Bolt Tightening Manual

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ISO 9000

BOLT TIGHTENING MANUAL

FOR

THAI OIL PUBLIC COMPANY LIMITED

AU UDOM, SRIRACHA, CHOLBURI

THAILAND

THIS DOCUMENT IS ISSUED UNDER THE AUTHORITY OF

...

(SURACHAI SAENGSAMRAN)

ENGINEERING TECHNICAL SERVICES MANAGER

Code No.

ENTS-QQM-06

Issue Date

13

th

_{August 2010}

Issue No.

03 Page No.

1 of 15

Manual Copy No.

Original

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ISO 9000

บันทึกประวัติการแกไข (Amendment Records)

Title:

BOLT TIGHTENING MANUAL

Issue No./

Revision No.

Date

Corrected Part

Reasons for Correction

01/00 04/06/04 Whole Document First Issue 02/00 15/02/05 Whole Document Because of

- Change company name from

“THAI OIL COMPANY LIMITED” to “THAI OIL PUBLIC COMPANY LIMITED”

- Thai Oil has registered its company as “THAI OIL PUBLIC COMPANY LIMITED” as of 09/08/04

- Change the document format - Revised MQOC-QPR-01 - Change document code from QPR-08 to

ENTS-QQM-06

- Add Item 7 Attachment

03/00 13/08/10 ทั้งฉบับ เนื่องจาก - เปลี่ยนผูอนุมัติเอกสารจาก “RICHARD RAVESTEIN”

เปน “SURACHAI SAENGSAMRAN”

- ปรับองคกรเมื่อวันที่ 01/10/09

- เพื่อใหสอดคลองกับการปฏิบัติงานในปจจุบัน - แกไข หนา 3 ขอ 1. Definitions เพิ่ม “Manual Tightening,

Standard Flange และ Hot service ”

- แกไข หนา 4 ขอ 2. Objective แกไขรายละเอียด - แกไข หนา 5 ขอ 3. Scope แกไขรายละเอียด

- แกไข หนา 6 ขอ 4. Work Flow Diagram แกไขรายละเอียด - แกไข หนา 7 ถึง 14 เพิ่มขอ 5 ถึงขอ 12 ทําใหลําดับขอ เปลี่ยนไปตามลําดับ - แกไข หนา 15 ขอ 14. Reference Document แกไข รายละเอียด -- 13/08/10 - แกไข Attachment A, B และ C แกไขและเพิ่มเติม รายละเอียด

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ISO 9000

PROCEDURE NAME

:

BOLT TIGHTENING MANUAL

1. DEFINITIONS

Manual Tightening : Tightening of a stud bolt using manual spanner.

Torque Tightening : Tightening of a stud bolt using hand or hydraulic tools in a turning motion of

the nut against the flange to a predetermined torque setting.

Bolt Tensioning : Is the method of stretching a stud bolt axially to a pre-determined load using

high pressure hydraulics. Tensioning tools can be used in combinations to allow simultaneous tensioning of a number of stud bolts for even loading of a flange. This leaves the stud bolts in a set and even tension.

Standard Flange : Flanges which are compliance with ASME B16.5 or ASME B16.47 (series B).

Hot service : Service with temperature >300 C

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ISO 9000

2. OBJECTIVE

Joint leakage due to improper installation and lack of preventive maintenance can greatly impact plant productivity and cause safety risks and environmental hazards. The installation process is as critical as the design and quality of the gasket itself. In fact, a study by the Application Engineering Department at Garlock Sealing Technologies (Palmyra, NY) found that 82 percent of gaskets returned for analysis (after the joint leaked) showed signs of problems with compression. Normally sufficient torque must be applied to create the compressive load that causes the gasket to consolidate and flow into and fill any irregularities in the sealed mating surfaces. Of the 100 failed gaskets in the study, 68 of the failures were attributed to under-compression (insufficient torque) and 14 to over-compression (excessive torque).

