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12 Jun

Many machines and processes use a fluid for developing a force to move or hold an object, or to control an action. The term hydraulic refers to a liquid. A number of fluids can be used for developing the force.  In a hydraulic system, oil, water, or other liquids can be used.  Oil is the [...]


7 Jun

The purpose of an air compressor is to provide a continuous supply of pressurized air.  This chapter will describe the various types of compressors and their basic operation.
Air compressors of various designs are used widely throughout DOE facilities in numerous applications.  Compressed air has numerous uses throughout a facility including the operation of equipment  and [...]

Pilot-Operated Relief Valves

7 Jun

Pilot-operated relief valves are designed to maintain pressure through the use of a small passage to the top of a piston that is connected to the stem such that system pressure closes the main relief valve.  When the small pilot valve opens, pressure is relieved from the piston, and system pressure under the disk opens [...]

Piston Check Valves

7 Jun

A piston check valve, illustrated in Figure 25, is essentially a lift check valve. It has a dashpot consisting of a piston and cylinder that provides a cushioning effect during operation. Because of the similarity in design to lift check valves, the flow characteristics [...]

Diaphragm Construction

7 Jun

The operating mechanism of a diaphragm valve is not exposed to the media within the pipeline. Sticky or viscous fluids cannot get into the bonnet to interfere with the operating mechanism. Many fluids that would clog, corrode, or gum up the working parts of most other types of valves will pass through a diaphragm valve [...]