ERECTION STEEL STRUCTURE PROCEDURE | METHOD STATEMENT

1.0 PURPOSE
2.0 SCOPE
3.0 APPLICABLE DOCUMENTS
4.0 RESPONSIBILITY
5.0 SAFETY PRECAUTION
6.0 MANPOWER
7.0 TOOLS & EQUIPMENT
8.0 METHODS! PROCEDURES
9.0 QUALITY CONTROL
10.0 ATTACHMENTS

ERECTION STEEL STRUCTURE PROCEDURE | METHOD STATEMENT

1.0 PURPOSE

1. This method statement will serve as a minimum guideline in the erection of pipe racks for in plants and refineries.

2.0 SCOPE

2.1 This method statement will cover the erection of all pipe racks of in plants and refineries.

3.0 APPLICABLE DOCUMENTS

3.1 Specification and Standards

3.1.1 Construction Scope of Work.
3.1.2 Construction Specification for Steel Structures Shop Fabrication.
3.1.3 Construction Specification for Steel Structures Site Erection.
3.1.4 Construction Specification for High Tension Bolt Tightening.
3.1.5 Supplementary Specification for External Coating.

3.2 ARAMCO Specification and Standards

3.2.1 SAEP-302 Instruction for Obtaining a Waiver of a Mandatory Saudi ARAMCO Engineering Requirement
3.2.2 SAES-B-OI4 Safety Requirement for Plant and Operations Support Buildings
3.2.3 SAES-M-OO I Structural Design for Non-Building Structure
3.2.4 SAES-Q-IO Cement Based, Non-Shrink Grout for Structural & Equipment Grouting
3.2.5 12-SAMSS-007 Fabrication of Structural and Miscellaneous Steel
3.2.6 12-SAMSS-008 Erection of Structural and Miscellaneous Steel
3.2.7 SCHEDULE Q Saudi ARAMCO Project Quality Requirements
3.2.8 Saudi ARAMCO Safety Requirements for Scaffolds
3.2.9 Saudi ARAMCO Construction Safety Manual

3.3 Industry Codes and Standards

3.3.1 AISC Code of Standard Practice, Specification for Structural Joints UsingASTMA325 orA490 Bolts.
3.3.2 AWS 01.1 Structural Welding Code
3.3.3 PIP STS05130 Erection of Structural and Miscellaneous Steel Specification
3.4 Inspection and Test Plan / Method Statement
3.4.1 SATlP-M-OOI-OI Structural Steel- Piperack, Steel Supports & Miscellaneous Steel Structures
3.4.2 SATIP-Q-OIO-OI Cement Based Non-Shrink Grouting
3.4.3 SATR-M-2002 Pre-Installation Procedure Verification testing Using the Turn-of-Nut Method (ASTM A325 or ASTM A490 Bolts)
3.4.4 SAIC-M-2009 High Strength Bolts Tightening Inspection and Testing (ASTM AI325 or A490 Bolts)

3.4.5 SAIC-M-2006 Inspection of Support Foundation Prior to Structural or Equipment Installation.
3.4.6 SAIC-M-2007 Inspection of Structural Alignment During Erection.

4.0 RESPONSIBILITY

4.1 Construction Manager is responsible for overall implementation of HSE, and shall study, analyze and schedule all construction activities with his department to include manpower and equipment line up as well as other possible resources required for the successful implementation of the construction work activities. Study all aspects of work procedure as per Technical Scope of Work.
4.2 Structural Supervisor is responsible for all HSE matters of the works and shall, study and review all necessary documents for the erection works in his area to include, technical scope of work, specification, bill of quantities, planned milestone dates and construction procedure in support to his Structural Foreman. He shall monitor the availability reporting to the Construction Manager. He shall coordinate with other discipline to visualize possible conflicts in the drawings as well as in the schedules to provide other options in preventing unnecessary delays obstructions.
4.3 Structural Foreman shall be responsible for all HSE matters and for the direct work supervision at site and ensure that the work is performed in accordance with Technical Scope of Work and latest approved for construction drawings. He shall monitor the availability of materials in line with his required schedule.

4.4 Surveyor shall study and analyze if the location where the structure should be installed satisfies the condition 01′ restriction of erection works on site. He shall coordinate with other discipline to visualize possible conflicts in the drawings as well as in the schedules to provide other options in preventing unnecessary delays obstructions.

