Hydrostatic Test Reference for PVC Required 1

[caneng2002]

I have a design for a potable water system using pvc sched 40 solvent welded pipe.

ASME B31.3 page 104 A345.4.2 reference test pressure of 1.5 times design pressure.

Design pressure is about 100 psi based on the pump supply curve. The downstream distribution system has pressure reducers as required for end user.

A 10" pvc sch 40 max pressure at 73 F is 140 psi (IPEX cat). IPEX may not be using the correct terminology here but I am interpreting max pressure as max sustained pressure and not burst pressure.

1.5 x 100 psi is 150 psi.

My question is I seem to recall but can't find a reference that says I can do a one off hydrostatic test over the max pipe pressure.

Comments appreciated

 

[bimr]

http://www.engineeringtoolbox.com/pvc-cpvc-pipes-pressures-d_796.html

Do a google search for "Georg Fischer 469 Sch80-40 Tech".

In a typical piping standard, the hydrostatic test pressure is 1.5 times the design pressure. See page 70 of the piping standard.

http://engstandards.lanl.gov/esm/pressure_safety/process_piping_guide_R2.pdf

 

[bimr]

140 psi @ 73 F is the maximum operating pressure.

I don't know what your application is, but using 10-Inch PVC sch 40 solvent welded pipe in a water distribution system is not normally recommended.

 

[rconner]

(See history, references and varying opinions etc. expressed in past thread at

http://eng-tips.com/viewthread.cfm?qid=227506)

 

[caneng2002]

Bimr

Thanks for the reference - excellent.

FYI this is mine site in northern Saskatchwan - I said potable but actualy for a process use routed inside a building.

Thanks to everyone.

Closing out this thread.

 

[stanier]

Modern PVC and other thermoplastic standards recommend testing to only 1.25 times the design rating of the material. This is becasue testing at greater than this actually damages the pipe and does nothing to prove the pipe's integrity.

ASME B31.3 is genrally not used for thermoplastics although it does make some reference to non metallics. In Australia the relevant standard is AS 2566.2 for buried pipelines. For above ground piping we have the national plumbing and drainge codes, material standards and the Water Service Association of Austtralia codes. Various authorities use anyone of these standards rather than the pressure piping standard. In the USA you will find AWWA standards are more appropriate for water systems.

You could download the Unibell PVC handbook for mor information.

"Sharing knowledge is the way to immortality"
His Holiness the Dalai Lama.

http://waterhammer.hopout.com.au/