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LARSEN & TOUBRO LIMITEDPAGE NO.- 1 OF 19
DATE:-01.11.2007MSQ (EPCC-1) UPGADATION PROJECT REV.NO.- 0
PROCEDURE FOR AG PIPING FABRICATION & ERECTION
PROCEDURE NO.-LT/MSQ/P/AG/005
CONTENTS
1.0 PURPOSE
2.0 SCOPE
3.1 STANDARD SPECIFICATIONS &
NORMAL PRACTICE
3.2 DEVIATION
4.0 FABRICATION
5.0 ERECTION
6.0 PERFORMANCE OF WELDS & HEAT TREATMENT
7.0 WELDING CONSUMBALES
8.0 SHIELDING & PURGING GAS
9.0 WELDING
10.0 VISUAL INSPECTION
11.0 REPAIRS OR REMOVAL OF DEFECT
12.0 INSPECTION AND TESTING
13.0 SAFETY
14.0 DOCUMENTATION
APPROVED BY L & T REVIEWED / APPROVED BY JACOBS
LARSEN & TOUBRO LIMITEDPAGE NO.- 2 OF 19
DATE:-01.11.2007MSQ (EPCC-1) UPGADATION PROJECT REV.NO.- 0
PROCEDURE FOR AG PIPING FABRICATION & ERECTION
PROCEDURE NO.-LT/MSQ/P/AG/005
1.0 PURPOSE:
The purpose of this procedure is intended to cover the general requirements
for the execution of piping, pre-fabrication, assembly and erection of the
above ground pipe work at site.
2.0 SCOPE:
This procedure covers execution, inspection, testing, and method of record
keeping for fabrication & erection of all above ground piping systems as per
standard specification and normal practice.
3.1 CONTROLLING SPECIFICATIONS:
● Approved PMC’s standards and specifications• Process and instrument diagram.
• Piping materials specification
• Pipe supports standards
• Line list.
• Job specification of non-destructive testing of piping as per Sec V &
standard spec
• Welding specification for Fabrication of piping (3177-LSS-104)
• Standard specification for Inspection, flushing piping system (3177-
LSS-106)
• Specification for inspection, flushing & testing of piping
systems(3177-LSS-106)
• ASME B 31.3 Process Piping
• AME B 31.1 Power Piping
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DATE:-01.11.2007MSQ (EPCC-1) UPGADATION PROJECT REV.NO.- 0
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• ASME Sec VIII code for Unfired Pressure Vessel
• IBR Regulations
• IS : 823 code for Procedure for Manual Metal Are Welding of Mild
Steel ( For Structural Steel)
• Job specification for colour coding
3.2 DEVIATIONS
Where a deviation from the “Basis of work” and approved job procedure
described above is required or where the basis of work does not cover a
particular situation, the matter shall be brought to the notice of owner / PMC
and work carried out only after obtaining written approval from him in each
cases.
4.0 FABRICATION:
4.1 PIPING MATERIAL
Pipe, pipefitting, flanges, valves, gaskets, studs bolts etc. used in a given
piping system shall be strictly as per the “Piping Material Specification” for
the “Pipe Class” specified for that system.
For the purpose of common understanding the construction job procedure, to
be submitted by L&T , shall include proposal for
-Maximizing prefabrication, inspection and testing at fabrication shop with
minimum field joints
-Positive material identification, handling, storage & preservation.
4.2 DIMENSIONAL TOLERANCES
Dimensional tolerances for piping fabrication shall be as per standard no.
3177-LSD-1017. To take care of minor variations in the actual location (at
site) of equipments, inserts, structures etc., field welds shall be provided
during piping fabrication and an extra length 100 mm & above the dimensions
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PROCEDURE NO.-LT/MSQ/P/AG/005
indicated in the drawing may be left on one side of the pipe at each field
welds.
4.3 IBR PIPING
The complete piping work shall be carried out as per Approved for
Construction drawings and sketches. For piping falling under IBR, necessary
approval of boiler inspector on the drawings shall be obtained prior to start of
fabrication and all works shall be carried out as per the requirement of IBR.
IBR approval to be taken on as built IBR Drg.
Field welding of weld joint nearest the pumps shall be done only after
pump and connected piping have been truly aligned.
4.4 EDGE PREPARATION
4.4.1 The edges to be welded shall be prepared to meet the joint design requirements by
any of the following method recommended:
a) Carbon Steel (C.S.)
