Volume-II of IV - GAIL

MECON LIMITED
REGD. OFF : RANCHI (BIHAR)
Document3
PROCESS & PIPING
DESIGN SECTION
NEW DELHI
STANDARD SPECIFICATION
TITLE CASING INSULATORS AND END SPECIFICATION NO. PAGE 4 OF 6
SEALS MEC/S/05/62/12 REVISION 0
1.0 SCOPE
2.0 FUNCTION
3.0 DESIGN
4.0 MATERIAL
PART-B CASING END-SEALS
This specification covers the minimum requirements of design, material,
fabrication and supply of casing end-seals intended to be used for pipeline
cased crossings.
Casing end seals are intended to be used for sealing the annular space
between casing pipe and carrier pipe at casing ends so as to prevent ingress
of moisture and water.
The scale shall be suitable for the casing and carrier pipe diameters as
applicable for each case.
The casing end-seal shall be flexible to cater for the expansion and contraction
of carrier and casing pipes and shall be able to tolerate both angular and
concentric misalignment of casing pipe without loss of sealing efficiency.
The design of the casing end-scale shall permit easy installation of the seal to
the cased pipeline crossing.
It shall provide moisture-proof seals when installed for the entire anticipated
life of the buried pipeline.
Manufacturer shall obtain prior approval from COMPANY on casing end seals
design/drawings.
The casing end-scale shall be made of head shrink high density radiation
crosslinked polyethylene with an adhesive having a melt point suitable for the
pipeline service temperature and ambient temperatures foreseen during
construction. End-seals material shall be resistant to heat, cold, vibration,
impact, abrasion, corrosive fluids, disbonding, organic and bio-deterioration.
Manufacturer shall confirm compatibility of end seals with carrier pipe coating.