Directional control valve

"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and 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." [Directional control valve. Wikipedia]
This example engineering drawing showing the directional control valve usage with fixed volume pump and hydraulic cylinder is redesigned using the ConceptDraw PRO diagramming and vector drawing software from Wikimedia Commons file: DCV 19.jpg.
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The fluid power equipment drawing example "Directional control valve" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

This example engineering drawing showing the hydraulic directional control valve usage with floating motor and pressure compensated pump is redesigned using the ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: DCV 17.jpg.
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"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and 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. ...
The spool (sliding type) consists of lands and grooves.The lands block oil flow through the valve body. The grooves allow oil or gas to flow around the spool and through the valve body. There are two fundamental positions of directional control valve namely normal position where valve returns on removal of actuating force and other is working position which is position of a valve when actuating force is applied. There is another class of valves with 3 or more position that can be spring centered with 2 working position and a normal position. ...
Directional control valves can be classified according to:
(1) number of ports;
(2) number of positions;
(3) actuating methods;
(4) type of spool." [Directional control valve. Wikipedia]
The fluid power equipment drawing example "Directional control valve" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

A simple hydraulic schematic showing apparatus for testing the strength of a hydraulic hose splice.
Water enters through normally closed solenoid valve (1) and passes through intake flow meter (2) to high pressure pump (4). Intake water pressure is monitored by pressure gauge (3). The hose to be tested connects between pump (4) and normally open solenoid activated drain valve (7). To test the hose, pump drive motor (5) is turned on, the solenoid of drain valve (7) is activated, closing the valve, and the pump is run to pressurize the hose. Test pressure is monitored by gauge (6). When the test is complete or the hose fails, the solenoid of drain valve (7) is deactivated, opening valve and discharging water, depressurizing the system. All components are operated electrically by a remote control circuit so that the operator may perform the test from a protected location, monitoring it with a camera and video monitor.
This hydraulic schematic example was redrawn using ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: Hydraulic schematic.jpg.
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This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
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The hydraulic schematic example "Apparatus for testing the strength of a hydraulic hose splice" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

The vector stencils library "Valve assembly" contains 141 symbols of pressure and flow regulators, flow direction indicators, controls, and symbols to design flow paths of control valves.
Use these valve assembly shapes to design the engineering drawings of hydraulic and pneumatic valve assemblies in fluid power systems.
"Control valves are valves used to control conditions such as flow, pressure, temperature, and liquid level by fully or partially opening or closing in response to signals received from controllers that compare a "setpoint" to a "process variable" whose value is provided by sensors that monitor changes in such conditions.
The opening or closing of control valves is usually done automatically by electrical, hydraulic or pneumatic actuators. Positioners are used to control the opening or closing of the actuator based on electric, or pneumatic signals.
A control valve consists of three main parts in which each part exist in several types and designs: Valve's actuator, Valve's positioner, Valve's body.
" [Control valves. Wikipedia]
The shapes example "" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

The vector stencils library "Valves" contains 91 symbols of piping and plumbing valves.
"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.
People in developed nations use valves in their daily lives, including plumbing valves, such as taps for tap water, gas control valves on cookers, small valves fitted to washing machines and dishwashers, safety devices fitted to hot water systems..." [Valve. Wikipedia]
Use the design elements library "Valves" to draw building plans, schematic diagrams, blueprints, or technical drawings of industrial piping systems; process, vacuum, and fluids piping; hydraulics piping; air and gas piping; materials distribution; and liquid transfer systems using the ConceptDraw PRO diagramming and vector drawing software.
The shapes library "Valves" is included in the Plumbing and Piping Plans solution from the Building Plans area of ConceptDraw Solution Park.

"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 Mac 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

"A hydraulic circuit is a system comprising an interconnected set of discrete components that transport liquid. The purpose of this system may be to control where fluid flows (as in a network of tubes of coolant in a thermodynamic system) or to control fluid pressure (as in hydraulic amplifiers).
... hydraulic circuit theory works best when the elements (passive component such as pipes or transmission lines or active components such as power packs or pumps) are discrete and linear. This usually means that hydraulic circuit analysis works best for long, thin tubes with discrete pumps, as found in chemical process flow systems or microscale devices." [Hydraulic circuit. Wikipedia]
The engineering drawing example "Hydraulic circuits" was redrawn using ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: Hydraulic circuits.png.
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This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
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The engineering drawing example "Hydraulic circuits" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.