Valve insulation

[Valving]

Is there any norm to describe when valve insulation shall be made?
There is a pipeline for 40-50 deg. C operation and steam is purged for 24 hours
once a year at 400 deg & 10 bars.
Do you see any necessity to apply insulation for a butterfly valve?

 

[LittleInch]

whatever applies to the piping should apply to the valve.

If you can successfully barrier off the line then you could do it without insulation, but you will need to be careful with that temperature.

My issue would be what one day at 400C is doing to your valve and stem seals....

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

 

[gerhardl]

As LittleInch (he is straight to the point again!) I am more conserned about the valves ability to withstand the temperature (is the valve really constructed and certified for this temperature?) than the necessity of insulation. The 400 degrees gives a vastly overheated steam at this pressure, which again rises the question of the actual control of pressure: is it sure that the pressure will be within 10 bar, and can (again) the valve, in case, withstand a higher pressure at this temperature?

To the question: Insulation of steam valves is relatively cheap, and can for instance be obtained by tailored 'stuffed' jackets, fastened by bands to the valves. The insulation will both protect operators against accidental burns and guard against (some amount) of heat loss.

For 24 four hours purging at higher temperature it also might help protect aganst temperature fluctations, depending on required accuracy and surrounding temperature and variation. Regarding the cost of heat-loss insulation will probably (depending on cost of heat source) count less.

(General questions will give general answers: good luck!)