The expansion valve is an important accessory in the high and low temperature integrated machine. The manufacturer tells you that there are various kinds of expansion valves, and different expansion valves have different differences.
The high and low temperature integrated machine expansion valve mainly has two kinds of thermal expansion valve and electronic expansion valve. Generally speaking, the electronic valve is used more. According to the driving method, it is divided into electromagnetic type and electric type. The electromagnetic type electronic expansion valve is attracted by electromagnetic force. The coil, the plunger (moving iron core), the valve needle, the valve seat, the reaction force spring, etc., the driving force of the electric electronic expansion valve is a motor, which is divided into a direct motion type and a speed reduction type.
Compared with the original thermal expansion valve, the advantages of the electronic expansion valve are quite numerous. The flow regulation is not affected by the change of the condensing pressure; it compensates for the change of the subcooling degree of the refrigerant before the expansion valve; because the electric signal is transmitted quickly, the execution action is rapid and accurate, so the flow can be adjusted accurately and timely, even if the change is severe, It can also avoid oscillation; it can control the evaporator outlet superheat to a small extent, thereby greatly improving the utilization of the heat transfer area of the evaporator; the same superheat setting can be set in the entire operating temperature range of the freezer. The value can be adjusted according to the actual condition of the freezer. It is not limited to the proportional adjustment. It can also use proportional integral or other adjustment rules, and can adjust the adjustment parameters.
The choice of different types of high and low temperature integrated machines in the manufacturer is somewhat different on the expansion valve. It is also very important for the cooling and heating effect. You should pay attention to its performance and quality.