digital camera or scanner used... Image File history File linksMetadata Download high-resolution version (3008x2000, 3024 KB) Summary Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Valve Metadata This file contains additional information, probably added from the digital camera or scanner used... For other uses, see Gas (disambiguation). ... For other uses, see Solid (disambiguation). ... For other uses, see Liquid (disambiguation). ... Fittings are used in pipe and plumbing systems to connect straight pipe or tubing sections, to adapt to different sizes or shapes, and to regulate fluid flow, for example. ...


Valves are used in a variety of applications including industrial, military, commercial, residential, transportation. Plumbing valves are the most obvious in everyday life, but many more are used. A plumber wrench for working on pipes and fittings A complex arrangement of rigid steel piping, stop valves regulate flow to various parts of the building. ...


Some valves are driven by pressure only, they are mainly used for safety purposes in steam engines and domestic heating or cooking appliances. Others are used in a controlled way, like in Otto cycle engines driven by a camshaft, where they play a major role in engine cycle control. // The term steam engine may also refer to an entire railroad steam locomotive. ... The word appliance has several different areas of meaning, all usually referring to a device with a narrow function: One class of objects includes items that are custom-fitted to an individual for the purpose of correction of a physical or dental problem, such as prosthetic, orthotic appliances and dental... The four-stroke cycle of an internal combustion engine is the cycle most commonly used for automotive and industrial purposes today ( cars and trucks, generators, etc). ... An engine is something that produces some effect from a given input. ... For the fictional characters of the same name, see Camshaft (Transformers). ...


Application

A large variety of valves are available and have many applications with sizes ranging from small to large. The cost of valves ranges from very cheap simple disposable valves, in some items to very expensive valves for specialized applications. Often not realized by some, small valves are even inside some common household items including liquid or gel mini-pump dispenser spigots, spray devices, some rubber bulbs for pumping air, etc., manual air pumps and some other pumps, and laundry washers. Valves are almost as ubiquitous as electrical switches. Often a valve is part of some object, the valve body and the object made in one piece; for example, a separatory funnel. Faucets, taps, and spigots are all variations of valves. Many fluid systems such as water and natural gas lines in houses and other buildings have valves. Fluid systems in chemical and power plants and other facilities have numerous valves to control fluid flow. Separating funnel. ... Categories: Stub ... Indoor Tap - commonly found in the bathroom/laundry and/or kitchen. ... This article is about the fossil fuel. ... A Chemical plant is an industrial process plant that manufactures chemicals, usually on a large scale. ... A power station (also power plant) is a facility for the generation of electric power. ...


Valve parts

Body

The majority of the valve consists of the valve body, including most of the exterior. The valve body is the vessel or casing that holds the fluid going through inside the valve. Valve bodies are most commonly made of various metals or plastics, although valve bodies fused with glass laboratory items in one piece are also made of glass. Brown glass jars with some clear lab glassware in the background Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories. ...


Ports

The body consists of two or more openings, called ports from which movement occurs from one opening to the next. These ports are controlled by a valve. Valves with two or three ports are the most common, while valves consisting of four or more ports are not as frequently used. Extra ports that are not needed can be closed off by the valve. Manufacturing of valves often occurs with the intent that they will be connected with another specific object. These objects can vary, but generally these include some type of piping, tubing, or pump head. In some cases, a valve port is immediately connected to a spray nozzle or container. To make a connection, valves are commonly measured by the outer diameter the ports they connect to. For example, a 1-inch valve is sized to connect to 1-inch outer diameter tubing. Pipe is a tube or hollow cylinder for the conveyance of fluid. ... Tubing refers to a flexible hose or pipe used in plumbing, irrigation, and other industries. ... This article is about a mechanical device. ...


Combined with a valve, ports have the ability to act as faucets, taps, or spigots, all while one or more of its remaining ports are left unconnected. Most valves are built with some means of connection at the ports. This includes threads, compression fittings, glue or cement application (especially for plastic), flanges, or welding (for metals). A compression fitting 15 mm isolating valve // Compression fittings are used in plumbing to join two tubes or thin-walled pipes together. ... Welding is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. ...


