Page 152 - Pipeline Rules of Thumb Handbook

Hydrostatic Testing 139

If after dewatering, residual moisture in the pipeline poses • The test medium;
a problem, it will be necessary to clean and dry the pipeline. • A description of the facility tested and the test apparatus;
See Section 6 for drying details. • An explanation of any pressure discontinuities, including
A permit to discharge the water may be required, especially test failures, that appear on the pressure record-
if there is a possibility the water may enter a stream of water. ing charts; and,
This should be determined and permits obtained, if required, • Where the elevation differences in the section under test
in the planning phase of the testing operation. A “splash” plate exceed 100 feet, a profile of the pipeline that shows the
or bales of hay may be used when dewatering to prevent elevation and test sites over the entire length of the test
erosion. section.
The most important aspect of any test operation is com-
plete and accurate documentation, since it will become a per- The records required by the Federal Pipeline Safety Reg-
manent record which must be retained for as long as the ulations for pipelines transporting gas are similar to those
facility tested remains in operation. Federal Pipeline Safety required for pipelines used to transport liquids.
Regulations for pipelines transporting liquids require that A typical test report is shown in Figure 8. If failures occur
these records include the following information: during the test, a report documenting the failure and the sus-
pected reasons for the failure should be completed. A typical
• The pressure recording charts; form is shown in Figure 9.
• Test instrument calibration data; A daily operating log should be used to record activities
• The names of the operator, of the person responsible for associated with the test, operating status of the test equip-
making the test, and of the test company used, if any; ment in use, engine rpm’s, and any unusual circumstances
• The date and time of the test; that occur during the test. A typical form is shown in Figure
• The minimum test pressure; 10.

Figure 9. Pipeline failure report. Courtesy Milbar Hydrotest.