Gas cutting, Machining or grinding methods shall be used. After gas
cutting, oxides shall be smoothened / removed by chipping and grinding.
b) Low Alloy Steel (Containing up to 5% Cr)
Gas cutting, Machining or grinding methods shall be used. After gas
cutting, machining or grinding shall be carried out on the cut surface.
c) High Alloy Steel (>5% Cr) & Stainless Steels (S.S), Nickel Alloys
Plasma cutting, machining or grinding methods shall be used. After plasma
cutting, cut surface shall be machined or ground smooth.
4.4.2 SPACING
)a For pipe wall thickness 5 mm and above, the ends to be welded shall secure
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in position with the aid of couplers, yokes and ‘C’ clamps, to maintain
perfect alignment. Yokes shall be detached after the completion of weld,
without causing any surface irregularity.
)b Tacks should be equally spaced. Minimum number of tacks shall be:
3 tacks - for 21/2” and smaller diameter pipes
4 tacks - for 3” to 12” diameter pipes
6 tacks - for 14” and larger diameter pipes
4.4.3 All piping spools shall be marked / stamped for proper identification like as line no.,
joints no., welder no., spool no.
4.4.4 CLEANING
)a The ends to be welded shall be properly cleaned to remove paint, oil,
grease, rust, oxides, sand, earth and other foreign matter. The ends shall be
completely dry before the welding.
)b On completion of each run, craters, welding irregularities, slag etc., shall be
removed by the grinding and chiselling. Separate grinding wheels and wire
brushes should be used for Carbon steels & stainless Steel
4.5 PIPE JOINTS
The piping class of each line specifies the type of pipe joints to be adopted. In
general, joining of line 2’’ and above in process and utility piping shall be
accomplished by butt weld. Joining of lines 11/2” and below shall be by socket
welding / butt welding / thread joints as specified in “Piping Material
Specification”.
Flange joints shall be used at connections to vessels, equipments, valves and
where required ease of erection and maintenance as indicated in drawings.
4.6 BUTT WELDED AND SOCKET WELDED PIPING
Edge preparation, alignment and fit up of piece to be welded, welding, pre
heating, post heating and heat treatment shall be as described in the welding
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specification (3177-LSS-104) and NDT specification (18-3177-000-L-02-
0703-A4).
4.7 SCREWED PIPING
In general, galvanized piping shall have threads as per IS: 554 or ANSI B 2.1
NPT as required matching threads on fittings, valves etc. all other piping shall
have threads as per ANSI B 2.1, tapered unless specified otherwise.
4.8 FLANGE CONNETIONS
All range facings shall be true and perpendicular to the axis of pipe to which
they are attached. Flanged bolthholes shall straddle the normal centre lines
unless different orientation is shown in drawing.
4.9 BRANCH CONNECTIONS
Branch connections shall be as indicated in the Piping Material Specifications
for end preparation, alignment; spacing, fit up and welding of branch
connections refer welding specifications. Templates shall be used wherever
required to ensure accurate cutting and proper fit up.
Reinforcement pads shall be provided wherever indicated in drawings /
specifications / standard and codes etc.
4.10 BENDING
Bending of pipe shall be done as per ASME B31.3. Cold bend for lines 1½
and below, with a bend radius of 5 times the nominal diameter shall be used
as required in place of elbows wherever allowed by piping specifications.
Bending of pipes 2” and above may be required in some cases like that for
headers, reactors etc.The competed bend shall have a smooth surface, free
from cracks, buckles, wrinkles, bulges, flat spot and other serious defect.
4.11 FORGING AND FORMING
Forging and forming of small bore fittings like reducing for piping 1½” and
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below, shall be as per ASME B 31.3 / ASME B 31.1.
4.12 MITRE BENDS AND FABRICATED REDUCERS
Mitre bends and fabricated reducers shall be governed by the piping material
specifications. Generally all 90º mitres shall be 4-piece 3-weld types and 45º
mitres shall be 3-piece 2-weld types unless otherwise specified. Reducers
shall be fabricated as per directions of the PMC.The radiographic
requirements shall be as per Material Specifications for process and utility
systems and NDT specification for steam piping under IBR, radiographic
requirement of IBR shall complied with.
4.13 CUTTING AND TRIMMING OF STANDARD FITTINGS & PIPES
Component likes pipes, elbows, couplings, half couplings etc shall be trimmed
/ edge prepared wherever required to meet fabrication and erection
requirements, as per drawings and instructions of owner / PMC.