4.5 QC Inspector shall be responsible in monitoring and inspection of the work and ensure that the work is performed in accordance with Technical Scope of Work and Standards.
4.6 Safety Engineer/Supervisor shall be responsible in monitoring safety aspects and ensuring that the work is done in accordance with Safety Standard Procedure. He shall discuss to the workers of the characteristics of related materials and status of work area giving reminders as an additional point to work safely.

5.0 SAFETY PRECAUTION

5.1 Approved work permit should be obtained prior to the start any structural works.
5.2 Work execution shall be carried out in accordance with this method of statement.
5.3 Erection crew must carry out a safety risk assessment prior to the start of any new activities.
5.4 During any lifting works, signalman must be assigned full-time.
5.5 The necessary manpower inclusive of supervisory staff, tools, equipment, materials, and other resources required must be made available and ready to use.
5.6 Workers should be provided with and wear their PPE’s needed for work.
5.7 A Fire Watcher with fire Extinguisher shall assign for any hot work activity.
5.8 Certified permit receiver, fire watcher, traffic flag man and work-in-charge should be at work site during the execution of the work.

5.9 Use of special Man basket (engineered lifts) is subjected for inspection prior to be utilized on steel erection works.(Rigger I required to sign man-basket permit.)
5.10 Personnel who will be working from a suspended workbasket should secure Suspended Personnel Work Basket Authorization 1 Permit prior to start work. And have dedicated lifting gear.
5.11 Man basket shall be inspected and be tagged with Saudi ARAMCO Certification.
5.12 Man lift equipment shall be tested and certified by the Saudi ARAMCO Equipment Inspection Division.
5.13 Only certified man lift operator(s) shall be allowed to operate the man lift equipment.
5.14 Sufficient lighting shall be provided if work is done at night time. Work at night shall be approved by client.

6.0 MANPOWER

6.1 Manpower will consist of the following, but not limited to as listed below:

  • Supervisor
  • Foreman
  • Crane Operators
  • Surveyor
  • Man lift Operator
  • Truck Drivers
  • Structural fitters
  • Riggers
  • Plate welders
  • Scaffolders
  • Semi-skilled workers
  • Safety

7.0 TOOLS AND EQUIPMENT

7.1 Tools and equipment will consist but not limited as below:

  • Hydro Crane 150/70/60 tons
  • Crawler Crane 180 tons
  • Man lift
  • Trailer
  • Boom truck
  • Welding machine
  • Air compressor
  • Towel’ lights
  • Man-basket
  • Impact tools

8.0 METHODS / PROCEDURES

8.1 General Preparatory Work

8.1.1 Confirm the turnover of civil works foundation/pedestals form civil for the installation of pipe racks.
8.1.2 Secure necessary work permit Representative prior to start of work/activity.
8.1.3 Check foundations and other connection points to confirm locations, orientation levation and condition.
8.1.4 Identify the structure members for leave-out (if any) due to installation of equipment and other prerequisite.
8.1.5 Mobilize all manpower, tools and equipment needed for the job.
8.1.6 Prior to turnover, ensure that the completed foundation with anchor bolts was already checked and its dimensions, levelness, alignment, top ofconcrete elevation,surface finish, and others are as per the latest
revision of drawings and within acceptable tolerances. Conduct inspection using SAIC-M-2006.

8.2 Anchor Bolt Setting

8.2.1 Anchor bolts shall be installed as shown on the design drawings.
8.2.2 Contractor to coordinate with other trades when inserts placed by others are required.
8.2.3 Contractor to fill voids in sleeves with readily removable material to prevent the entry of concrete, dirt, etc.
8.2.4 Anchor bolts shall be positioned and secured within the tolerances as per design drawings.
8.2.5 Wooden templates shall be used to securely position all column anchor bolts.Templates shall be supported independent from the reinforcing steel.

8.2.6 Unless shown otherwise, anchor bolts shall be set perpendicular to the theoretical bearing surface.
8.2.7 Anchor bolts shall be securely held in position and shall be checked by Contractor immediately after the concrete is placed.
8.2.8 After the concrete has hardened sufficiently, the exposed portion of anchor bolts shall be cleaned of all concrete and the thread chased. Threads shall be carefully coated with grease and the washers and nuts installed.

