The general layout principle of the suction pipe in the cold storage

The general layout principle of the suction pipe in the cold storage

Recently, a small partner left a message asking about the general layout principles of the suction pipe in the cold storage. Today, the editor of okmarts.com will popularize this knowledge for everyone.

The general layout principle of the suction pipe in the cold storage

　　 When arranging the suction pipe in the cold storage project, in addition to ensuring the oil return, it is also necessary to prevent the refrigerant liquid from rushing into the compressor. Because the expansion valve often cannot be closed tightly when the compressor is stopped, part of the refrigerant liquid leaking into the evaporator can be flushed into the compressor when the compressor is restarted. Of course, if a heat exchanger is installed in the suction pipe or a solenoid valve is installed before the expansion valve, it can be improved to a large extent.

When the evaporator is located below the compressor and the suction pipe immediately moves up at the outlet of the evaporator, it is best to set a liquid trap at the turning point so that the liquid does not match the temperature of the thermal expansion valve and only use a thick tube. Switch to a thin tube when it is low. It is possible to install a package contact at the outlet of each ascending pipe to avoid errors in valve control. If the position is limited and the storage bend cannot be set up, the temperature bulb should be placed on the up pipe, and its height above the horizontal section shall not be less than 0.3 to 0.5 meters.

When the evaporator is above the compressor, in order to prevent the refrigerant liquid from sliding into the compressor by gravity when it is stopped, in addition to the liquid trap at the outlet of the evaporator, an inverted u-shaped bend is also provided. However, if A solenoid valve is installed in front of the thermal expansion valve, because the refrigerant in the evaporator is basically evacuated before parking, the refrigerant is not easy to leak after parking, and the suction pipe can go directly down, as shown by the dotted line in the figure .

　　 If an evaporator is composed of several groups, it is best that each group has its own outlet upstream pipe section, which is then connected to the general horizontal suction pipe. Only when it is impossible to achieve such an arrangement, do not use a common upstream tube.

When the suction pipe is connected to the compressor, it should be connected from the compressor. The crankcase pressure flat pipe in this section of the pipeline should have no liquid storage connection between the suction pipe and the compressor to ensure that the return oil can flow back to compression smoothly. The engine will not cause a large amount of oil to suddenly flush back. If several compressors are sucked from a single suction manifold, the arrangement of the branch suction pipes should be as symmetrical as possible so that the amount of oil flowing back to each compressor is as the same as possible.