Issues regarding the insulation and corrosion protection of water supply pipes~
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According to GB50268-2008, for pressurized pipelines undergoing hydraulic testing, the testing is required to be carried out after the pipes are covered with soil. If insulation is needed for the pipelines, is it necessary to wait until the testing is successful before removing the soil layer in order to apply insulation or anti-corrosion measures? How is it constructed in actual projects? Thank you~
It’s unlikely that this will be done; the standard procedure is: pressure testing – anti-corrosion treatment – insulation – backfilling. Before pressure testing, anti-corrosion and insulation treatments should be carried out first, except at the weld areas (I have no experience in installing insulated pipes buried underground; this is just my personal understanding for reference only)
During construction, soil is generally not laid on top; first, pressure testing is carried out, then insulation is applied, and finally soil is placed on top
Thank you. Do you mean that the pressure test and tightness test are merely to check the quality of the welds and joints on the vehicle?
Thank you. Do you mean that the pressure test and tightness test are merely to check the quality of the welds and joints on the vehicle?
The soil covering around pressurized pipes is, in theory, also part of what exerts pressure on the pipes; that’s why the standards specify that the soil cover should extend 500 millimeters above the top of the pipes
It should be done properly like this, but many do it for convenience’s sake. . . There are also costs and time
If the goal is merely to test the sealing performance and pressure resistance of the pipeline at the welded joint, then this problem wouldn’t arise. However, I believe that pressure testing and integrity testing are meant to assess the entire pipeline. If that’s the case, is the correct sequence of operations to first cover the pipeline with soil for pressure testing, and then dig it back up again to insulate it?
In ultra-high-pressure pipelines, if the pipes are not buried, they are prone to moving or posing a danger. Since the construction sites I have worked on do not have ultra-high-pressure pipelines, and things are handled there for convenience as you mentioned, the construction standards still provide detailed instructions regarding the methods of pressure testing. What I want to know now is whether my understanding as stated in my title is correct I wanted to include this part during settlement, but based on past experience, no one mentioned it. It’s not mentioned either in the construction organization design.
I have carried out construction work on such anti-corrosion and insulation projects