Figure 2 Chart indicates the failure mode of flange joint damage

For a given nominal torque value, the deviation in the final tightening load of the bolt can vary between +/-20% in good conditions, and +/-60% in bad conditions. This wide range is due to the combination of the following 2 factors;

- The tolerance in the applied torque and bolt stress, which can vary from +/-5% to +/-50% depending on the method

- Geometric defects and surface roughness (degree of lubrication) on the threads and the bearing surfaces of the fastened components

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ISO 9000

The target of this procedure is to ensure “zero flange leakage on start-up”. This is being considered to be an achievable target and one which is cost-effective compared to the consequence of leaks both in terms of HSE impact and financial loss. The purposes of this document are;

2.1 To provide guideline for bolt tightening methodology selection based on service application and flange/bolt size. Also provide torque value which sufficient for minimum seating stress required and within bolt stress limit.

2.2 To control the geometric defects i.e. the flange assembly work steps included equipment basic inspection for quality assurance.

3. SCOPE

This manual covers stud bolt joints applied to both standard and non-standard flange included pipe-to-pipe joint, pipe-to-pipe-to-equipment joint, and all pressure container flange e.g. manhole, channel box cover, shell cover, etc. with all gasket type. The operating temperature is needed to be below 450 deg C (80% stress relaxation for B7 and B16). For higher service temperatures, more stringent controls e.g. hot bolting may need to be applied.

Stud bolts which are able to applied bolt torque mentioned in this manual included A193 (B7/B7M,

B16, B8/B8M/B8M2-Class2), A320 (L7/L7M), and A453 (660 Gr.C/D). Unless these studs, refer to

equipment installation manual or advice discipline engineer prior to work.

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ISO 9000

4. WORK FLOW DIAGRAM

Stud bolt removal Para. 6

Flange, bolt and gasket Inspection Para. 7

Flange installation and Alignment Para. 8 Tightening Method Manual Tightening Para. 9 Torque Tightening Para. 10 Bolt Tensioning Para. 11 Quality Assurance Para. 12 Complete

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ISO 9000

5. SAFETY PROCEDURE

Only properly trained personnel shall use any machinery or mechanical equipment for tightening stud bolts. Incorrectly using hydraulic bolt tightening/tensioning type equipment i.e. Hydratight® could result in a crushing injury. Correct PPE must be worn at all time. When breaking flanges, the joint shall always be broken in the direction facing away from personnel.

6. STUD BOLT REMOVAL PROCEDURE

6.1 Remove stud bolts and nuts. Using the tightening sequence in Aappendix A for loosening the studs. Usually half of the load is removed from the bolt in the first pass. This ensures no overloading of the remaining few bolts left in the flange towards the end of the loosening procedure. Completely loosen all nuts on the second pass, but do not remove bolts until the seal has been broken.

6.2 Remove old gasket and dispose of correctly. Gaskets shall not be re-used under any circumstance. 6.3 Install flange face protection covers if applicable.

7. INSPECTION OF FLANGE, STUD BOLT AND GASKET BEFORE INSTALLATION

PROCEDURE

7.1 Remove flange covers (if in place) and clean flange face. Check flange face to ensure it is clear, clean and undamaged. Report any damage to the supervisor.

- Inspect the mating flanges for dirt, mechanical damage, paint and corrosion. Use a suitable solvent to clean the surfaces.

- The contact area of the flanges should be flat (not convex or concave), free from excessive pitting, radial tool marks and scratches.

- Tears or scratches on gasket face deeper than 0.2 mm and covering more than 30% width in

radius projected length (all flange type) shall be re-machined or replaced.

- Inspect the back of the flange at the nut seating area. This area should be smooth finished and parallel to the flange face (within the ASME requirements).

- For less severe damage, depending on mechanical supervisor or inspector judgement, silicone compound (e.g. Locktite® 5920, etc.) can be used for fill the damage area.

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ISO 9000

Figure 3 Radial Projected Length (RPL) serrated gasket face damage

7.2 Ensure the stud bolts being used are correct. Refer to the isometric or piping class for correct bolt and nut size and length. The diagram below shows how to identify the type of bolt and nut.