Discs and rotors

Inside the valve body, flow through the valve may be partly or fully blocked by an object called a disc. Although valve discs of some kinds of valves are traditionally disc-shaped, discs can come in various shapes. Although the valve body remains stationary within the fluid system, the disc in the valve is movable so it can control flow. A round type of disc with fluid pathway(s) inside which can be rotated to direct flow between certain ports can be called a rotor. Ball valves are valves which use spherical rotors, except for the interior fluid passageways. Plug valves use cylindrically-shaped or conically-tapered rotors called plugs. Other round shapes for rotors are possible too in rotor valves, as long as the rotor can be turned inside the valve body. However not all round or spherical discs are rotors; for example, a ball check valve uses the ball to block reverse flow, but is not a rotor because operating the valve does not involve rotation of the ball. A ball valve (like the butterfly valve, one of a family of valves called quarter turn valves) is a valve that opens by turning a handle attached to a ball inside the valve. ... Plug valves are valves with cylindrical or conically-tapered plugs which can be rotated inside the valve body to control flow through the valve. ... this siamese clappered inlet allows one or two inputs into a deluge gun A check valve is a mechanical device, a valve, that normally allows fluid or gas to flow through it in only one direction. ...


Seat

The valve seat is the interior surface in the body which contacts or could contact the disc to form a seal which should be leak-tight, particularly when the valve is shut (closed). If the disc moves linearly as the valve is controlled, the disc comes into contact with the seat when the valve is shut. When the valve has a rotor, the seat is always in contact with the rotor, but the surface area of contact on the rotor changes as the rotor is turned. If the disc swings on a hinge, as in a swing check valve, it contacts the seat to shut the valve and stop flow. In all the above cases, the seat remains stationary while the disc or rotor moves. The body and the seat could both come in one piece of solid material, or the seat could be a separate piece attached or fixed to the inside of the valve body, depending on the valve design.


Stem

The stem is a rod or similar piece spanning the inside and the outside of the valve, transmitting motion to control the internal disc or rotor from outside the valve. Inside the valve, the rod is joined to or contacts the disc/rotor. Outside the valve the stem is attached to a handle or another controlling device. Between inside and outside, the stem typically goes through a valve bonnet if there is one. In some cases, the stem and the disc can be combined in one piece, or the stem and the handle are combined in one piece.


The motion transmitted by the stem can be a linear push or pull motion, a rotating motion, or some combination of these. A valve with a rotor would be controlled by turning the stem. The valve and stem can be threaded such that the stem can be screwed into or out of the valve by turning it in one direction or the other, thus moving the disc back or forth inside the body. Packing is often used between the stem and the bonnet to seal fluid inside the valve in spite of turning of the stem. Some valves have no external control and do not need a stem; for example, most check valves. Check valves are valves which allow flow in one direction, but block flow in the opposite direction. Some refer to them as one-way valves. this siamese clappered inlet allows one or two inputs into a deluge gun A check valve is a mechanical device, a valve, that normally allows fluid or gas to flow through it in only one direction. ...


Valves whose disc is between the seat and the stem and where the stem moves in a direction into the valve to shut it are normally-seated (also called 'front seated'). Valves whose seat is between the disc and the stem and where the stem moves in a direction out of the valve to shut it are reverse-seated (also called 'back seated'). These terms do not apply to valves with no stem nor to valves using rotors.


Bonnet

A bonnet basically acts as a cover on the valve body. It is commonly semi-permanently screwed into the valve body. During manufacture of the valve, the internal parts were put into the body and then the bonnet was attached to hold everything together inside. To access internal parts of a valve, a user would take off the bonnet, usually for maintenance. Many valves do not have bonnets; for example, plug valves usually do not have bonnets.


Spring

Many valves have a spring for spring-loading, to normally shift the disc into some position by default but allow control to reposition the disc. Relief valves commonly use a spring to keep the valve shut, but allow excessive pressure to force the valve open against the spring-loading, Helical or coil springs designed for tension A spring is a flexible elastic object used to store mechanical energy. ... Relief Valve A relief valve opens to release excess pressure when the pressure is too high to protect the vessel or other equipment from overpressurization. ...


