5 replies to this topic

[splendid.ye]

Dear Forum members,

 

Currently I have involved in a project and we have centrifugal compressors(integral geared type).

When I look at the whole compressor system, I could find the compressor's suction and discharge shutdown valves operated automatically by logics and those will be closed whenever the coimpressor is tripped at any reason. The thing is this configuration is typical ang general practice and I never had any doubt on this.

However, I recently found that some compressor system hasn't got these shutdown valves(this compressor is also integral geared compressor) and I came to think if these valves are really necessary.

Are those valves are really necessary?

 

What are beneficial of those shutdown valves to the system and compressor itself?

Somethig came into my mind are as following;

1) When there is seal failure, by isolating the compressor system, seal leakage can be minimized.

2) When there is fire, by isolating the system, depressuring can be done and/or feeding the fire can be avoided.

 

Are there any other reasons for the compressor system to have suction and discharge shutdown valves?

 

And importantly, what if we don't have those valves, what kind of adverse impacts on compressor or process system will there be?

 

Thanks in advance.

[fallah]

Hi,

 

Those SDV's are at the compressor suction/discharge lines for easy and fast compressor isolation mostly in emergency cases among which there are two mentioned cases in your post and their necessity is irrelevant to the compressor type...  

 

If they aren't considered where are required due to credibility of one or more emergency case(s), the compressor cannot be easily and quickly isolated and the user/operator should expect to face to catastrophic conditions...

[senthil13]

I would look into the PHA study for this system. the shutdown valves are there for some reasons. 

[Bobby Strain]

Installing automatic isolation valves on the suction and discharge of a compressor is the normal practice. This is where the design should start. Then you can explore why they should be removed. Using this approach your management will not be able to make some foolish decision that compromises the integrity and safety of the operation.

 

Bobby

[sunny143]

SDV's shall be installed on compressor suction & discharge lines (Say 1 complete stage each).

Every client standard clearly depicts the requirement of SDV's on certain conditions. For example, if compressor power is more than 150HP then SDV's shall be provided.

OR

If the compressor process fluid is non combustible or non hazardous fluid then no SDV is required.

 

So, by following the client design philosophy you can go to the final decision about SDV requirement on compressor system.

 

I hope this helps.

 

Regards,

[splendid.ye]

sunny143,

Yes, you are right thanks.

I can just follow client's design specification or philosophy and make final decision easily and I have been doing that all the time.

However, I have always wanted to know the reason why those specification or philosophy are required in the first place and where those came from not just following the specification.   

Edited by splendid.ye, 21 November 2016 - 12:44 AM.