- Inspect the studs and nuts. They should be free of dirt and corrosion. The studs should be straight and the threads free from nicks, burrs, and chips. Recommend to compare with the new stud, threads of the used one and the new one should be mesh equally. Then, run the nut on the stud and shake them whether the nut can be loosen.

- Apply a suitable lubricant (Locktite® Nickel Anti Seize or Molycote® P-37) to the threads and the face of the nut that contacts the flange. Apply the lubricant in a consistent manner as a thin, uniform coating (avoid "lumps" of lubricant as this may reduce the efficiency). Ensure lubricant does not contaminate either flange or gasket faces.

- Run the nuts or bolts down by hand. This gives an indication that no thread defect.

955 2H JS Nut Material Unique T raceable Batch Number Nut Manufacturer Identification B7

Stud Bolt Material Grade B16

B8 (B8 Class 2) B8M (B8M Class 1) B8M (B8M Class 2)

NUT STUD BOLT

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ISO 9000

7.3 Ensure gasket is correct to the isometric or piping class specifications. Inspect the gasket material for

possible defects such as bonds and creases.

8. FLANGE INSTALLATION PROCEDURE

8.1 Number each stud hole with the bolting sequence as outlined in Appendix A. “Stud Tightening Pattern”. 8.2 The flanges shall be lined up and aligned properly. The bolt holes should match so the studs can be

inserted freely (without force).

- Before taking alignment measurement, a gasket and 25% of bolts (with at least four) shall be inserted.

- Use four studs in positions 1, 2, 3 and 4 as centering guides for the gasket. Careful centering of the gasket and take care when bringing the flanges together to ensure that the gasket is not pinched or otherwise damage.

- The bolts then shall be fastened by using manual spanners (without force) to take out the free slack for ensuring the real misalignment can be measured.

- Acceptance criteria for flange face misalignment are described as below;  Lateral alignment (offset of the aligned flange centerlines)

The free insertion of the bolts is generally sufficient to demonstrate acceptable alignment. It may also be measured (if necessary) at the locations 90° apart around the flange

circumference. The measured lateral misalignment shall not exceed the following values;

Table 1 Lateral maximum misalignment for all flanges

Flange Diameter Maximum Misalignment

Piping ≤ 4” 2 mm

Piping > 4” 3 mm

Pipe to Rotating Equipment 0.3 mm/ 100mm of flange OD

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ISO 9000

 Parallelism (flange faces alignment) should be measured at the outside rim of the flange by

checking the distance between the mating faces of the pre-assembled joint using filler gauge. The difference between the measurements shall not exceed:

a) Pipe mating flanges:

The allowable misalignment is defined as a ratio of distance between mating faces per flange outside diameter. The misalignment shall not exceed the table2. Table 3 gives these values computed for the flange rim outside diameter.

Table 2 Parallelism maximum misalignment of piping, accessory and static equipment flanges

Flange Diameter Maximum Misalignment

<12” No control

12” to 24” See table 3 Left)

> 24” See table 2 Right)

Table 3 Computed maximum misalignment for Left) flange 12-24 inches; Right) flange larger than 24 inches

Pre-assembled joint (mm) Pre-assembled joint (mm)

size Rating size ASME B16.47, series B

DN 150 300 600 900 1500 2500 DN 150 300 600 900 1/2 0.22 0.24 0.24 0.30 0.30 0.33 26 2.03 2.27 2.37 2.54 3/4 0.25 0.29 0.29 0.33 0.33 0.35 28 2.03 2.26 2.35 2.56 1 0.27 0.31 0.31 0.37 0.37 0.40 30 2.01 2.23 2.31 2.51 1 1/2 0.32 0.39 0.39 0.44 0.44 0.51 32 2.03 2.20 2.28 2.52 2 0.38 0.41 0.41 0.54 0.54 0.59 34 2.01 2.19 2.26 2.53 80 0.48 0.52 0.52 0.60 0.67 0.76 36 2.00 2.17 2.25 2.50 4 0.57 0.64 0.68 0.73 0.78 0.89 38 2.02 1.99 6 0.70 0.79 0.89 0.95 0.98 1.21 40 2.01 2.00 8 0.86 0.95 1.05 1.17 1.21 1.38 42 1.97 1.98 10 1.02 1.11 1.27 1.37 1.46 1.68 44 1.97 1.98 12 1.21 1.30 1.40 1.52 1.68 1.91 46 1.96 1.99 14 1.33 1.46 1.51 1.60 1.87 48 1.95 1.97 16 1.49 1.62 1.71 1.76 2.06 50 1.95 1.97 18 1.59 1.78 1.86 1.97 2.29 20 1.75 1.94 2.03 2.14 2.46 24 2.03 2.29 2.35 2.60

