The selection and matching of thermal shrinkage valve plays an important role in the performance of the whole air compressor working system. Correct selection of thermal shrinkage valve will maximize the daily use of evaporator, and make the evaporator always match the heat load.
Phenomenon of mismatch between thermal shrinkage valve and system当发作不匹配时，系统的制冷剂流量将或多或少，这将招致热收缩阀制冷才能忽大忽小的情况。
When a mismatch occurs, the refrigerant flow rate of the system will be more or less, which will lead to the condition that the refrigeration capacity of the heat shrinkage valve will be neglected.
1. When the opening of the thermosystolic valve is too small, there will be a shortage of refrigerant supply, and there will not be enough refrigerant to evaporate in the evaporator, so that the refrigerant can evaporate in the way of moving in the evaporator tube. Thereafter, there is no liquid refrigerant evaporation in the evaporator pipeline as long as the steam is overheated. As a result, a considerable number of evaporators fail to give full play to their efficiency, resulting in a lack of refrigeration capacity, slowing down the cooling rate and reducing the cooling effect of air conditioning, which will have a negative impact on system performance.
2. If the opening of the thermosystolic valve is too large, that is, the amount of liquid supplied by the thermosystolic valve to the evaporator is larger than the load of the evaporator, some liquid refrigerants will evaporate in the evaporator and enter the compressor together with the gaseous refrigerant, which will cause the liquid hammer (wet stroke), and even the cylinder impact accident, and damage the compressor. In addition, when the refrigeration capacity is too large, it will cause oscillation, intermittently supplying excessive liquid to the evaporator, resulting in sharp fluctuation of the suction pressure of the compressor. At the same time, the opening of the thermal shrinkage valve is too large, which increases the evaporation temperature, reduces the refrigeration capacity, increases the power consumption of the compressor, and increases the power consumption.
Understanding how to choose thermal shrinkage valve关于热力收缩阀的选择我们需求依据制冷系统的制冷剂品种、蒸发温度范围和蒸发器过热负荷的大小来停止参考判别。以下几点是选择时需求肯定的：
As for the choice of thermal shrinkage valve, we need to stop the reference judgment according to the refrigerant type of refrigeration system, the range of evaporation temperature and the size of the evaporator superheat load. The following points are certain when choosing:
1. Pressure drop of positive valve.
冷凝压力和蒸发压力之间的差值。 经过从该差值中减去一切其他压力损失来取得阀的净压降。 但是，应思索一切可能的压降源：（1）流经包括冷凝器和蒸发器在内的制冷剂管道时的摩擦损失，（2）流过液体管道配件（如电磁阀和过枯燥器）时的压降，（3）静电 液体管垂直提升（降落）惹起的压降（上升），和（4）经过制冷剂分配器（假如运用分配器）时的压降。
The difference between condensation pressure and evaporation pressure. The net pressure drop of the valve is obtained by subtracting all other pressure losses from the difference. However, all possible sources of pressure drop should be considered: (1) friction loss when flowing through refrigerant pipes including condensers and evaporators; (2) pressure drop when flowing through liquid piping fittings (such as solenoid valves and dryers); (3) pressure drop caused by vertical lifting (falling) of electrostatic liquid pipes; (4) pressure drop caused by passing through refrigerant distributors (if using distributors) Pressure drop at time.
2. Select the valve from the refrigeration capacity reference table of each valve series.
依据设计的蒸发温度和可用阀门的压降，假如可能，阀门的制冷量应等于或略大于设计等级。 系统。 关于具有多个蒸发器的系统，应依据每个蒸发器的制冷才能选择每个阀门。
According to the designed evaporation temperature and the pressure drop of the available valve, if possible, the refrigeration capacity of the valve should be equal to or slightly greater than the design grade. System. For systems with multiple evaporators, each valve should be selected according to the refrigeration of each evaporator.
3. To confirm the refrigerant type of the system.
4. Define the evaporation temperature range of evaporator.
5. Affirming whether external equilibrium tube can be needed.
The pressure drop between the outlet of the valve and the part where the thermostat is located will determine whether the external balancing pipe can be required.
6. Refrigeration capacity.
7. Pressure difference between inlet and outlet of thermosystolic valve.
8. Internal or external pressure balance.