4.14 GALVANISED PIPING
Galvanised carbon steel piping shall be completely cold worked, so as not to
damage galvanised surface. This piping involves only threaded joints and
additional external threading on pipes may be required to be done as per
requirement. However threading after galvanising should be minimum.
4.15 JACKETED PIPING
The jacking shall be done in accordance with approved PMC’s or licensors
approved specification as suggested in Piping Material Specification. Position
of jump over and nozzles on the Jacket pipes, fittings etc. shall be marked
according to pipe disposition and those shall be prefabricated to avoid
damaging of inner pipe and obstruction of Jacket space.
4.16 SHOP FABRICATION / PREFABRICATION
The purpose of Shop fabrication or prefabrication is to minimise work during
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erection to the extent possible. Piping spool after fabrication shall be stacked
with proper identification marks, so as to facilitate their withdrawal at any
time erection. During the period all flange (gasket contact faces) and threads
shall be adequately fabricated by coating with removable rust preventive. Care
shall also be taken to avoid any physical damage to flange faces and threads.
4.17 ALIGNMENT
The pipes to be jointed by welding shall be aligned correctly with existing
tolerances on diameters, wall thickness and out of roundness and weld gaps.
The same alignment shall be preserved during welding.
4.18 LAYOUT, CUTTING & FITTING UP
)c For laying out headers, tees, laterals and other irregular details, cutting
template shall be used to ensure accurate cutting and proper fit up.
)d All cutting shall follow the outline of the templates.
)e Machine cut bevels to form the welding groove are preferred in carbon
steel pipe. However, smooth, clean, slag free flame cut bevels is
acceptable.
)f Tack welds with full penetration shall be used and shall become the part of
the finished weld and shall be carried out by qualified welders only.
)g Defective welds or tack welds with lack of penetration are not acceptable
and shall be chipped / ground out.
)h No temporary weld attachment shall be with extended clamps / attachment.
4.19 CLEANNING OF PIPING
)a On completion of fabrication, all pipes and fittings shall be cleaned inside
and outside by suitable means (Mechanical, cleaning tool, wire brush, etc.)
before erection to ensure that assembly is free from all loosed foreign
material such as scale, sand, weld, spatter particle, cutting chips etc.
)b All field fabricated piping shall also be cleaned at the competition of the
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fabrication. All burrs, welding circles and weld spatters shall be removed
by any suitable means (Mechanical tools, wire, brush, etc.)
)c Both shop and field fabricated piping shall be blown out with compressed
air at the terminated specification of cleannning and capped.
)d Cleaning requirements for special services, if any, shall be as specified in
the piping material specifications.
)e S.S. jacketed piping requiring picking shall be pickled to remove oxidation
and discolouring due to welding.
5.0 ERECTION
5.1 PIPING ROUTING
Pipe to pipe, pipe to structure / equipments distances / clearance as shown the
drawings shall be strictly followed as these clearance may be required for the
expansion of piping / equipment.
5.2 COLD PULL
Wherever cold pull is specified, maintain the necessary gap, as indicated in
the drawing. Stress reliving shall be performed before removing the gadgets
for old pulling.
5.3 SLOPES
Slopes specified for various lines in the drawings / P&ID shall be maintained
during erection of piping spools.
5.4 EXPANSION JOINTS / BELLOWS
5.4.1 Installation of Expansion joints / Bellows shall be installed in accordance with the
specification and installation drawings.
5.4.2 Each expansion joints / bellows shall be blown free of dust / foreign matter with
compressed air or cleaned with a piece of cloth.
5.4.3 a) For handling and installation of expansion joints, great care shall be taken while
aligning. An expansion joints shall never be slinged from bellows
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corrugations / external shrouds, tie-rods, and angles.
b) An expansion joints / bellows shall preferably be slinged from the end pipes /
flanges or on the middle pipe.
5.4.4 a) All expansion joint shall be procured at “Installation length”, maintained by means
of shipping rods, angles welded to the flanges or weld ends or by wooden or
metallic stops.
b) Expansion joints stop blocks shall be carefully removed after hydrostatic
testing. Angles welded to the flanges or weld ends shall be trimmed by saw as
per manufacture’s instructions and the flanges or weld ends shall be ground
smooth.
5.4.5 a) The pipe end sin which the expansions joints is to be installed shall be perfectly
aligned or shall have specified lateral deflection as noted on the relevant
drawings.
b) The pipes ends / flanges shall be spaced at a distance specified in the
drawings.
5.4.6 The expansion joints shall be placed between the mating pipe ends / flanges and shall
be tack welded / bolted. The mating pipes shall again be checked for correct
alignment.
