[MW:16025] GAS PIPELINE HYDROSTATIC TEST

Dear Experts,

I have 2 question as below:

1- what is the best refrence  for gas pipeline hydrostatic tes procedure.

2-what is the maximum pipeline segment length can we do it and maximum elevation deference in each test segment

The pipeline was:
120km *32inch* 12.7mm thick
And 60km * 24inch
Test pressure 104 bar

FOR ANY EXPLANATION PLEASE GIVE ME THE REFRENCE.
Best Regards