New gas line – pressure test – how long?

[dave1977]

Hello
My contractor recently installed new gas pipe from new gas meter (external front wall of house) to the kitchen (inside house at back of house – 8m long). The gas pipe is currently in view (waiting for under floor heating to be installed). I wanted the gas pipe tested under pressure (9 bar) before under floor heating is laid.

The contractor got the plumber to insert a device to test the pressure but he only checked the pressure for 2 seconds and then said there is no leak. We said surely it had to be left for longer but he said this is standard practice and only a few seconds is necessary. The gauge did not move from 9bar for 2 seconds. Is 2 seconds sufficient? If not how long should the pressure gauge be left for?

Thanks
Dave

 

[adam84]

Strength tests have no standard test figure requirements, each installation must be calculated individuly this 84mbar figure you offer may be for an air based strength of some description but when testing buy hydrolic means these pressures can be much higher, to test an 8" screwed steel installation with over 70 meters of pipework 84mbar wouldnt show any weakness due to the volume of the pipework.

 

[tamz]

The STP is determined by the MOP or MIP. It has little to do with pipe sizes or volumes. On a std low pressure supply the MIP will be 75mb. STP will be 1.1 x MIP which in this case is 82.5mb. Test duration (for any size pipe) is 5 minutes stabilisation + 5 minutes test. 20% pressure loss is allowable with a pneumatic test and 5% if hydrostatic testing.

On bigger systems at higher pressures (again any size pipe), if the MOP is say 2 bar the STP would be 2bar x 1.5 = 3bar tested for 10 minutes stabilisation plus 5 minute test with the same drops allowed.
Taking it to the extreme with a MOP of 16bar the STP is 16 x 1.5 = 24bar. Hydrostatic test only, stabilise for 30 mins test for 30 mins with a 5% allowable drop.

(IGE/UP1)

 

[stevetheplumber]

Testing a gas pipe thats going to be buried at 20mb is a waste of time flux will hold that sort of presure id give it 3bar and 10 mins for my own peace of mind

 

[Pssst]

This sounds like a case of the blind leading the blind..!!!

Who determined that the test pressure should be 9 bar and on what basis was such a decision made?

What sort of guage was used to measure this test pressure and how was any pressure loss or indeed,rise discerned?

What atmospheric correction employed?

 

[gasmarc]

is this the gas forum lol never heard so much rubbish, 9 bar test dont forget the safety cage

 

[AWheating]

Why would a GSR engineer take the advise of a customer about how and what pressure to test a gas carcus??

where did 9 bar come from?

 

[mountainman]

If it was either eight or twelve bar then I could accept that it's based on The Blues, never tried nine bar tho.
Where's my guitar!

 

[Whn1]

Did he use a foot pump?

 

[glenno1]

As said before in posts a new installation should be tightness tested from meter test point and no drop allowed.Why he tested at extreme pressures is beyond me

 

[mountainman]

I think that this thread was an April Fool windup.
Only two posts from OP now he's disappeared.
(or visiting nine bars)