ASME PTB-9:2014 pdf free download – ASME PIPELINE STANDARDS COMPENDIUM
2.5.1.2.1.3 Filling (B31.8- N-3)
Filling is normally done with a high-volume centrifugal pump or pumps. Filling should be continuous and be done behind one or more squeegees or spheres to minimize the amount of air in the line. The progress of flling should be monitored by metering the water pump into the pipeline and calculating the volume of line filled. If necessary, a period of temperature stabilization between the ground and fill water should be provided.
2.5.1.2.1.4 Testing (B31.8- N-4)
(a) Pressure Pump – Normally, a positive displacement reciprocating pump is used for pressurizing the pipeline during test. The flow capacity of the pump should be adequate to provide a reasonable pressurizing rate. The pressure rating of the pump must be higher than the anticipated maximum test pressure.
(b) Test Heads, Piping, and Valves – The design pressure of the test heads and piping and the rated pressure of hoses and valves in the test manifold shall be no less than the anticipated test pressure. All equipment should be inspected prior to the test to determine that it is in satisfactory condition.
(C) Pressuriation – Following is a sequence for pressurization.
(1) Raise the pressure in the section to no more than 80% of anticipated test pressure and hold for a time period to determine that no major leaks exist.
(2) During this time period, monitor the pressure and check the test section for leakage. Repair any major leaks that are found.
(3) After the hold time period, pressurize at a uniform rate to the test pressure. Monitor for deviation from a straight line by use of pressure-volume plots (logs or automatic plotter). (4) When the test pressure is reached and stabilized from pressuring operations, a hold period may commence. During this period, test medium may be added as required to maintain the minimum test pressure.
2.5.1.2.1.5 Determination of Pressure Required to Produce Yielding (B31.8-N-5)
(a) Pressure- Volume Plot Methods – If monitoring deviation from a straight line with graphical plots, an accurate plot of pressure versus the volume of water pumped into the line may be made either by hand or automatic plotter. To make a hand plot, the pump strokes are counted to determine volume and plotted against pressure readings. The plot should be started at a pressure low enough to establish accurately the straight-line portion of the pressure-volume plot. The points should be plotted frequently enough so that deviation from the straight-line portion can be detected readily. The deviation from the straight line is the start of the nonlinear portion of the pressure-volume plot and indicates that the elastic limit of some of the pipe within the section has been reached.
(b) Yield for unidentified or used pipe [as limited by ASME B31.8 para. 841.1 .4(a) and allowed under paras. 811.1(f) and 817.1 .3(h)] is determined by using the pressure at the highest elevation within a test section, at which the number of pump strokes (measured volume) per increment of pressure rise becomes twice the number of pump strokes (measured volume) per increment of pressure rise that was required during the straight-line part of the pressure-volume plot before any deviation occurs.