METHOD STATEMENT FOR STORAGE TANKS

1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Project

1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant

Method Statement No
CIVIL
ELECTRICAL
MECHANICAL
INSTRUMENTATION

Date
Name
Date
Name

Prepared by

Reviewed by

Safety Release

QA/QC
Approval

Approved by

Section
Engineer

Construction
Manager

Safety
manager

QA / QC
Manager

Project
Manager

Site Manager

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

1. INTRODUCTION
The following is the method statement for the erection of Carbon Steel storage tanks with roof
by Jacking method and covers the following tanks.

a) Fulisilic acid storage Tanks-2nos (234-R-01A/B).
b) Sulphuric acid product storage tanks-3nos.
c) Potable water tank-1nos (245-R-01).
d) Diesel storage tank-1nos (246-R-01).
e) Molten sulphur tank -1nos
. It comes under Sulphuric & Phosphoric acid plant.
2. Function and location, General Description, Scope of Work
a) Function and Location
The function of the storage tank is to store the Concentrated acid / Weak acid / Effluent for
Maturation/Storage purposes, and it was located in phosphoric acid plant area.
b) General Description
a) Fulisilic Acid storage Tank (234-R-01A/B) -2nos. (DIA 12000MM / HEIGHT 18000MM /
NO OF SHELLS 8NOS).
b) Potable water storage tank-1nos (245-R-01). (DIA 4800 / HEIGHT 6050MM / NO OF
SHELLS 3NOS).
c) Diesel Storage Tank- 1nos. (246-R-01) (DIA 11000MM / HEIGHT 8675MM / NO OF
SHELLS 4NOS).
d) Sulphuric Acid storage tank- 3nos. (DIA 28500MM / HEIGHT 10000MM / NO OF SHELLS
5NOS).
e) Molten sulphur Storage tank– 1nos. (DIA22000MM / HEIGHT7840MM / NO OF SHELLS
4NOS).
I-BEAMS of IPE-270
Ladders, Walk ways Flat forms and handrails etc
Baffle plates
Tank roof
c) Scope of work
Erection of I-Beams on the civil foundation and leveling.
Erection, Alignment, Fit up and welding of bottom base plate.
Inspecting welding with required NDT procedures like DP Test, Radiography, and Vacuum
box UT etc (refer-ITP).

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Erection, Alignment of Tank course shells by jockeying method.
Erection of roof.
Erection of Internal Baffle plates, Dip tube etc.
Erection of Walk ways, staircase, Agitator support, Hand railing.
Erection of Ladders, Flat forms and Hand rails.
3. Related Documents
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Technical specifications.
Approved construction drawings.
Weld map.
Release of material for construction form SNC Lavalin.
Release certificate starting of erection over civil foundation from MID.

Vendor’s instruction/manual required.
I.T.P (Inspection Test Plan)
All last revisions of Drawings, WPS, PQR, Welder certificated, etc

4. Required Material Testing, during and before work
Material grade to be confirmed for WPS/PQR/WELD Qualification.
Batch number, Heat number punched on the plate to be compared with Mill certificate.
5. Environmental and Safety
All the lifting tools gear like slings, belts, D-Shackles etc are of Tested & Certified by the TPI.
Cranes involved in Erection are certified by TPI.
All the PPE used for the work is of approved quality.
All the Workers, Staff, Engineers involved in work are geared with full basic PERSONAL
PROTECTION EQUIPMENT.
TOOL BOX TALK will be conducted on daily basis at the starting of the job.
When working at height above 1.5mts from the ground every person to be wearing a safety belt.
When working at height proper scaffolding will be provided for accessing, testing, inspection for
the client.
Scaffolding work will be done by properly trained and certified workers only under the
supervision of Engineer.
Entry Permit system for usage of scaffolding will be practiced.

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

While starting of welding, gas cutting, grinding, gouging operations HOT WORK permit system
will be practiced.
All the gas cutting torches are installed with approved Flash back arrestors.
All the welders are with proper hand gloves, Apron, Face shield and other additional required
safety gears.
While working in confined space CONFINED SAPCE ENTRY PERMIT system will be practiced.
All the power tools are of certified and tagged properly.
All the power, welding cables are of certified and tagged properly.
For handling Plates special lifting tools like horizontal and vertical plate lifting tools are used.
Good housekeeping will be practices at all the time.
Fire extinguishers are kept near the work for any fire incidents.
Gas cylinders are stationed during work so that they maintain required distance from the heat
source.
Best engineering will be practiced to avoid accidents.