8.2.9 Anchor bolts shall be protected with plastic wrap on its thread before pouring.

8.3 Installation and Grouting of Packer Plates

8.3.1 Clean the top ofbearing surfaces and bottom of base plates. Set and shim column base plates to correct positions, elevations, and locations as shown on the latest approved erection drawings. Shims and wedges to be used shall be provided by Contractor, setting nuts shall be loosened before grouting as per PIP STS05 1306.4.I.
8.3.2 Ensure that the top of foundations have been properly roughened for bondingLaitance, oil, grease, dust, sand and other foreign matter shall be removed if any.

8.3.3 Dry Pack Grouting

8.3.3.1 Contractor shall conduct one (1) time sampling/testing for dry pack grouting during setting of packer plates to ensure compressive strength of grout materials conforms to requirements.

8.3.3.2 Mixture of grout to be used for installation of packer plates shall be dry pack “non-shrink packer plates shall be dry pack “non-shrink cementitious grout” in accordance with manufacturer’s recommendations.

8.3.3.3 Sampling, curing and testing grout specimen shall follow procedure as specified in Method Statement for Non-shrink Grout Installation.
8.3.4 Setting of packer plates or other adjusting devices shall be in a manner that will ensure structural members are located in correct positions and elevations.
8.3.5 Install packer plates in location(s) as applicable in-between anchor bolts of concrete pedestal. Packer plates will be coated as pet applicable coating system schedule. Grade ofpacker plate shall be ASTM A36/ASTM A36M as per 12-SAMSS-007 sec. 4.2.

8.3.6 Conduct inspection for elevation and location of installed packer plates.
8.3.7 Upon acceptance and curing of dry pack grout installation and packer plates setting, erection of pipe rack shall commence.

8.4 Preassembly and Erection

8.4.1 All materials shall be place on designated area near the location for assembly anderection.
8.4.2 Surface ofsteel structural member shall be clean by air blowing on ground prior Forlifting work.
8.4.3 Provide dunnage underneath to avoid materials on direct contact with soil andprotect from dirt.
8.4.4 After pre-assembly check ifthe bolt for Main Frame is already at Fully tight condition by using Calibrated Torque Wrench. Tightening for loose material after installation may use Electric Impact Wrench. Marked the bolt as applicable.
8.4.5 Lifting of painted structural shall be done with non-abrasive choker.

8.4.6 The crane responsible for loading or unloading structural members shall beassigned separately prior for erection works.
8.4.7 Position the cranes(s) on designated area. Crane #1 (I SOT minimum) shall be responsible for the pre­ assembly of column and girders in ground level and assisting crane #2 for erecting frame assembly. Crane #2 (70T minimum) shall be responsible for the erection of frame assembly from ground level to its designated location and assisting erection ofgirders connecting frames. Crane #3 (60T minimum) shall be responsible for the erection of girders connection to erected frames, tie beams and bracings. The ground where the crane(s) will be position shall be stabilized. Clearance for the crane access way shall establish and maintained in the duration of works.

8.5 Pre-alignment of structure

8.5.1 After completion ofsteel erection, plumbness checking and alignment of erected structure shall commence form Grid lines until the alignment and plumbness ofall columns have been checked and corrected. QC inspection shall follow to verify alignment and plumbness records as per SATlP-M-OOI-OI. Plumbness/alignment checking and correction works shall progress continuously after erection ofstructure until it reaches.
8.5.2 Alignment inspection for completed steel structure shall be done prior to welding and final bolting  tightening; steel structure shall be totally inspected for accuracy ofconstruction and to ensure that all
dimensions are as specified.

8.5.3 Inspection records shall be prepared by Contractor and shall be submitted toARAMCO for approval.

8.6 Bolt Tightening

8.6.1 After QC inspection and acceptance of pre-alignment records, bolt tightening shall be done at all Grid lines of Pipe rack.

8.7 Platforms and Access-ways assembly and installations

8.7.1 Platforms and access-ways on pipe rack shall be installed after the structure is fully erected. Refer to “Erection of Platform and Access-Way” for detailed procedure.

