Hydraulic Valve Types and Working Methods
Hydraulic Valve Types and Working Methods
1. Duties of Valves
• Turns fluid path on and off.
• Changes the direction the fluid will go.
• Sends the fluid to the tank.
• By controlling the flow of the fluid,
adjusts the speed.
• It protects the circuit elements against high pressures.
It sends the fluid with rising pressure to the tank.
• By controlling the pressure of the fluid, the circuit elements
allows it to work at certain pressures.
• The pressure, flow and direction of the fluid at a certain time
checks at intervals.
Some valves have one or more of the tasks listed above.
Can.
2. Pressure Control Valves
The fluid used in the pressure lines of hydraulic systems
are the valves that ensure the pressure to be at the desired value.
Types According to the Places Used;
2.1. Pressure Safety valves
It will be enough to beat the resistance formed for the job to happen
allow much pressure to build up, on it
at the possible resistance (= end of stroke), it sets a limit on pressure.
2.2. Pressure reducing valves
It is desired to operate at different pressures in hydraulic circuits,
multiple user elements (cylinder, Hydromotor
) and different user elements
may need to operate at pressures. Pressure in such cases
reducing valves are used. It is normally open.
When the pressure rises, it turns off. Two-way and three
There are different types of ways.
2.3. Pressure sequencing valves
Pressure sequencing valves are hydraulic
multiple cylinders in the circuit,
user elements such as engines at different times and pressures
used to run. Working principle Pressure safety
It is similar with valves. It is normally closed. Wanted
It opens at pressure and activates other user elements.
2.4. Discharge valves
To send the hydraulic fluid to the Hydraulic Tank
Normally closed valve opens when warning is received
and sends the fluid to the tank.
3. Directional Control Valves
When and which path of the fluid in hydraulic circuits
are the valves that determine the need. Flow on demand
they change their way; They open and close the flow path when desired
3.1. Schematic View of Directional Control Valves
• Each position of the valve should be indicated with a square.
• Fluid passage directions are indicated by arrows.
• Closed roads are determined by a horizontal line.
• Valve connections are indicated by dashes.
• Marking valve positions; valve positions from left
it is marked with letters to the right. In three-position victories
center position indicated by 0
.4. Lettering of valve connections;
• P = Pressure line A, B, C .... = Work line or working line
• R, S, T = Warehouse (return) line
• X, Y, Z = Pilot (warning) line
• L = Leak line
3.5. Identification of directional control valves;
• 2/2 = Number of routes / Number of locations
• When 3/2 valve definition is made, the valve has 3 way, 2
understood to be in position.
3.6. Normal positions of vafas;
• Valves in hydraulic circuit drawings, in their normal positions
is drawn and lettered.
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4. Valve Malfunctions
There are some problems that happen repeatedly during the study.
The most common of these are;
Bad Control Element
Excessive Leak
Broken or Broken Springs
Adhesion or Stiffness
Cracked or Broken Parts
Most valve failures are caused by problems elsewhere in the system.
occurs due to Repair unless the actual fault is corrected
You can expect recurrence of faults with valves that have been replaced or replaced.
General inspection of parts; bulge, cut, rough, notch,
malfunctions such as cracks, wear marks or bent parts
Includes a visual inspection.
Laterally to a flat surface as shown in the figure
place and roll. a wobble that shows strain
visually inspect whether or not.
Valve Malfunction Symptoms can appear in the following ways.
Mud: Oxidation due to overheating of the hydraulic fluid
substance formed with.
Scratch: On the surface of a valve by high pressure fluid
small grooves formed by abrasion.
Knock: The control tip due to insufficient or over current
constantly hitting the solenoid body
noise, murmur, buzz.
Always when you remove a valve for repair or maintenance
even if all seals look good
also insert a new one.
For detailed information, you can reach by e-mail at [email protected].