During the compression stroke piston machine, the gas becomes hotter and a little oil on the wall of the cylinder will be held, with the discharge of gas. Some oil carry-over will occur with all types of compressors lubrication, and in small stand-alone systems, he quickly finds his way back to the compressor. Start after a long period of inactivity can lead to a large number remainder of the oil within a short period of time in connection with the foam at the mouth. Larger and more complex systems with remote evaporators oil it is desirable to match the separation of oil in the discharge line in order to reduce rolling into the system (see Fig. 5.5).
Hot gas injection spiral of falling lose most of the oil on the surface under the action of centrifugal force. Some 95-98% of oil are accumulated can be separated from the hot gas and sink to the bottom and can be returned to the crankcase. The oil return line is controlled by a float valve, or he can talk. In any case, the account device must be backed up by a solenoid valve to provide tight shut-off at a stop of the compressor, because as a separator at discharge pressure and oil in the crankcase of the compressor suction pressure.
Completion of the work under high pressure in the gas separator, it will be cool, and some will condense into a liquid for the dilution of the oil remaining in the bottom.
When the compressor restarts, this diluted oil will pass into the sump. In order to limit this dilution, heater, usually installed in the base of the separator in large installations.
Oil-injected screw compressors invariably have oil separators and these handles continuous oil carry-over from the fuel process. They often built into the compressor Assembly, especially with semi-hermetic air conditioning types. Recycling ago injection ports and bearings constantly. For low-temperature screw compressors oil is commonly cooled in the recycling process. For installations that can be very sensitive to oil accumulations, in two phases : oil separator can be installed and up to 99.7% of the accumulated oil can be removed. However, effective separation process, small quantities of oil will be carried forward in the design of the system must accommodate oil circulation.....