8.8 Detailed Procedure on Bolt Tightening

8.8.1 Bolts Connections / General Requirements

8.8.1.1 ASTM A325M bolts shall not be reused.

8.8.1.2 Where ASTM A307 bolt assemblies are used for connecting miscellaneous items (i.e., handrail assemblies, pipe supports, gates, etc.) to structural members, the bolts shall be tightened to snug tight condition.
8.8.1.3 Workers shall color code the ends ofthe tightened bolts by placing a yellow paint mark indicating that the bolts have been properly tensioned and are ready for inspection.
8.8.14 Workers shall initiate form SAIC-M-2009 to ARAMCO PID for Bolt Tightening Inspection and Testing.
8.8.1.5 Enlargement ofbolt holes for the correction ofmisalignment shall be byreaming or drilling only. Flame cutting, burning shall subject to ARAMCO approval.

8.8.1.6 The mill certificates for the faster materials shall meet ASTM specification.
8.8.1.7 Prior to commence work, impact wrench shall be properly calibrated to desiredtension using bolt tension calibrator. Calibration ofbolt tension calibrator shall be in every six (6) months or stringent requirements of schedule Q-IV-4, Sec. 6.1 shall apply.

8.8.2 Bolt Tightening Condition

Tightening condition shall be in accordance with sec. 4.4 and 4.5 as noted in the standard drawings. Bolt applicable for the bolt tightening procedure shall be ASTM A325M for M20, M24 and M30.

8.8.2.1 This tightening method should be applicable for the various types ofstructures connection details as specified in the drawings, and various structure IFC drawings and various structure IFC drawings as indicated as the following abbreviation.

8.8.2.2 Type of connection for Snug Tight condition

– S*(** such as L, S, R, RL), CS, CSF, LT, HY, LTE, HYE, HYI, H, K, V, El, IJ; Structuremember (e.g. UB254831-SL).
o -No additional or excess tightening force shall be applied to the bolts where snug tight condition has been confirmed.

8.8.2.3 Type ofconnection for Fully Tightening Condition

– This tightening method should be applicable for the various types ofstructure connection details as specified in the drawings and various structure IFC drawings as indicated as following abbreviations.
-EM ( such as EMTB, EMBH); Structure member (e.g. UB610x140-EMB)

8.8.3 Snug Tight Procedure

8.8.3.1 Check the fastener assemblies (bolt, washer and nut) combination, diameter, length and grade to be used in the connection of joints.

8.8.3.2 Aligned all bolt holes for the insertion of bolts to avoid damage on the threads.

8.8.3.3 Placed bolts in all holes with washers positioned and nuts threaded to complete assembly by finger tight.

8.8.3.4 By using ordinary spud or manual wrench, the iron worker shall equally tighten the bolts and nuts until the connected piles are in firm contact, but not necessarily continuous contact.
8.8.3.5 There must be no gaps between the layers of steel where bolt penetrate the steel, these gaps must be away from the bolt holes, 25 mm minimum contact around hole, but not less than the bolt diameter.

8.8.3.6 Tightening shall be progress systematically from the rigid part of joint to its free edges. Secure loosen bolt among bolt assembly.
8.8.3.7 Re-tightening of bolts as per above procedures shall not be considered as a reuse.
8.8.3.8 To confirm whether the bolt connection is in snug tight condition, the protruding end of the bolt and nut shall be marked by yellow paint as shown in Fig. IA and Fig. 1B to indicate that the bolts have been properly tightened after inspection by test hammer.
– For S’ (‘” such as L, S, R, RL), CS, CSF, LT, HY, LTE, HYE, HYI, H, K, Y, EJ, IJ; Structure member (e.g. UB254 x31-SL).

Figure 1. Marking of Snug Tight Connection Only

Marking of Snug Tight Connection Only
Marking of Snug Tight Connection Only

8.8.3.9 In case snug tightening shall be done using impact wrench, the following procedure specified in SATR-M-2002 shall be done prior for commencement ofthe work.
8.8.3.10 Tighten the nut to the value pre-set to impact wrench.
8.8.3.11 Confirm match-matched connection following procedure in Fig. lB.

8.8.4 Fully Tightening by “Turn of Nut” Method

8.8.4.1 Prior to the application of Turn of Nut pre-tensioning, the bolted joint assembly shall be in snug tight condition.