Valve balls

A valve ball is also used for severe duty, high pressure, high tolerance applications. They are typically made of stainless steel, titanium, Stellite, Hastelloy, brass, and nickel. They can also be made of different types of plastic, such as ABS, PVC, PP or PVDF. The 630 foot high, stainless-clad (type 304L) Gateway Arch defines St. ... General Name, symbol, number titanium, Ti, 22 Chemical series transition metals Group, period, block 4, 4, d Appearance silvery metallic Standard atomic weight 47. ... Stellite is also the name of a winning racehorse trained in Scotland, sometimes called The Burr. ... HASTELLOY is the registered trademark name of Haynes International, Inc. ... “Brazen” redirects here. ... For other uses, see Nickel (disambiguation). ... Monomers in ABS polymer Acrylonitrile butadiene styrene, or ABS, (chemical formula (C8H8· C4H6·C3H3N)n is a common thermoplastic used to make light, rigid, molded products such as piping, golf club heads (used for its good shock absorbance), automotive body parts, wheel covers, enclosures, protective head gear, and toys including... PVC may refer to the following: Polyvinyl chloride, a plastic Premature ventricular contraction, irregular heartbeat Permanent virtual circuit, a term used in telecommunications and computer networks Param Vir Chakra, Indias highest military honor. ... Polypropylene lid of a Tic Tacs box, with a living hinge and the resin identification code under its flap Micrograph of polypropylene Polypropylene or polypropene (PP) is a thermoplastic polymer, made by the chemical industry and used in a wide variety of applications, including food packaging, ropes, textiles, stationery, plastic... PVDF, or PolyVinylidine DiFluoride, is a highly non-reactive and pure thermoplastic fluoropolymer. ...


Valve operating positions

Valve positions are operating conditions determined by the position the disc or rotor in the valve. Some valves are made to be operated in a gradual change between two or more positions.


2-way valves

2-port valves are commonly called 2-way valves. Operating positions for such valves can be either shut (closed) so that no flow at all goes through, fully open for maximum flow, or sometimes partially open to any degree in between. Many valves are not designed to precisely control intermediate degree of flow; such valves are considered to be either open or shut, with maybe qualitative descriptions in between. Some valves are specially designed to regulate varying amounts of flow. Such valves have been called by various names like regulating, throttling, metering, or needle valves. For example, needle valves have elongated conically-tapered discs and matching seats for fine flow control. For some valves, there may be a mechanism to indicate how much the valve is open, but in many cases other indications of flow rate are used, such as separate flow meters. Flow measurement is the quantification of bulk fluid or gas movement. ...


In some plants with fluid systems, some 2-way valves can be designated as normally shut or normally open during regular operation. Examples of normally shut valves are sampling valves, which are only opened while a sample is taken. Examples of normally open valves are isolation valves, which are usually only shut when there is a problem with a unit or a section of a fluid system such as a leak. Then, isolation valve(s) are shut in order to isolate the problem from the rest of the system. An Internet leak occurs when a partys confidential intellectual property is released to the public on the Internet. ...


Although many 2-way valves are made in which the flow can go in either direction between the two ports, when a valve is placed into a certain application, flow is often expected to go from one certain port on the upstream side of the valve, to the other port on the downstream side. Pressure regulators are variations of valves in which flow is controlled to produce a certain downstream pressure, if possible. They are often used to control flow of gas from a gas cylinder. A back-pressure regulator is a variation of a valve in which flow is controlled to maintain a certain upstream pressure, if possible. This article is about pressure in the physical sciences. ... Industrial compressed gas cylinders used for oxy-fuel welding and cutting of steel. ...


3-way valves

3-way valves have three ports. 3-way valves are commonly made such that flow coming in at one port can be directed to either the second port in one position or the third port in another position or in an intermediate position so all flow is stopped. Often such 3-way valves are ball or rotor valves. Many faucets are made so that incoming cold and hot water can be regulated in varying degrees to give outcoming water at a desired temperature. Other kinds of 3-port valves can be designed for other possible flow-directing schemes and positions; for example, see Ball valve. A ball valve (like the butterfly valve, one of a family of valves called quarter turn valves) is a valve that opens by turning a handle attached to a ball inside the valve. ...


The "motor valve" on a domestic heating system is an example of a 3-way valve. Depending on demand the motor head rotates the spindle to control the proportion of the flow that goes to the two outlet pipes: One to radiators, one to hot water system. In a conventional system the valve usually sits just after the pump and by the cylinder ("hot tank").


In valves having more than 3 ports, even more flow-directing schemes are possible. For examples, see this external site. Such valves are often rotor valves or ball valves. Slider valves have been used also.


Control

A valve controlled by a wheel (left).
A valve controlled by a wheel (left).

