Screw type water chiller
Screw type water chiller is a screw compressor, the refrigerant from the evaporator of the unit is a gaseous refrigerant; after adiabatic compression by the compressor, it becomes a high temperature and high pressure state. The compressed gas refrigerant is cooled and condensed at equal pressure in the condenser. After condensation, it changes into a liquid refrigerant, and then expands to a low pressure through a throttle valve and becomes a gas-liquid mixture. Among them, the liquid refrigerant under low temperature and low pressure absorbs the heat of the substance to be cooled in the evaporator and becomes a gaseous refrigerant again. The gaseous refrigerant re-enters the compressor through the pipeline to start a new cycle.
Screw chiller should pay attention to observe the suction and discharge pressure, suction and discharge temperature, oil temperature and oil pressure, and record regularly. The requirement meter is yes. During operation, due to a certain protection action, it will automatically stop, and the cause of the fault must be found out before it can be turned on. It is allowed to switch on again by changing their set value or shielding the fault.
When the screw chiller is shut down due to a sudden power failure, the compressor may reverse due to the bypass solenoid valve B cannot be opened. At this time, the suction shut-off valve should be closed quickly to reduce the reverse. If the machine is shut down for a long time in a low temperature season, the water in the system should be drained to avoid freezing damage to the equipment.
If the screw chiller is turned on in the low temperature season, first turn on the oil pump, and press the motor to rotate the steering wheel to move the coupling to make the oil circulate in the compressor and fully lubricate. This process must be performed in manual startup mode; if it is Freon refrigeration Before starting the machine, the oil heater must be turned on to heat the lubricating oil, and the oil temperature must be above 25°C.
If the screw chiller is shut down for a long time, the oil pump should be turned on every 10 days or so. There is lubricating oil in all parts of the compressor, and each time the oil pump is turned on for 10 minutes; the compressor is turned on every 2 to 3 months, 1 time each time Hours, the moving parts will not stick together. Before starting each time, turn the compressor a few times to check whether the compressor is jammed and distribute the lubricating oil evenly.