在自动控制的制冷系统回汽管路上,经常采用的控制阀门有 ZCL—□□QB 常闭型电磁主阀、ZCL—□□QK 常开型电磁主阀、两个 ZCL—3与 ZFS—□□QB 组成的双电磁主阀等。这些阀门可根据制冷系统的具体情况来分别选用。1.ZCL—□□QB 常闭型电磁主阀。它在回汽管路上的连接如图1所示。该阀在它的进、出口有一定的压差时,便能开启。一般微开压差为0.07kg/cm~2,全开压差为 In the automatic control of the refrigeration system back to the steam line, the control valve often used are ZCL- □ □ QB normally closed solenoid valve, ZCL- □ QK normally open solenoid valve, two ZCL-3 and ZFS- □ □ QB consisting of dual electromagnetic valve and so on. These valves can be selected according to the specific circumstances of the refrigeration system. 1.ZCL- □□ QB normally closed solenoid valve. Its connection to the steam return line is shown in Figure 1. The valve in its import and export of a certain pressure, they can open. The general micro-open pressure is 0.07kg / cm ~ 2, full pressure is