Electromagnetic valve control logic for dry gas seals!

The first condition should be that the pressure difference between the inlet and outlet of the circulation pump is below 0.15 MPa; in such a case, it can be determined that the circulation pump has stopped operating. It is necessary to open the solenoid valve connecting the outlet of the new hydrogen pump to the dry gas seal. However, I’m not sure what SRQ means in the box below!

Dry gas sealing is a type of mechanical seal that is commonly used in rotating equipment such as pumps and compressors, especially in situations where flammable, explosive, or toxic media are handled. Dry gas seals in diesel hydrogenation units are typically used to protect the compressors and ensure that hydrogen does not leak into the environment. Solenoids are used in the control logic to regulate the flow of sealing gas (such as nitrogen or clean process gas). The control logic diagram of a dry gas seal typically includes the following main components: 1. **Pressure and flow control**: Solenoid valves are used to adjust the pressure and flow rate of the sealing gas in the dry gas seal system. Under normal operation, the solenoid valve maintains the set pressure and flow rate to preserve the sealing effect. If abnormal pressure or flow is detected, the control system will adjust the opening degree of the solenoid valve or completely shut it off to prevent further damage. 2. **Safety protection**: If the system detects abnormal pressure or excessively high temperature at the gas side of the compressor, the solenoid valve can be quickly closed to cut off the supply of sealing gas and prevent gas leakage. At the same time, a backup system may also be activated to stabilize the operation of the device. 3. **Interlock logic**: To ensure the safe operation of the system, the sealing system may be interlocked with other protection systems of the compressor (such as emergency stop buttons, pressure or temperature overload protection). This means that when these systems send out warning signals, the solenoid valves may automatically carry out the corresponding actions. 4. **Monitoring and Alarm**: The control logic should also include sensors for monitoring the sealing condition; once a leak, pressure drop, or other abnormal condition is detected, the system should immediately issue an alarm signal and take appropriate protective measures using actuators such as solenoid valves. When interpreting a control logic diagram, it is necessary to pay attention to the devices represented by various symbols in the diagram and the connections between them. Lines generally represent the path of signal or gas flow, while symbols denote control elements such as sensors, controllers, solenoid valves, etc. In the logic diagram, it shows how these components interact with each other and how they should respond under various conditions. To understand in detail the control logic of a specific device, its control logic diagram along with relevant technical manuals or instructions are needed, so as to more accurately comprehend its working principle and control strategies. .