5.4.7 Butt-welding shall be carried out at each end of the expansion joint. For flanged
expansion joints the mating flanges shall be bolted.
5.4.8 After the expansion joint is installed and shall ensure that the mating pipes and
expansion joints are in correct alignment and that the pipes are well supported
and guided.
5.4.9 The expansion joint shall not have any lateral deflection.
5.4.10 Precautions
1) For carrying out welding, earthing lead shall not be attached with the
expansion joint.
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2) The expansion bellow shall be protected from arc welds spot and
welding spatter.
3) Hydrostatic testing of the system having expansion joints shall be
performed with shipping lugs in position. These lugs shall be removed
after testing and certification is over.
5.5 FLANGE CONNECTIONS
While fitting up mating flanges, care shall be exercised to properly align he
pipes and to check the flanges for trueness, so that faces of the flanges can be
pulled together, without inducing any stresses in the pipes and equipment
nozzles. Extra care shall be taken for flange connections to pumps, turbines,
compressors, cold boxes, air coolers etc. the flange connections to these
equipments shall be checked for misalignment, excessive gap etc. after the
final alignment of the equipment is over. The welding of flange shall be done
only after proper alignment of terminal equipment.
Temporary protective covers shall be retained on all flange connections of
pumps, turbines, compressors and other similar equipments, until the piping is
finally connected, so as to avoid any foreign material from entering these
equipments.
The assembly of a flange joint shall be done in such a way that the gasket
between these flanges is uniformly compressed. To achieve this bolt shall be
tightened in a proper sequence.
5.6 VENTS AND DRAINS
High point vents and low point shall be provided as shown in the drawings.
The details of vents and drains shall be as per piping material specifications /
jobs standards.
5.7 VALVES
Valves shall be installed with spindle / actuator orientation as shown in the
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layout drawings. Care shall be exercised to ensure that globe valves, check
valves, and other unidirectional valves are installed with the Flow direction
arrow on the valve body pointing in the correct direction. If the direction of
the arrow is not marked on such valves this shall be done in presence of
Engineer-In-Charge.
5.8 INSTRUMENTS
Installation of in-line instruments such as restriction orifices, control valves,
safety valves, relief valves, rotameter, orifice flange assembly, venturi meters,
flow meters etc. shall form a part of piping erection work.
Fabrication and erection of piping up to first block valve / nozzle / flange for
installation of offline instruments for measurement of level, pressure,
temperature, flow, etc. shall also form part of piping construction work. The
limits of piping and instrumentation work will be shown in drawing / standard
/ specifications. Orientations / locations of take-offs for temperature, pressure,
flow level connections etc. shown in drawing shall be maintained
Flushing and testing of piping systems which include instruments mentioned
above and the precautions to be taken are covered in flushing, testing, and
inspection of piping (3177-LSS-106). Care shall be exercised and adequate
precautions taken to avoid damage and entry of foreign matter into
instruments during transportation, installation, testing etc.
5.9 LINE MOUNTED EQUIPMENTS / ITEMS
Installation of line mounted items like filters, strainers, steam traps, air traps,
desuperheaters, ejector, sample coolers, mixers, flame arrestors, sight glasses
etc. including their supporting arrangement their supporting arrangements
shall form part of piping erection work.
5.10 BOLTS AND NUTS
M/s L & T shall apply molycoat grease mixed with graphite powder (unless
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otherwise specified in piping classes) all bolts and nuts during storage, after
erection and wherever flange connections are broken and made-up for any
purpose whatsoever. M/s L & T shall supply he grease and graphite powder
without price implication to owner. However wherever bolt tensioning is
called for the lubricants used shall be as per the bolt tensioning specification
duly reviewed by PMC.
5.11 PIPE SUPPORTS
Pipe supports are designed and located to effectively sustain the weight and
thermal effects of he piping system and to prevent its vibrations. Location and
design of pipes supports will be shown in drawings for lines of all sizes. All
supports provided should be as per the location and type considered during the
approval of stress analysis reports. If any change of route is to be done, stress
analysis to be done before carrying out site changes. This is applicable for the
pipelines identified for stress analysis, for rest of the pipelines; supports
should be as per drawing.
No pipe shoe / cradle shall be offset unless specifically shown in the
drawings.
Hanger rods shall be installed inclined in a direction opposite to the direction
in which the pipe moves during expansion.
Preset rods shall be installed inclined in a direction opposite to the direction in
which the pipe moves during expansion.
