The closed-center circuit shown in Fig. 4.18 has a variable displacement pump like that shown in Fig. 4.15. The compensator valve spring is a 2500…
The fixed displacement pump shown in Fig. 4.3 delivers 20 GPM continuously. The relief valve is set on 2500 psi. When the DCV is manually…
Load sensing was developed to improve the efficiency of a circuit. It requires a variable displacement pump; thus, it is appropriate to discuss it here.…
1. A backhoe operator controls the speed of the cylinder, which extends the bucket by cracking open the DCV controlling flow of the cylinder. Describe…
A brake valve performs the same function as a counterbalance valve, but it is designed to overcome a key disadvantage. An example will illustrate this…
The counterbalance valve, also called a holding valve, is used to prevent a weight from falling uncontrollably. As an example, consider a press with a…
The sequence valve and pressure-reducing valve have some similar features. It is instructive to compare their symbols side by side (Fig. 3.20). Both valves are…
The counterbalance valve and brake valve have similar symbols (Fig. 3.26). The single difference is that the brake valve has a remote pilot line in…
A pressure-reducing valve does not allow pressure downstream of the valve to exceed the set point. Suppose the workpiece must be clamped with two clamps.…
The sequence valve is used to ensure that a certain pressure level is achieved in one branch of the circuit before a second branch is…