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Re: [MW:15823] HST Pressure variation in two pressure gauges

By Materials & Welding
Dear Dasari,

1. Yes there will be variation in pressure gauge reading when they are fitted at different heights because of the general static head difference, Generally for 10 meter static head difference the pressure difference will be 1 bar (14.5 psi).

2. Normally the first step can be 50% the test pressure and then pressure can be increased to the final test pressure by another 5 steps each compensating 10% totaling 100% by 6 steps.

 3. I think socket weld is a circumferential weld as it makes a complete circumference.

On Wed, Oct 31, 2012 at 10:03 AM, srikanth dasari <dasarosyis@gmail.com> wrote:
Dear experts,

1.while performing a Hydro static test in a pipe line/spool at two different elevation for a continuous one line ,one pressure gauge  has found one reading  at one elevation and another pressure gauge has found another reading at another elevation how much can be the pressure variation in the Two pressure gauges as temperature is also a factor how much temp variation can be allowed as per code???

2.How much percentage of  increase in testing pressure can be increased in testing a pipe line for HST for a specific Testing pressure given in the Drawings???  

3.Please clarify whether Socket weld is Circumferential welding or not define types of circumferential joints???


DASARI SRIKANTH

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Thanks & Regards
Srirammadhan
Piping/painting inspector
Great drill Chaaya
Great Ship
Hamriyah Free zone, UAE


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