Preset lock pins of all spring supports shall be removed only after hydrostatic
testing and insulation is over. The following points shall be checked after
installation by designer & consultant with the PMC and necessary
confirmation in writing shall be given certifying that:
All restrains have been installed correctly.
Clearances have been maintained as per support drawings
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Insulation does not restrict thermal expansion
All temporary tack welds provided during have been fully removed.
All welded supports have been fully welded.
Where practicable and except when otherwise shown on the drawings, valve
stems shall be installed in a vertical direction and shall not be installed with
below the horizontal axis.
6.0 PERFORMANCE OF WELDS & HEAT TREATMENT
6.1 PREHEATING
a) No welding shall be performed by without preheating the joint 100C when
the ambient temperature is below 100C.
b) Preheat will be applied with minimum as specified in welding chart.
c) Preheating shall be performed using resistance or induction methods.
Preheating by gas burners, utilising oxy-acetylene or oxy-propane gas
mixture.
d) Preheating shall extend uniformly to at least three times the thickness of the
joint, but not less than 50 mm, on both sides of weld.
e) Preheating temperature shall be maintained over the whole length of joint
during welding.
6.2 POST WELD HEAT TREATMENT
a) Post weld heat treatment, wherever required for joints between pipes, pipes
and fittings, pipe body and supports shall be carried out as per welding
specification chart.
b) Post weld heat treatment shall be done in a furnace or by using electric
resistance or induction heating equipment.
All welding consumable such as electrodes, filler wires, flux and gas shall
be stored, handled and use in accordance with the manufacturers
instructions.
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7.0 WELDING CONSUMBALES
7.1 The welding electrodes and filler wires used shall be as per approved WPS/ welding
specification chart and B.T.C. of electrode / filler wire shall be submitted to
Jacobs for approval.
7.2 All electrodes shall purchased in sealed containers and stored properly to prevent
deterioration. The electrode removed from containers shall be kept in holding
ovens at temperatures recommended by the electrode manufacture. The
electrode shall handled with care to avoid any damage to the flux covering.
7.3 All low hydrogen type of electrodes shall be rebaked at 3500C for 1 hours minimum and
stored in ovens kept at 80-1000C before use.
7.4 The electrodes, filler wires and flux used shall be free from rust oil, grease, earth and
other foreign matter, which affect the quality of welding.
7.5 Tungsten electrodes used shall conform to ASME Sec. II C SFA 5.12 specification.
7.6 Only Owner/ PMC approved brands of electrodes shall be used.
8.0 SHIELDING & PURGING GAS:
8.1 Argon gas with a purity level of 99.995% shall be used for purging.
8.2 The purging shall be maintained during the root pass and for the first filling pass to
minimise oxidation on the inner side of the pipe, unless otherwise specified in
Welding Specification Chart.
8.3 Initial purging shall be maintained for sufficient period of time so that at least 4-5 times
the volume between the dams is displaced in order to completely remove the
entrapped air.
8.4 Dams, used for conserving inert gas during purging, shall be removed after competition
of the welding, and shall be accounted for. Wherever, removal of dams is no
possible after welding, use of water–soluble dams should be made.
9.0 WELDING
a) Qualified welders as per approved WPS, welding specification chart and
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approved drgs, shall carry out all welding.
b) Welding technique / process followed during welding shall be as per
approved WPS.
10.0 VISUAL INSPECTION
Inspection of all welds shall carried out as per ANSI B 31.3 and specification.
Finished welds shall be visually inspected for parallel and axial misalignment
of the work, crack. Inadequate penetration, unrepaired burn-through,
dimensions, and other surface defects, and it shall present a neat workman like
appearance. Under cutting adjacent to the final bead on the outside of the pipe
shall not exceed 0.8 mm in depth of 121/2% of the pipe wall thickness,
whichever us smaller and the cumulative length shall not be more than 50 mm
in any continuous 300 mm length or weld.
11.0 REPAIRS OR REMOVAL OF DEFECT
Defects, which are not within the acceptable limits, shall be removed from the
joint completely by chipping or grinding.
When the whole joint us found unacceptable, the weld and the ends of the
joints shall be restored according to relevant under fabrication.
No repair shall be carried out without prior authorisation of the PMC.
12.0 INSPECTION AND TESTING
12.1.1 All NDT works like as RT, DPT, and MPT, UT etc.shall be
carried out by experienced/qualified personnel as per approved job
procedures.
