An expander (usually an electric motor) that expands a gas in a variable volume and outputs external work for cooling
Braking absorbs external work). The expansion machine is divided into vertical and horizontal two kinds. The most used is standing
Type structure, crankshaft, connecting rod, cross head, piston, intake valve and exhaust valve, etc., are moving.
Parts are respectively installed in the fuselage, cylinder and middle seat, and the Zuo is approximate to reciprocating piston compression
Basic information: A6410 EMERSON Mechanical Expansion Unit
Piston type
An expander that causes gas to expand in a variable volume to output external work for cooling (usually absorbed by motor braking). The expansion machine is divided into vertical and horizontal two kinds. The most used is vertical structure, crankshaft, connection
The rod, cross head, 瘥 intake valve and exhaust valve are moving parts, respectively installed in the body cylinder and the middle seat, their functions are similar to reciprocating piston compressor, but the intake and exhaust valves are inlet and exhaust convex
Wheel timing open and close. Piston expansion machine due to the existence of inlet and exhaust valve flow resistance, complete expansion, friction heat external heat and internal heat exchange caused by cold loss, the general adiabatic efficiency is: high-pressure expansion machine
65 ~ 85%, medium pressure expansion machine 60~ 70%. In the 1950s, valveless and single-valve expanders without CAM transmission mechanisms appeared successively, reducing the moving parts of the expander and improving the reliability of the machine
It has been widely used in small cryogenic equipment. In the 1960s, polytetrafluoro2-ene sealing elements with fillers were used instead of oil-lubryed metal sealing elements to avoid lubricating oil being brought into deep and low
Warm rectification or liquefaction area to ensure safety.
Turbine type
Schematic diagram of turbo-type expansion machine
An expander that transmits energy by changing the velocity energy of a gas as it expands. The expander is divided into single stage and double stage, vertical and horizontal, impulse and reaction type. - Generally use a single stage centripetal flow reaction, transmission
The external work is absorbed by the generator, blower or oil brake. It is similar to a single-stage centrifugal compressor, but has an adjustable flow (adjustable blade). Low speed bearing oil forced lubrication, high
Gas bearings are used for speed. Turbine expander has nozzle loss, impeller loss, speed loss, disc friction loss, leakage loss, channeling loss and external thermal intrusion loss, the general adiabatic efficiency is
Pressure expansion machine 65 ~ 75%, low pressure expansion machine 75 ~ 85%. In the 1960s, it was made into a liquid expansion machine, mostly used in natural fusible separation equipment.