Many valves are controlled manually with a handle attached to the valve stem. If the handle is turned a quarter of a full turn (90°) between operating positions, the valve is called a quarter-turn valve. Butterfly valves, ball valves, and plug valves are often quarter-turn valves. Valves can also be controlled by devices called actuators attached to the stem. They can be electromechanical actuators such as an electric motor or solenoid, pneumatic actuators which are controlled by air pressure, or hydraulic actuators which are controlled by the pressure of a liquid such as oil or water. Actuators can be used for the purposes of automatic control such as in washing machine cycles, remote control such as the use of a centralized control room, or because manual control is too difficult; for example, the valve is huge. Pneumatic actuators and hydraulic actuators need pressurized air or liquid lines to supply the actuator: an inlet line and an outlet line. Pilot valves are valves which are used to control other valves. Pilot valves in the actuator lines control the supply of air or liquid going to the actuators. Image File history File linksMetadata Download high-resolution version (1280x1027, 123 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Valve Metadata This file contains additional information, probably added from the digital camera or scanner used to create... Image File history File linksMetadata Download high-resolution version (1280x1027, 123 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Valve Metadata This file contains additional information, probably added from the digital camera or scanner used to create... A butterfly valve is a type of flow control device, typically used to regulate a fluid flowing through a section of pipe. ... An actuator is a mechanical device for moving or controlling a mechanism or system. ... For other kinds of motors, see motor. ... For other uses, see Solenoid (disambiguation). ... Air pressure can refer to: Atmospheric pressure, the pressure of air environmentally Pressure of air in a system Category: ... Hydraulics is a branch of science and engineering concerned with the use of liquids to perform mechanical tasks. ... This article is about pressure in the physical sciences. ... A Pilot valve is a small valve that controls a limited-flow control feed to a separate piloted valve. ...


The fill valve in a commode water tank is a liquid level-actuated valve. When a high water level is reached, a mechanism shuts the valve which fills the tank. A Commode is a piece of furniture (typically a chair) with a built in chamber pot. ...


In some valve designs, the pressure of the flow fluid itself or pressure difference of the flow fluid between the ports automatically controls flow through the valve. In an open valve, fluid flows in a direction from higher pressure to lower pressure.


Other considerations

Valves are typically rated for maximum temperature and pressure by the manufacturer. The wetted materials in a valve are usually identified also. Some valves rated at very high pressures are available. When a designer, engineer, or user decides to use a valve for an application, he/she should ensure the rated maximum temperature and pressure are never exceeded and that the wetted materials are compatible with the fluid the valve interior is exposed to. For other uses, see Temperature (disambiguation). ... This article is about pressure in the physical sciences. ...


Some fluid system designs, especially in chemical or power plants, are schematically represented in piping and instrumentation diagrams. In such diagrams, different types of valves are represented by certain symbols. abbreviated as P&ID ...


Valves in good condition should be leak-free. However, valves may eventually wear out from use and develop a leak, either between the inside and outside of the valve or, when the valve is shut to stop flow, between the disc and the seat. A particle trapped between the seat and disc could also cause such leakage. An Internet leak occurs when a partys confidential intellectual property is released to the public on the Internet. ...


