Pumps reciprocating piston compressor

In much the same manner as pumps, compressors are classified as one of two general classes positive displacement or dynamic (see Figure 3-68) [23]. These two general classes of compressors are the same as that for pumps. The positive displacement class of compressors is an intermittent flow device, which is usually a reciprocating piston compressor or a rotary compressor (e.g., sliding vane, screws, etc.). The dynamic class of compressor is a continuous flow device, which is usually an axial-flow or centrifugal compressor (or mix of the two). 

The delivery system can either be a syringe pump, reciprocating piston pump, or gas compressor. Both syringe and reciprocating piston pumps are available on analytical-scale commercial instrumentation. These are used for analytical-scale extractions, while gas compressors are typically used for large-scale... 

Reciprocating positive displacement machines exist in versions such as piston pumps, membrane pumps, piston compressors, and membrane compressors. These machines achieve the highest pressures and the pumps are additionally able to reach a high conveying precision. The main reason for these features is the leakproof discharge chambers (operating areas of the positive displacement machines). 

The most used mechanical vacuum pumps or compressors are reciprocating, liquid-ring, rotary-vane, rotary blower, rotary piston, and diaphragm. 

Figure 11-21D. Helical rotors refrigerant compressors. (1) Cutaway of a 100-ton intermediate compressor. The intermediate Helirotor compressor has only three moving parts the two rotor assemblies and the capacity controlling slide valve. The general purpose Helirotor compressor has only four moving parts two rotor assemblies, the variable unloader valve, and the step unloader valve. Unlike reciprocating compressors, the Trane Helirotor compressor has no pistons, connecting rods, suction and discharge valves, or mechanical oil pump.

The motion of the piston rod is reciprocating through this packing as contrasted to the rotating motion of the centrifugal compressor or pump shaft. In many applications, it is important to prevent any part of the shaft that has heen inside the cylinder and exposed to the gas from being... 

Devices which are used for transporting fluids (liquids and gases) may be divided into pumps, ejectors, injectors, elevators, conveyors, air and gas pressure devices (such as acid eggs, air lifts, pulsometers etc). Pumps may be divided into piston (reciprocating), centrifugal, propeller, rotary-displacement, density, impact and momentum and turbine pumps. Pumps which are used for compressing gases are called "compressors ... 

RECIPROCATING COMPRESSOR - Compressor which uses a piston and cylinder mechanism to provide pumping action. 

Piston pump Consists of one or more pistons reciprocating inside one or more cylinders. Similar to an air compressor, except that air is discharged to the atmosphere. More expensive, but capable of delivering a satisfactory CFM output. 

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