6. Detail of work supported with sketches and with special highlight for details
• Extension of I Beams to the required length. (Refer to QI(QUALITY INTERNATIONAL)
procedures).
• Inspection of welding.
• Erection of I-Beams on slab.
• Aligning & Leveling of I-Beams.
• Anchoring of I-Beams of to the concrete foundation.(Hold)
• Erection of Bottom base Plate on the I-Beams.
• Fit-up and Welding of Bottom base plate.
• Inspection of welding By Penetration, RT, and Vacuum test.
• Erection of Shell-5 plate on the bottom base plate and alignment with fit up
• Vertical welding of shell-5.
• Inspection of vertical & Horizontal by RT through 10% of the total length of the welding.
• Erection of shell-6 on the top of shell-5 and followed by alignment, fit up and welding of vertical

& horizontal welding.
• Inspection of vertical & Horizontal by RT through 10% of the total length of the welding and
100% RT of the T-Joints.
• Erection and fabrication of Roof.
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

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Installation and fabrication of available Baffle plates.
Erection of Hydraulic jacks inside the tank and distribute symmetrically such that every jack per
3 meter of the circumference.
Installation, erection of walk ways and hand railings if advised.
Lifting of the shell-5 by 2450mm height by hydraulic jacks.
Erection, alignment and fit up of shell-4.
Welding of horizontal and vertical welds.
Inspection of vertical & Horizontal by RT through 10% of the total length of the welding and
100% RT of the T-Joints.
Lifting of the shell-4 by 2450mm height by hydraulic jacks.
Erection, alignment and fit up of shell-4.
Welding of horizontal and vertical welds.
Installation and fabrication of available Baffle plates.
Inspection of vertical & Horizontal by RT through 10% of the total length of the welding and
100% RT of the T-Joints.
Lifting of the shell-4 by 2450mm height by hydraulic jacks.
Erection, alignment and fit up of shell-3.

Welding of horizontal and vertical welds.
Installation and fabrication of available Baffle plates.
Inspection of vertical & Horizontal by RT through 10% of the total length of the welding and
100% RT of the T-Joints.
Lifting of the shell-3 by 2450mm height by hydraulic jacks.
Erection, alignment and fit up of shell-2.
Welding of horizontal and vertical welds.
Installation and fabrication of available Baffle plates.
Inspection of vertical & Horizontal by RT through 10% of the total length of the welding and
100% RT of the T-Joints.
Lifting of the shell-2 by 2450mm height by hydraulic jacks
Erection, alignment and fit up of shell-1.
Welding of horizontal and vertical welds.
Installation and fabrication of available Baffle plates.
Inspection of vertical & Horizontal by RT through 10% of the total length of the welding and
100% RT of the T-Joints.
Welding of Bottom shell -1to the Bottom base plate.

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

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Installation of Nozzle, pipe supports, flat forms, ladders, agitator supports and handrails.

7. Curing and Weather Protection
All the plate will be supplied with sand blasted and primer coated by QI.
All the welding edges will be protected by tape while painting.
Any additional welding made on painted are will be power brushed and coated again.
For locations with scratches, burns on painting etc during erection will be painted again.(rev-1)
8. Show hold points for internal and external required inspection including specified tests on
products.
Fit up inspection for levels, weld gaps, etc.
Vacuum test of welding of the bottom base plate.
While welding Test of root pass with penetration test.
Horizontal and vertical welds 10 % of the total length by RT.
RT test for the T-Joints by 100%.
9. Construction Equipment to be used , including standby Arrangement for breakage
While the shells are erected by Jacking of the top shells with Hydraulic Lifting Jacks which are
activated by a power pack. A standby power pack is available for breakage. And numbers of
spare hydraulic hoses are available for breakage.
10. Lifting equipment, involved (where applicable, crash, tower crane…test and location).
For handling of plates cranes will be used for shifting, lifting, erection and purposes.
11. Tools and associated other contractors Apparatus involved in this
The following tools are involved in work
• Welding Rectifiers machine.
• Gas cutting torch.
• Grinding machines of different sizes (100mm, 125mm and 150mm).
• Owen for baking of electrodes.
12. Manpower involved and Trades, who does what and when.
Supervisor for Tanks: - He takes care of all the activities associated in erection and fabrication of
tanks and he involved in all the activities from staring to the finishing.
Riggers: - These will involve in handling the plates for erection, alignment etc.

