Volume-II of IV - GAIL

MECON LIMITED
REGD. OFF : RANCHI (BIHAR)
c:\fateh\standard\stad-eqp.wp
PROCESS & PIPING
DESIGN SECTION
NEW DELHI
STANDARD SPECIFICATION
TITLE Hydrostatic Testing of Onshore Cross- SPECIFICATION NO. PAGE 10 OF 17
country Pipelines
MEC/S/05/62/03 REVISION A
Bleed-off water shall be accurately measured and recorded.
8.0 ACCEPTANCE
8.1 The hydrostatic test shall be considered as passed if pressure has kept a constant
value throughout the test duration, except for change due to temperature effects. Such
change shall be evaluated as described under clause 12.2 of this specification.
The pressure change value as a function of temperature change shall be algebraically
added to the pressure value as read on the meters. The pressure value thus adjusted
shall be compared with the initial value and the test shall be considered as acceptable
if the difference is less than or equal to 0.3 bar. In case of doubt the testing period shall
be extended by 24 hours.
8.2 If test section fails to maintain the specified test pressure after isolation,
CONTRACTOR shall determine by search the location of leakage or failure. All leaks
and failures within the pipe wall or weld seam shall be repaired by replacement of entire
joint or joints in which leakage or failure occurs. In circumferential welds the method of
repair shall be determined by the COMPANY. CONTRACTOR shall comply with
instructions of the COMPANY whether to replace a section of the line pipe that
includes the line leak or whether to repair the circumferential weld. This repair should
however meet the requirements of 'Specification for Welding Pipelines and Related
Facilities'. Where failure occur in pipeline field bends, bends shall be replaced with
same degree of bends. After completion of repairs, the hydrostatic test shall be
repeated in full, as per this specification.
8.3 The cost of repairs or replacements, followed by refilling and repressurizing the line,
due to poor workmanship, shall be borne by the CONTRACTOR. In the event of leaks
or failures resulting form faulty COMPANY furnished materials, CONTRACTOR shall
be reimbursed for furnishing all labour, equipment, materials, except those materials
furnished by the COMPANY, and transportation necessary to repair and repressurize
the section of the pipeline to the pressure at the time of recognition of leak or line
failure. CONTRACTOR shall be entitled for compensation as per the provisions of the
CONTRACT. All work of reinstalling line pipe, to replace pipe failures shall be done in
accordance with the relevant specification included in the CONTRACT.