This site uses cookies. By continuing to browse the ConceptDraw site you are agreeing to our Use of Site Cookies.
"Directional control valves route the fluid to the desired actuator. They usually consist of a spool inside a cast iron or steel housing. The spool slides to different positions in the housing, and intersecting grooves and channels route the fluid based on the spool's position. The spool has a central (neutral) position maintained with springs; in this position the supply fluid is blocked, or returned to tank. Sliding the spool to one side routes the hydraulic fluid to an actuator and provides a return path from the actuator to tank. When the spool is moved to the opposite direction the supply and return paths are switched. When the spool is allowed to return to neutral (center) position the actuator fluid paths are blocked, locking it in position. Directional control valves are usually designed to be stackable, with one valve for each hydraulic cylinder, and one fluid input supplying all the valves in the stack. Tolerances are very tight in order to handle the high pressure and avoid leaking, spools typically have a clearance with the housing of less than a thousandth of an inch (25 µm). The valve block will be mounted to the machine's frame with a three point pattern to avoid distorting the valve block and jamming the valve's sensitive components. The spool position may be actuated by mechanical levers, hydraulic pilot pressure, or solenoids which push the spool left or right. A seal allows part of the spool to protrude outside the housing, where it is accessible to the actuator. The main valve block is usually a stack of off the shelf directional control valves chosen by flow capacity and performance. Some valves are designed to be proportional (flow rate proportional to valve position), while others may be simply on-off. The control valve is one of the most expensive and sensitive parts of a hydraulic circuit." [Hydraulic machinery. Wikipedia]
The Windows template "Hydraulic 4-ported 3-position valve" for the ConceptDraw PRO diagramming and vector drawing software is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.
www.conceptdraw.com/ solution-park/ engineering-mechanical
Hydraulic directional control valve
Hydraulic directional control valve,  valve, three-position, pneumatic valve symbols, hydraulic valve vector stencils, four-port, fluid power symbols
The vector stencils library "Valves and fittings" contains 104 symbols of valve components.
Use these icons for drawing industrial piping systems; process, vacuum, and fluids piping; hydraulics piping; air and gas piping; materials distribution; and liquid transfer systems.
"A valve is a device that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically valves fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure.
The simplest, and very ancient, valve is simply a freely hinged flap which drops to obstruct fluid (gas or liquid) flow in one direction, but is pushed open by flow in the opposite direction. This is called a check valve, as it prevents or "checks" the flow in one direction. ...
Valves are found in virtually every industrial process, including water & sewage processing, mining, power generation, processing of oil, gas & petroleum, food manufacturing, chemical & plastic manufacturing and many other fields. ...
Valves may be operated manually, either by a handle, lever, pedal or wheel. Valves may also be automatic, driven by changes in pressure, temperature, or flow. These changes may act upon a diaphragm or a piston which in turn activates the valve, examples of this type of valve found commonly are safety valves fitted to hot water systems or boilers.
More complex control systems using valves requiring automatic control based on an external input (i.e., regulating flow through a pipe to a changing set point) require an actuator. An actuator will stroke the valve depending on its input and set-up, allowing the valve to be positioned accurately, and allowing control over a variety of requirements." [Valve. Wikipedia]
The example "Design elements - Valves and fittings" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Chemical and Process Engineering solution from the Engineering area of ConceptDraw Solution Park.
Valves and fittings symbols
Valves and fittings symbols, wedge gate valve, valve manifold, tundish, swivel joint, strainer, stop check valve, soldered, solvent, socket, spigot, socket,  spigot, socket weld, sleeve joint, separator, screwed sleeve, screwed joint, screw-down valve, screw-down check valve, relief valve, relief angle valve vacuum, relief angle valve pressure, reel valve, reducing valve, reducer, powered valve, plug valve straight through, plug valve T point, plug valve L point, plug valve 3 way, plug valve, parallel slide valve, open vent, needle valve, lock-shield valve, liquid seal, joint, hydrant, globe valve, gate valve, float operated valve, flanged valve, flanged joint, bolted joint, flame arrester, exhaust silencer, exhaust head, end cap socket and spigot, end cap screwed, end cap quick release, end cap flanged and bolted, end cap fillet welded, end cap butt welded, end cap	screwed and plugged, end cap, electrically insulated, electrically bonded, drain silencer, diaphragm valve, check valve, characterized port valve, butterfly valve, butt weld, bursting disc, bell mouth, ball valve, angle valve, Y strainer, 3-way plug valve,