The effect of the pipe diameter of the automatic control valve on suction force
Thread Content
The diameter of the automatic control valve for hydrogen reflux in our section used to be 65 mm in nominal diameter. The PID settings on the real-time monitoring screen on the computer were P–79.99%, I–0.40, and D–0. Some time ago, we replaced it with a smaller automatic control valve with a nominal diameter of 50 mm; since then, the monitoring curve on the computer has become very unstable, which affects the suction force of hydrogen. What I want to ask is: how should the PID parameters be adjusted when the diameter decreases?
The diameter of a control valve is related to its flow coefficient; if calculations show that the flow capacity of a DN50 valve meets the process requirements, instability in the curve may be due to issues in the process operation or improper tuning of the PID parameters. There are many methods for PID tuning on forums. For example: [Daily Question 20090219] Briefly describe the steps for tuning PID parameters using the trial and error method. http://bbs.hcbbs.com/viewthread.php?tid=393474&page=1#pid2098339
After the selection of the control valve is changed, the operation of the process will certainly be affected; accordingly, the PID tuning of the instruments also needs to be adjusted in order to achieve stable operation.
The diameter of a control valve is related to its flow coefficient; if calculations show that the flow capacity of a DN50 valve meets the process requirements, instability in the curve may be due to issues in the process operation or improper tuning of the PID parameters. There are many methods for PID tuning on forums. Take a look for yourself – the process needs to be adjusted gradually, and your feedback is needed to verify it: handshake