Types of valves

  • 4-stroke cycle engine valves
  • Aspin valve, a cone-shaped metal part fitted to the cylinder head of an engine.
  • Ball cock, often used as a water level controller (cistern).
  • Ball valve, which is good for on/off control.
  • Bibcock, provides a connection to a flexible hosepipe
  • Blast valve, used to prevent rapid overpressures in a fallout shelter or a bunker.
  • Butterfly valve, particularly in large pipes.
  • Choke valve, a valve that lifts up and down a solid cylinder.
  • Check valve or Non-return valve, allows the fluid to pass in one direction only.
  • Cock, colloquial term for a small valve or a stopcock.
  • Demand valve on a diving regulator.
  • Diaphragm valve, a sanitary valve predominantly used in the pharmaceutical industry
  • Double check valve
  • Duckbill valve
  • A flow control valve maintains a constant flow rate through the valve.
  • Foot valve, a check valve on the foot of a suction line to prevent backflow.
  • Freeze valve, in which freezing and melting the fluid creates and removes a plug of frozen material acting as the valve.
  • Gate valve, mainly for on/off control.
  • Choke valve, Is a heavy duty valve which controls flow to a certain Flow Coefficient (CV) determined by how far the valve is opened, regularly used in the Oil industry.
  • Globe valve, which is good for regulating flow.
  • A heart valve regulates blood flow through the heart in many organisms.
  • Hydraulic valve (diaphragm valve).
  • A leaf valve is a one-way valve consisting of a diagonal obstruction with an opening covered by a hinged flap.
  • Needle valve for gently releasing high pressures.
  • Pilot valves regulate flow or pressure to other valves.
  • Piston valves
  • Plug valve, for on/off control.
  • A poppet valve is commonly used in piston engines to regulate the fuel mixture intake and exhaust. The sleeve valve is another valve type used for this purpose.
  • A pressure reducing valve (PRV), also called pressure regulator, reduces pressure to a preset level downstream of the valve.
  • A pressure sustaining valve, also called back-pressure regulator, maintains pressure at a preset level upstream of the valve.
  • Presta and Schrader valves are used to hold the air in bicycle tires.
  • Relief valve, used to ensure a build up of pressure does not occur.
  • A Reed valve consists of two or more flexible materials pressed together along much of their length, but with the influx area open to allow one-way flow, much like a heart valve.
  • A regulator is used in SCUBA diving equipment and in gas cooking equipment to reduce the high pressure gas supply to a lower working pressure
  • Rotary valves and piston valves are parts of brass instruments used to change their pitch.
  • A saddle valve, where allowed, is used to tap a pipe for a low-flow need.
  • A safety valve or relief valve operates automatically at a set differential pressure to correct a potentially dangerous situation, typically over-pressure.
  • Schrader valves are used to hold the air inside automobile tires.
  • Solenoid valve, an electrically controlled hydraulic or pneumatic valve.
  • Stopcocks restrict or isolate the flow through a pipe of a liquid or gas.
  • Tap (British English), faucet (American English) is the common name for a valve used in homes to regulate water flow.
  • Thermostatic Mixing Valve
  • A three-way valve routes fluid from one direction to another.
  • Some trap primers either include other types of valves, or are valves themselves
  • Vacuum breaker valves prevent the back-siphonage of contaminated water into pressurized drinkable water supplies.

