Title: Assignment: Lab 8 - Hydraulic Relief Valve Applications
Course: Canvas Practice Course

LAP 3 - Hydraulic Relief Valve Operation

Introduction:

Relief valves are used in almost every hydraulic circuit. In Basic Hydraulics, LAP 4, you learned that there are two relief valve designs commonly used in hydraulic applications, direct-operated and pilot-operated, and how they limit pressure in the circuit. Besides limiting the pressure, there are other ways in which these valves are used. In this LAP, you will learn more about the operation of the relief valve and its other applications.

Objectives:

- Explain the advantage of a pilot-operated relief valve.
- Describe the operation of a pilot-operated relief valve and give its complete schematic symbol.
- Describe the function of the vent port of a pilot-operated relief valve.
- Describe two methods of pump unloading and give an application of each.
- Describe the operation of a remote-controlled relief valve circuit.
- Describe multiple pressure relief valve circuit.

Materials and equipment:

1 ea. 85-BH Basic Hydraulic Training System

1 ea. 85-HPS Hydraulic Power Unit

1 ea. 85-IH Intermediate Hydraulic Training System

1 ea. Allen wrench set

1 ea. LAP 3 - Intermediate Book

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