8.8.4.2 After all bolts are in snug tight condition and match-marked, the nut or bolt head is rotated to the amounts of turn specified in Table A (refer to attachment B).
8.8.4.3 Rotation ofthe nut or head is applied to all fastener assemblies in the joint, progressing systematically  from the most rigid part of the joint in a manner that will minimize relaxation of previously pre-tensioned bolts.
8.8.4.4 To confirm if the bolt is in Turn-of-Nut condition and properly tensioned, see Fig. 2 as illustrated

Fig. 2. Match marking of Turn-of-Nut Method

Match marking of Turn-of-Nut Method
Match marking of Turn-of-Nut Method

8,8.5 Pretensionning Procedure Verification Testing

8,8,5,1 Prior to installation of fastener assembly, confirm ifthe tension calibrator is properly calibrated, pre tensionning demonstration shall be conducted to confirm the sequence of work,

8,8,5.2 Take three (3) representative samples ofcomplete fastener assemblies (bolt, nut and washer) of each combination of diameter, length, and grade and lot to be used in testing activity,

8,8,5.3 Assemble the first set ofbolt, washer and nut combination into a tension calibrator, and then tighten the bolt on snug tight condition, Match mark the bolts and nuts as shown in Fig. 1B.

8,8,5.4 Snug tight is defined as the tightness that exists when the plies ofthe joint are in firm contact. This may be attained by a few impacts of an impact wrench or the full effort ofa man using as ordinary spud wrench,

8,8,5,5 Following this initial operation, bolts in the connection shall be tightened further by the applicable amount ofrotation specified in Table A (refer to attachment B),

8.8,5,6 The test shall be verified that the pretensionning method develop a pretension that is equal to or greater than 1.05 times the tension required by Table B (refer to attachment B).

8.8.5,7 Remove the assembly and repeat the procedure until all three (3) samples have been tested.
8.8.5.8 Verification and inspection shall be conducted in accordance with SATR-M-2002 to M20, M24 and M30 bolts,
8.8.5,9 Visual inspection after pretensionning is required to ensure that fastener assemblies are matched-mark as illustrated to Fig, 2.

8.8.5.10 A calibrated tension calibrator shall be onsite when tightening is to be performed on pre-tensioned joints.
8.8.5.11 Test report shall be prepared in accordance with SATR-M-2002.

8.9 Final Alignment

8.9.1 Prior for final grouting, final alignment inspection shall commence to ensure structure plumbness following the tolerances specified in Appendix I “Erection Tolerances” on Specs, unless
otherwise specified on design drawings and/or erection plans.
8.9.2 Conduct final alignment inspection using SAIC-M-2007.

8.10 Final Grouting

8.10.1 Subsequently the erection and final alignment of structures is done, final grouting of packer plates shall commence to complete the erection works. Installation, curing, and inspection as specified in para. 6.1.5.2.

8.11 Welding works

8.11.1 Whenever that field welding is required, the welding for main steel members and important joints of steel structures shall be performed in accordance with AWS D 1.1.
8.11.2 Welders shall have valid qualifications which have been certified by means of Job Clearance Card as per SAEP-323 & SAEP-324.
8.11.3 Welding equipment to be used shall be properly calibrated prior to use at site.
8.11.4 Welding equipment shall always be electrically grounded when in use.

8.12 Touch-up Application

8.12.1 As mentioned in Specs., when damaged painting or galvanized surface on surface on steel structure is observed, and the unpainted area by masking at connection is exposed, surface shall be touch-up.

8.12.1.1 All repaired, reworked, damage galvanized steel supports and gratings will be coated as per applicable coating system schedule.

9.0 QUALITY CONTROL

9.1 QC Inspector will be assigned to attend to the quality control and assurance of this work.
9.2 QC Inspector shall be responsible to conduct all required inspection to ensure that all applicable requirements, codes and standards are complied with.
9.3 QC Inspector will produce all the documents attesting to the acceptability of the works and submits to ARAMCO.
9.4 QC Inspector has to utilize the applicable SATIP’s & SAIC’s for every activity.

Job Safety Analysis

Bolt Tightening Table

Bolt Tightening Table

Bolt Tightening Table

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