12.1.2 The application of above NDT for welding shall be as per
inspection class mentioned in NDT specification no. 18-3177-000-l-02-0703-
A4 & approved L&T doc. No.-L&T/MSQ/NDT.SPEC/001
12.1.3 Welding repairs are unavoidable made on PWHT, and then
complete PWHT cycle must be repeated with a second heat chart.
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12.1.4 After PWHT the hardness value on the weld, HAZ and parent
metal shall be measured both using Poldi type or portable hardness instrument
wherever PWHT is applicable and hardness requirement shall be as per
welding specification chart.
12.1.5 The field Hydro-test pressure shall not be less than the greatest
of the following:
11/2 times the maximum sustained operating pressure
11/2 times the maximum pipeline static pressure
Sum of the maximum sustained pressure or the maximum pipeline static
pressure and the maximum calculated surge pressure.
- the field test pressure shall wherever possible be not less than two
thirds of the works test pressure and shall be applied and maintained for at
least four hours.
- Where he field test pressure is less than two-thirds the works test
pressure, the period of test shall be increased to at least 24 hours. The test
pressure shall be gradually raised at the rate of nearly 1.0 kg/cm2/minute.
12.1.6 All above ground pipes shall be tested for leakages to a
minimum hydrostatic test pressure of 10 kg/cm2gauge or as per specification.
12.1.7 The joints of the pipe connecting the testing sections shall be
100% radiographed.
12.1.8 TEST MEDIUM
Construction water shall be generally be used as the testing medium for the
hydrostatic testing of Piping system.
12.1.9 CLEANING / FLUSHING
All system shall be cleaned and flushed free of all dirt, debris or loose foreign
material after testing.
12.1.10 TEMPORARY BLINDS
APPROVED BY L & T REVIEWED / APPROVED BY JACOBS
LARSEN & TOUBRO LIMITEDPAGE NO.- 18 OF 19
DATE:-01.11.2007MSQ (EPCC-1) UPGADATION PROJECT REV.NO.- 0
PROCEDURE FOR AG PIPING FABRICATION & ERECTION
PROCEDURE NO.-LT/MSQ/P/AG/005
Open ends of piping systems such as at pumps or wherever equipment has
been removed or disconnected prior to hydrostatic testing, or at termination
point of piping branch connections shall be blinded off by temporary blind
flange made out of minimum 10 mm hick MS plate.
12.1.11 VENTING
All piping systems and equipments shall be properly vented to remove air
from system during filling or as shown in the drawings.
12.1.12 PRESSURISING
Pressure shall be applied by means of suitable test pump, which shall not be
connected to the system until ready to test. A pressure gauge duly calibrated
shall be provided at the pump discharge for guidance in bringing the system
upto pressure. An authorised operator shall attend the pump constantly during
the test. The pump shall be disconnected after the pressure test is completed.
The test pressure is to be maintained for sufficient time to permit compete
inspection of the system under test but in no case shall the time be less than
ten minutes.
12.1.13 TEST GAUGES
Test gauge shall be installed as close as possible to the lowest point in the
system being tested. Prior to installation, the test gauge shall be checked
against standard gauge or calibrated with the aid of a dead weight tester.
12.1.14 DRAINING
All lines and equipment’s shall be completely drained after the hydrostatic test
of a system has been completed. High point vents shall be open prevent
excessive vacuum and permit complete draining.
13.0 SAFETY
13.1 All safe measures shall be observed in welding and cutting and required PPE shall be
enforced to the job performer.
APPROVED BY L & T REVIEWED / APPROVED BY JACOBS
LARSEN & TOUBRO LIMITEDPAGE NO.- 19 OF 19
DATE:-01.11.2007MSQ (EPCC-1) UPGADATION PROJECT REV.NO.- 0
PROCEDURE FOR AG PIPING FABRICATION & ERECTION
PROCEDURE NO.-LT/MSQ/P/AG/005
13.2 All Safety & regulatory practices during performance of Radiography work shall be
observed particularly personal protection from radiation either by distance, or
time or, shielding, or a suitable combination of all three.
13.3 During Radiography, also Radiation warning signal either visual or sound or both
shall be put to keep the unconnected people away to avoid any exposure.
13.4 During Hydrostatic or Pneumatic testing, people shall be warned by deploying danger
signal and cordoning the area to avoid any accidental injury.
14.0 DOCUMENTATION
All documents shall be prepared and maintained as per approved ITP No. : -
LT/MSQ/ITP/PIPE/AG/002 Rev. 0 and applicable approved formats as per
ITP.
APPROVED BY L & T REVIEWED / APPROVED BY JACOBS
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