14.2.1 At each
survey, a selected number of steam pipes over 76 mm external diameter
and with bolted joints, are to be removed for internal examination
and are to be hydraulically tested to 1,5 times the working pressure.
If these selected pipes are found satisfactory in all respects, the
remainder need not be tested. So far as practicable, the pipes are
to be selected for examination and hydraulic test in rotation so that
in the course of surveys all sections of the pipeline will be tested.
14.2.2 Where these steam pipes have welded joints between lengths of pipe and/or
between pipes and valves, the lagging in way of the welds is to be removed, the welds
examined, and, if considered necessary by the Surveyor, crack-detected. Pipe ranges
having welded joints are to be hydraulically tested to 1,5 times the working pressure.
Where lengths having ordinary bolted joints are fitted in such pipe ranges and can be
readily disconnected, they are to be removed for internal examination and hydraulically
tested to 1,5 times the working pressure.
14.2.3 At Steam Pipe Surveys specified in Pt 1, Ch 3, 14.1 Frequency of surveys 14.1.1, any copper or copper alloy pipes, such as those
having expansion or other bends, which may be subjected to bending and/or vibration, are
to be annealed before being tested.