Protection of pressure vessels in hot, sunny
Protection of pressure vessels in hot, sunny
(OP)
Dear all
I have to provide some pressure vessels, containing unheated water at up to 20 BarG, for use in Saudi Arabia on a pumping station.
The vessels are located outdoors and our client has suggested that we need to protect the vessels against the sun.
Has anyone experience of these type of environement and what is the usual practice, my experience is in the UK where we don't have much sun (I know what to do about rain !!).
Is this really a problem, can't I get away with a suitable UV resistant paint ?
Thanks for any help
Max
I have to provide some pressure vessels, containing unheated water at up to 20 BarG, for use in Saudi Arabia on a pumping station.
The vessels are located outdoors and our client has suggested that we need to protect the vessels against the sun.
Has anyone experience of these type of environement and what is the usual practice, my experience is in the UK where we don't have much sun (I know what to do about rain !!).
Is this really a problem, can't I get away with a suitable UV resistant paint ?
Thanks for any help
Max





RE: Protection of pressure vessels in hot, sunny
I have seen pictures of oil storage tanks in Saudi (you can actually google earth it), and it seems like they are just metal tanks painted white, much like anywhere else.
Is there anything specific about your cold water tank?
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RE: Protection of pressure vessels in hot, sunny
I'm assuming you've designed the tanks so that thermal expansion is not an issue.
RE: Protection of pressure vessels in hot, sunny
So---do you have any attachments or controls? The surface temprature of the vessel may get hot enough to literally fry an egg on.
At least you don't need to worry about rust. The only thing that does not need protection from the sun is the sand.
RE: Protection of pressure vessels in hot, sunny
Re: Instruments and attachments
We are supposed to provide level and pressure gauges and spring loaded pressure relief valves. There will be some instrumentation cabling - I guess we can shade this from direct sunlight by careful design.
Re: Duty
The tanks are to be provided for surge protection on the pumping station discharge lines, so they wil just sit there half full of water, half full of air, and remain at ambient temperature.
Our client has no specific requirements for protection other than the wonderful standard "Vendor proposal" so I guess we only need to be responsible in what we propose.
RE: Protection of pressure vessels in hot, sunny
Look under "Breaking News" for some applications.
http://www.eaglecoatings.net/
RE: Protection of pressure vessels in hot, sunny
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdo/
RE: Protection of pressure vessels in hot, sunny
We haven't been specified a site temperature, not a helpful client, so I guess we are left with the possibility that if we leave the tank exposed we might get a surface temperature of anything up to 150-200 Deg F (egg frying temperatures).
I would think the air temperatures will quite happily get to over 100 F.
Max
RE: Protection of pressure vessels in hot, sunny
As much as the tank and content may get hot during the day time, at night that same system and content will cool down probably just as much since night time temperatures will drop significantly and you would experience a significant radiation cooling. I would look at the same paint system used on propane bulk storage tanks if your client agrees to a paint system. Also if it is convenient look at similar installations in the region.
RE: Protection of pressure vessels in hot, sunny
Geoffrey D Stone FIMechE C.Eng;FIEust CP Eng
www.waterhammer.bigblog.com.au
RE: Protection of pressure vessels in hot, sunny
a) if the tank is left isolated with no significant influent or effluent, then the thermal expansion of the liquid can lead to tank failure unless an adequately sized relief valve is provided. This means determining max rate of heat absorption and max rate of d(rho)/dT for liquid water. An inlet check valve may effectively cause tank isolation during periods of no flow.
b) unless there is an inlet check valve , then swelling of teh water can lead to backflow to the upstream system, and there may be some cases where that is not permitted.
c) To avoid having to drain teh tank in order to maintain a leaking relief valev, you may want to mount 2 relief valves downstream of a 3-way block valve.
RE: Protection of pressure vessels in hot, sunny
Steve Jones
Materials & Corrosion Engineer
http://www.pdo.co.om/pdo/
RE: Protection of pressure vessels in hot, sunny
I see lot of good answers to your question, but it appears everyone is just making assumption on what the question is. Simple answer to your question is, when in doubt, ask your client in writing to get a clear specification on what he wants. Your client will be very mad if you assume and not be able to meet what he had in mind. Remember what Benny Hill says about "assume"?
RE: Protection of pressure vessels in hot, sunny
Yes I do remember Benny Hill.
Your help is appreciated.
Max