4-stroke engines, of either spark ignition or compression ignition varieties, use poppet valves to allow air (or an air/fuel mixture) into the cylinder and exhaust gases out. ... Aspin valves were first patented by frank Metcalf Aspin in 1937 although the idea has probably been devised before this time. ... A ballcock is a mechanism for filling water tanks, such as those found in flush toilets, while avoiding overflow. ... A ball valve (like the butterfly valve, one of a family of valves called quarter turn valves) is a valve that opens by turning a handle attached to a ball inside the valve. ... A bibcock, also called a sillcock, is commonly used to provide hose connections outside of buildings, for use in gardening, watering lawns, washing cars, and so on. ... A garden hose or hosepipe is a kind of hose which is used for watering plants in a garden or a lawn. ... A blast valve is used to protect a shelter, such as a fallout shelter or bunker, from the effects of sudden outside air pressure changes. ... A sign pointing to an old fallout shelter in New York City. ... Bunkers in Albania A bunker is a defensive military fortification. ... A butterfly valve is a type of flow control device, typically used to regulate a fluid flowing through a section of pipe. ... A choke valve is sometimes installed in the carburetor internal combustion engines. ... this siamese clappered inlet allows one or two inputs into a deluge gun A check valve is a mechanical device, a valve, that normally allows fluid or gas to flow through it in only one direction. ... Indoor Tap - commonly found in the bathroom/laundry and/or kitchen. ... A stopcock is a valve used to restrict or isolate the flow through a pipe of a liquid or gas. ... A diving regulator is a gas pressure regulator used as a part of the Aqualung apparatus supplying SCUBA divers with breathing gas at ambient pressure. ... A gas pressure regulator has one or more valves in series, which let the gas out of a gas cylinder in a controlled way, lowering its pressure at each stage. ... Diaphragm valves (or membrane valves) consists of a valve body with two or more ports, a diaphragm, and a saddle or seat upon which the diaphragm closes the valve. ... A double check valve or double check assembly (DCA) is a backflow prevention device designed to protect water supplies from contamination. ... A duckbill valve is a valve, manufactured from rubber or synthetic elastomer, and shaped like the beak of a duck. ... A flow control valve regulates the flow or pressure of a fluid. ... Freeze plugs are subset of the plugs on a car engine cylinder block (core plugs). ... A gate valve is a valve that opens by lifting a round or rectangular gate out of the path of the fluid. ... A choke valve is sometimes installed in the carburetor internal combustion engines. ... The flow coefficient of a device is a relative measure of its efficiency at allowing fluid flow. ... The Oil industry brings to market what is currently considered the lifeblood of nearly all other industry, if not industrialized civilization itself. ... A Globe valve is a device (specifically a type of valve) for regulating flow in a pipeline, consisting of a movable disk-type element and a stationary ring seat in a generally spherical body. ... Grays Fig. ... Hydraulics is a branch of science and engineering concerned with the use of liquids to perform mechanical tasks. ... A leaf valve is a one-way valve (check valve) consisting of a diagonal obstruction with an opening covered by a hinged flap. ... A needle valve is a type of valve usually used in flow metering applications. ... A Pilot valve is a small valve that controls a limited-flow control feed to a separate piloted valve. ... 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. ... Plug valves are valves with cylindrical or conically-tapered plugs which can be rotated inside the valve body to control flow through the valve. ... A poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. ... Components of a typical, four stroke cycle, DOHC piston engine. ... Look up exhaust in Wiktionary, the free dictionary. ... piston engine Bristol Perseus The sleeve valve is a type of valve mechanism for piston engines which have traditionally relied on the more common poppet valve. ... A pressure reducing valve (PRV) is a device for reducing the input pressure of a gas or liquid to a predetermined output pressure. ... The Presta valve is a valve (commonly) found in high pressure road style bicycle tyres. ... A schrader valve on a bicycle tire. ... For other uses, see Bicycle (disambiguation). ... Firestone tire This article is about pneumatic tires. ... Relief Valve A relief valve opens to release excess pressure when the pressure is too high to protect the vessel or other equipment from overpressurization. ... Reed valves consist of thin flexible metal or fiberglass strips fixed on one end that open and close upon changing pressures across opposite sides of the valve much like heart valves do. ... A gas pressure regulator has one or more valves in series, which let the gas out of a gas cylinder in a controlled way, lowering its pressure at each stage. ... See also rotary feeder airflow of rotary valve in two positions A rotary valve is a type of valve in which the rotation of a passage or passages in a transverse plug regulates the flow of liquid or gas through the attached pipes. ... 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. ... A saddle valve is a valve used to supply liquid where a low volume, low pressure stream is required. ... Oxygen Safety Valve A safety valve is a valve mechanism for the automatic release of a gas from a boiler, pressure vessel, or other system when the pressure or temperature exceeds preset limits. ... Relief Valve A relief valve opens to release excess pressure when the pressure is too high to protect the vessel or other equipment from overpressurization. ... A schrader valve on a bicycle tire. ... “Car” and “Cars” redirect here. ... Firestone tire This article is about pneumatic tires. ... A solenoid valve is an electromechanical valve for use with liquid or gas controlled by running or stopping an electrical current through a solenoid, which is a coil of wire, thus changing the state of the valve. ... A stopcock is a valve used to restrict or isolate the flow through a pipe of a liquid or gas. ... Indoor Tap - commonly found in the bathroom/laundry and/or kitchen. ... Thermostatic Mixing Valves (TMVs) blend hot water (stored at temperatures high enough to kill bacteria) with cold water to ensure constant, safe outlet temperatures preventing scalding. ... A trap primer is a plumbing device or valve that adds water to traps. ... Not to be confused with Psiphon. ...

Images

See also

Backwater can mean: Water held or pushed back by or as if by a dam or current. ... Piping is used to convey fluids (usually liquids and gases but sometimes loose solids) from one location to another. ... A plumber wrench for working on pipes and fittings A complex arrangement of rigid steel piping, stop valves regulate flow to various parts of the building. ... Variable valve timing, or VVT, is a generic term for an automobile piston engine technology. ... A zone valve is a specific type of valve used to control the flow of water or steam in a hydronic heating or cooling system. ... Look up Wog in Wiktionary, the free dictionary. ... Plastic Pressure Pipe Systems have been in use since the 1950s. ... The speedy deletion of this page is contested. ...

External links

  • Valve Sizing and Selection
  • Flow in known Design Types of Shut-off Valves

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