Volume-II of IV - GAIL

MECON LIMITED
REGD. OFF : RANCHI (BIHAR)
Document6
PROCESS & PIPING
DESIGN SECTION
NEW DELHI
TITLE MAINLINE CONSTRUCTION
(ONSHORE)
STANDARD SPECIFICATION
SPECIFICATION NO. PAGE 15 OF 53
MEC/S/05/62/01 REVISION A
Use of vaccum lifting equipments are preferred. Hooks may also be used for
handling the pipes provided they have sufficient width and depth to fit the inside
of the pipe and covered with soft material like rubber, teflon or equivalent, so as
not to cause damages to bevel or pipe ends. During hoisting, cables/wire ropes
shall have sufficient inclination compared to pipe axis so that they do not come
into contact with external coating.
Coated pipes may be handled by means of slings and belts of proper width
(minimum 60mm) made of non-metallic/non - abrasive materials. In this case,
pipes to be stacked shall be separated row by row to avoid damage by rubbing
the coated surface in the process of taking off the slings. Use of round sectional
slings are prohibited.
During handling, suitable handling equipment with proper length of booms shall
be used. Fork lifts may be used provided that the arms of the fork lift are
covered by suitable pads preferably rubber. Before lifting operations it is
essential to ensure that the pipe surface is free from foreign material with sharp
edges. Belts/slings when used shall be cleaned to remove hard materials such
as stone, gravel etc. Coated pipes shall not be bumped against any other pipe
or any other objects. Rolling, skiding or dragging shall be strictly forbidden.
Coated pipes at all times shall be stacked completely clear from the ground so
that the bottom row of pipes remain free from any surface water. The pipes shall
stacked at a slope so that driving rain does not collect inside the pipe.
The coated pipes at all times shall be stacked by placing them on ridges of sand
free from stones and covered with a plastic film or on wooden supports provided
with suitable cover. This cover can, for example, consist of dry, germ free straw
with a plastic film, otherwise foam rubber may be used. The supports shall be
spaced in such a manner so as to avoid permanent bending of the pipes,
particularly in case of small diameter pipes with low wall thickness. The pipes
shall be stacked so that the uncoated bevelled ends are in line at one end thus
making differences in length clearly noticeable.
Stacks shall consist of limited number of layers so that the pressure exercised
by the pipe's own weight does not cause damages to the coating. Each pipe
section shall be separated by means of spacers suitably spaced for this
purpose. Stacks shall be suitably secured against falling down and shall consist
of pipe sections having the same diameter and wall thickness. The weld bead of
pipes shall be positioned in such a manner so as not to touch the adjacent
pipes.