Where is the load sensing valve located?
The load sensing valve is mounted to the chassis of the vehicle, the control cable together with the spring is mounted an a bracket bolted or welded to the axle. The control cable is secured to the control lever of the load sensing valve by means of a clamp.
What does a load sensing valve do?
Load-sensing describes a type of variable pump control used in open circuits. It is also termed this because the load-induced pressure downstream of an orifice is sensed and pump flow is adjusted to maintain a constant pressure drop (and therefore flow) across the orifice.
How do you adjust a load sensing valve?
Basic adjustment of the load sensing valve Apply a pressure of 6.0 bar at port 1 and measure the modulated pressure at port 2. If the basic adjustment is correct, P2 must be equal to P1. If this is not the case, the difference between P1 and P2 must be adjusted until equal.
How do you adjust a brake proportioning valve?
Use light pedal pressure, and as an extra precau- tion, move the lever to Position 7 (lever-type), or rotate adjusting knob in a clockwise direction (screw-type), to reduce internal pressure. The proportioning valve can be used to reduce brake line pressure, but will not increase it.
How does a load sensing pump work?
A load sensing pump has a small control hose connected to its load sensing compensator. The other end of this hose will connect to a “LS” port on the directional valve bank. This allows changes in working pressure at the actuator connected to the valve bank to be sensed back at the pump.
How do you know if a proportioning valve is bad?
First, you might notice your car is taking a nose dive when you suddenly apply the brakes. Then your car may not stop fast enough. If your rear wheels lock up easily, especially when you drive on wet surfaces, it is a good sign your proportioning valve is going bad.
What is a load sensing hydraulic valve?
Load sensing hydraulics is a technology that automatically adjusts pressure and flow rate based on the amount of fluid passing through a metered orifice. This feedback calibrates the hydraulic flow in a continuous process. Hydraulic equipment is commonly used in trenchless construction operations.
How does a load sensing hydraulic pump work?
How do you know if your proportioning valve is bad?
How is a proportioning valve diagnosed?
Pressure gauges are the best way to diagnose a failed proportioning valve. There will be a gage installed into the front and rear hydraulic circuits. Start the vehicle, and apply the brake pedal with heavy pedal pressure to duplicate a panic braking situation. The front and rear pressures should be different.