Operation requirements of refrigerant oil cooler in ammonia refrigeration
① the ammonia refrigeration system shall be installed correctly to ensure smooth liquid supply and gas return;
② the content of oil must be reduced on the working medium side: in the ammonia refrigeration system, although the compressor exhaust passes through the oil separator, some lubricating oil will inevitably be entrained. After cooling and condensation, the oil will flow into the siphon tank together with the refrigerant liquid. If the siphon tank does not discharge oil in time, some lubricating oil will enter the oil cooler. Because the oil is difficult to be taken away, the oil will accumulate in the In the tube side of the oil cooler, the heat exchange area is occupied, which affects the heat exchange. Causes high oil temperature. Therefore, in the operation of the ammonia refrigeration system, it is necessary to drain oil from the siphon tank with the daily inch. If some lubricating oil has entered the oil cooler, it is necessary to drain the tube side of the oil cooler.
When draining the refrigerant cooling oil cooler, close the liquid inlet valve of the oil cooler first. Start the compressor, use the exhaust temperature to heat the working medium left in the oil cooler to make it evaporate. When the oil temperature reaches about 60 ℃, stop the compressor and close the oil cooling return valve. Connect the oil drain valve on the oil cooler with the pressure relief pipe to drain oil directly or through the oil collector.
③ pay attention to the cleanliness of oil.
④ regularly open the upper oil cooling air extraction valve.
④ the oil temperature of the refrigerant cooling oil cooler is greatly affected by the condensation temperature (condensation pressure). During operation in summer, the condensation pressure can be properly reduced, and the oil temperature can be ensured not to be too high by frequent venting; in winter, the condensation pressure can be properly increased or the flow of working medium can be controlled to ensure the normal oil temperature.