PRESSURE VESSEL DESIGN FOR SAFETY VALVES TESTING 4

[skengg]

hello to all,
this is actually my first post in pressure vessel forum. i am actually a valves design engineer. our company wants to design a pressure vessel for safety valves testing(setting/adjusting desired pressure on steam flow). the pressure vessel will be connected to boiler through pipe line for regular steam supply. all i have data of Max. allowable working pressure(let's say 20 kg/cm2) and steam storage capacity(let's say 31000 kg/hr.) of pressure vessel.
i am newbie in pressure vessel design, can anybody of you recommend some literature or ASME section VIII specific code which i need to follow for vessel thickness design and other consideration. let me clear that it's only inhouse development for our safety valves testing so no need to focus much on ASME STAMPING and other standard consideration. all we need sustainable design which can hold pressure and fulfill our task.

 

[mk3223]

Is it to design and test the pressure vessel or use the vessel to test the safety valve?

IMO, you may design the pressure vessel and follow the ASME Code VIII-1 for the in-house use. It may have adequate safety factor as needed for the operation even without a stamp.

 

[skengg]

It's actually design of pressure vessel for safety valves testing. we dont work in pressure vessel industry. its just we need a vessel for safety valves testing so we can test it on steam supplied by boiler to the vessel. can you suggest specifically what clause in ASME section VIII deal with vessel cylinder design otherwise i have to read whole ASME section VIII code book.
thanks.

 

[JStephen]

The specific code to be used may be mandated by government codes (typical in US and many other places).
Note that kg/hr is a mass flow rate, not a storage capacity, so we don't have a clue what size vessel you're dealing with.
If it's a vessel of any size that holds pressurized steam, I would highly recommend that you just buy the finished vessel and have the detailed design done by a reputable supplier per ASME or other codes.
Design of a cylinder for pressure is pretty simple and straightforward, but the bulk of the code rules deal with the details, not that particular aspect of design.

 

[skengg]

Thanks. i also think that buying finished vessel from supplier as well as giving them input requirement sheet so they calculated all parameters and manufacture according to it.

 

[GD2]

Skengg,
Just a curiosity. Why your company wants to test the PRVs on steam? Don’t have other PRVs in your plant other than on steam service?
Depending on your steam condition, you might have to insulate the test rig and also have more maintenance problems on steam service.
What’s the justification your company don’t want to test the PRVs on air?

GDD
Canada

 

[skengg]

GD2,it's actually due to some operating issue, we getting a lot of complaints regarding safety valve not working correctly in line services. most of them out of these are tested ok in air testing but still somehow getting problems in operation.

 

[LittleInch]

It's actually design of pressure vessel for safety valves testing. We don't work in pressure vessel industry. its just we need a vessel for safety valves testing so we can test it on steam supplied by boiler to the vessel.

skengg, You don't actually seem to understand how dangerous this is. You can't just read part of ASME VIII and think you can design a pressure vessel. Nearly every country has rules and regulations for design, fabrication and inspection of pressure vessels to protect workers and members of the public. I don't know what India has, but there do seem to be regulations.

https://www.ndt.net/article/nde-india2016/papers/A316.pdf

Even if for some reason this one is too small or not high enough pressure, it still doesn't mean you should be doing this. If you're working next to it then you are in danger, if not, your fellow workers are in danger, but if this vessel failed then you become responsible and could easily be jailed.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[skengg]

LittleInch, i understand this that's why we quote our requirements to our vendors so that they can supply pressure vessel as per standard. initially, we thought to calculate & ddesign by our self but as we are not vessel manufacturing company, so it's not good idea. thanks for your concern

 

[LittleInch]

Thank you for responding in a responsible manner.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.