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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Fabricator/ Fitter: - He is responsible for fit ups, alignments, verticality and tolerances of the
total tank.
Lifting Forman/ Jacking Specialist: - He takes the takes the lead role in alignment and
positioning of Hydraulic lifting Jacks, He takes the leading role in lifting of the tank shells at every
step.
Pipe Fitter: - He takes the fit up of nozzles and other pipe supports and structural items.
Welders: - These will do all the welding operations.
Grinders: - These will do grinding operation for the tank.
Helpers: - These are the general helpers to skilled workers involving in job.
Crane operator: - These will operate the crane.
QA/QC Team: - These will guide the job for required QA/QC levels.
13. Work Schedule Requirements’ and Timing for This work.
For this job the daily regular work hours will be 10 hrs excluding lunch time.
From 7-00Am to 6-00PM.
On weekly half’s required core skilled workers like welders will be engaged if necessary.
14. Training and Orientation for the Team
For all the team members TOOL BOX TALK will be conducted at the beginning of activity on daily
basis.
The scaffolding team will be of trained and certified.
The crane operator will be of trained and certified.

The riggers involved will be of trained and certified.
Regular monitor of welders and if necessary training will be given regularly.
15. Tests on Systems (QA /QC )
Radiographic Test of all T-Joints by 100%.
Vertical & Horizontal welding RT by 10 % of the total length of the welding.
Vacuum test for the Base plate.
Dye Penetrate Test for all Root pass and Final.
In case Repair is needed, extension shots (penalty) to be match with API650
To be advised for any other test is needed.
16. Logistics involved if work is expected to extend beyond normal working hours.
Lighting while working at night.
Shade protection while the wind velocity is very high.
METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

17.

Annexes and sketches lists.

WEIGHTS OF THE INDIVIDUAL MATERIALS for crane, lifting gear selection purpose.

1. IPE 270 TANK BOTTOM BEAMS

2. CS Plate of 2400mm Width X 12000mm Length mm X 16mm Thick = 3.617 Tones.
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Isometric view of foundation after erection of I beams.

Close up view of foundation, I Beams and bottom plate.

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Erection, fit up and welding of bottom plate segments.

Erection of 1st shell plate on bottom plate.

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0

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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Complete erection, fit up & vertical welding of 5th shell.

Erection of 6th shell plate on 5th shell by conventional method.

Keeping vertical joints plates adjoining courses a minimum of 600mm apart.
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Complete erection, fit up, vertical & horizontal welds of 6th shell.
Erection, fit up, welding of spiral stair case for the shells completed.
Erection, fit up, welding of Baffles and stair case subjected to availability of material for 5th & 6th
shells.

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Erection fabrication of Tank Roof before jacking

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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Lifting of 5th & 6th shells by hydraulic jacks.

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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

4th shell 1st plate erection, alignment on bottom plate.

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

4th shell 2nd plate fit up.

Complete erection, fit up and vertical welding of 4th shell

Jockeying down the 5th shell to align with the 4th shell, fit up and completion of horizontal welding.

Erection, fit up, welding of Baffles plates, staircase etc subjected to availability of material and
approval for 4th shell.
METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Lifting of 4thshell for 3rd shell erection.

Erection of 3rd shell first plate.
METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Erection fit up of 3rd shell 2nd plate

Complete erection, fit up and vertical welding of 3rd shell plates.
METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Jockeying down to align top shells with 3rd shell, horizontal welding of 4th & 3rd shells.
Erection, fit up, welding of Baffles plates, staircase etc subjected to availability of material and
approval for 3rd shell.

Lifting the 3rd shell for 2nd shell erection

METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Erection of 2nd shell first plate.

Complete erection, fit up and vertical welding of 2nd shell.
METHOD STATEMENT FOR STORAGE TANKS WITH ROOF Rev-0
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1500 MTPD Phosphoric Acid plant
4500 MTPD Sulphuric Acid plant
METHOD STATEMENT

Jockeying down for alignment, fit up & horizontal welding between 2nd shell & 3rd shell.
Erection, fit up, welding of Baffles plates, staircase etc subjected to availability of material and
approval for 2nd shell.

Lifting 2nd shell for 1shell erection and fit up.
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