Teekay

Can you tell us what the SRV regulator gain and null bias values are, please?

 

Mechanically sound! small term but very important. SRV 77/43=position/pressure. Very important.

Autocal screens in manual are of no use if the valve is not sound. Autocal screens in automatic are completely useless if the valve is not sound.

Check you control spec!!! CSA is trying to help.

http://www.control.com/thread/1026234520#1026235481

Listen and learn. In manual mode, one must change 77/43 in I/O config. Autocal will perform this auto.

Wrong servo ID will destroy your troubleshooting.

 

CuriousOne,

You make some valid points, but this poster is relatively new to Speedtronic control systems. You have thrown out lots of new terms without explaining them sufficiently.

I think when he means "manual" stroking he is referring to using the Manual positioning feature of AutoCalibrate. (That's a guess, but not many sites go through the process of changing regulator types, downloading, rebooting, stroking, verifying, changing regulator types, downloading and rebooting again.) When you mention 77/43, you are talking about the type of regulator being used for the SRV. A type 77 is a pressure control loop with position feedback (high select of two assigned LVDTs). A type 43 is a position control loop with high select of two assigned LVDTs. AutoCalibrate automatically changes the regulator type when using the Manual positioning feature.

We have been trying to tell the original poster that the problem may not be--in fact, probably is not--the Mark V or the servo valve. Valves and actuators do wear over time. They need refurbishment and sometimes outright replacement.

We just have to be patient and hope the original poster will write back with the details of how the problem was resolved.

 

CSA is far better at explaining.

I figure my job is to remind the expert of the simple things that get overlooked or have been discussed in detail before.

CSA works hard!! Sometimes; he just needs to be reminded that one cannot get a complete sequence if the lube oil heater is on!!!

Just respect, nothing else.

 

Like others we are too waiting for the poster to write back about the investigation.

Take care
G.Rajesh

 

Dear all,

our core business is to repair, overhaul and test SRV, GCV, 3way Valve, IGV. act, we are official Y&F workshop.

I'm agree when you wrote, no enough information, and most important no one is mentioning about gas leakage trough the packing ring/ Mark isn't stupid if you have a positive pressure. Mark say go way, stop.
Other causes? so many but like everyone wrote need to read the alarm list, or there is no way to understand the real problem.

I know that the post is old so I don't know if someone of you is still reading this.