16. Guide Specifications SPRAY EJECTOR The ejector pump is used to return oil on water cooling chiller with which low-pressure oil can be returned without energy loss.
SPRAY-TYPE EVAPORATOR The evaporator is shell and tube heat exchanger, the special internal structure will make liquid refrigerant spray on the outer wall of heat exchanger tube which will achieve high heat transfer efficiency the evaporator temperature is 5.4~7.2°F(3~4°C) higher than dry-type evaporator, the designed pressure of the evaporator is 145psig(1.0MPa.) The Evaporator is designed and tested in accordance with ASME. The shell is insulated 3/4inch insulation (K=0.26).
CONDENSER Condenser is shell and tube heat exchanger ,the special internal structure refreshed original condenser, which can make condensation temperature be 1.8~3.6°F(1~2°C) lower than that of general units, the designed pressure of condenser is 145psig(1.0MPa.) The Evaporator is designed and tested in accordance with ASME.
OIL SEPARATOR Oil separator range is filter-type oil separator, its structure is very simple, however, the ratio of oil and circulated refrigerant's less than 0.05% when separated.
ECONOMIZER AND REGENERATOR The mid-pressure saturation flashing gas and liquid refrigerant are separated by economizer, saturation flashing gas enter compressor to join two-stage compression, which can increase the unit efficiency, the separated midpressure saturation liquid refrigerant will be super-cooled by heat exchanger in regenerator then the pressure of refrigerant will be dropped by throttling, these can improve the unit's efficiency effectively. The heat exchanger (evaporator, condenser) and reservoir are manufactured and checked according to national standards. LGE Corporation will supply complete information about pressure vessel when units are for sale.
UNIT CONTROL Unit controls of the LGE water cooled screw chiller shall include following benefits and features.
Adaptive Chiller Control and Higher Level Protection. • The latest chiller control technologies provide enhanced operations of the chiller. The chiller control system is based on recent PLC (Programmable Logic Controller) technology. Because the PLC is designed to be compatible with several electromagnetic interferences and also compatible with severe ambient conditions, the unit has reliable controllability in any conditions. • The adaptive chiller control is designed to operate the unit to withstand sever conditions and maintain its operation. • Along with the adaptive control, the control also provides higher level protection through multiple protective devices. For example triple protective devices are used for the detection of abnormal oil circulation. The control system continues to monitor the hazardous conditions of the unit, and shutdown the unit to protect the unit safely when any condition meets safety limit.
59 Water-Cooled Screw Chiller Air-Cooled Screw