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ISO 9000

b) Flanged accessories:

Accessories are flanged items which are rigid in themselves e.g. valves, strainers, etc. The misalignment shall not exceed 2.5 mm/m or values in table3 in any flange size.

c) Pipe-Static Equipment & Cover Part on Static Equipment

The misalignment shall not exceed 0.50_{(8.7 mm/m) or values in table4 in any flange size.}

Table 4 Computed maximum misalignment for static equipment Pre-assembled joint (mm) size Rating DN 150 300 600 900 1500 2500 1/2 0.77 0.84 0.84 1.04 1.04 1.15 3/4 0.87 1.01 1.01 1.15 1.15 1.22 1 0.94 1.08 1.08 1.29 1.29 1.39 1 1/2 1.11 1.36 1.36 1.53 1.53 1.77 2 1.32 1.43 1.43 1.88 1.88 2.05 80 1.67 1.81 1.81 2.09 2.33 2.64 4 1.98 2.23 2.37 2.54 2.71 3.10 6 2.44 2.75 3.10 3.31 3.41 4.21 8 2.99 3.31 3.65 4.07 4.21 4.80 10 3.55 3.86 4.42 4.77 5.08 5.85 12 4.21 4.52 4.87 5.29 5.85 6.65 14 4.63 5.08 5.25 5.57 6.51 16 5.19 5.64 5.95 6.12 7.17 18 5.53 6.19 6.47 6.86 7.97 20 6.09 6.75 7.06 7.45 8.56 24 7.06 7.97 8.18 9.05 10.16

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ISO 9000

d) Pipe-Rotating Equipment

The misalignment shall not exceed the following table:

Table 5 Parallelism maximum misalignment for rotating equipment

Flange Diameter Maximum Misalignment at OD of flange

< 12” 0.2 mm

12” to 24” 0.3 mm

≥ 24” 0.5 mm

Figure 5 Schematic diagram of lateral alignment and parallelism

8.3 Insert the balance of the studs.

8.4 Finger tighten all studs and nuts. Centre studs between nuts so an equal number of threads project at each end. Generally, 3 threads should be exposed beyond the end of the nut. The nut shall never be below flush with the end of the bolt. When tensioning is required, a threaded length of one (1) times bolt diameter should protrude at the end where the bolt tensioning machine is to be placed.

8.5 Then, the bolt-gasket-flange assembly are ready for be tightened. See appendix B to evaluate the applicable tightening method for that equipment.

Parallelism Lateral Alignment

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ISO 9000

9. MANUAL TIGHTENING PROCEDURE

9.1 The bolts should be tightened in accordance with the star pattern in Appendix A, developing the load in two stages.

9.2 1st_{Stage, apply approximately 50% of final tightening.}

9.3 2nd_{Stage, final pass, apply torque to 100% of final tightening.}

9.4 Make a second final pass but this time, change the sequence by doing the nuts right next to each other either in a clockwise or counter-clockwise direction

10. STUD BOLT TORQUE TIGHTENING

10.1 Generally, bolt stresses to be applied for most applications in refinery involving A193 (B7/B7M, B16,

B8/B8M/B8M2-Class2), A320 (L7/L7M), and A453 (660 Gr.C/D) bolts should be higher than

minimum require seating stress of gasket to ensure “NO LEAK” condition. Bolt torque values for the above stresses are tabulated in Appendix C. Unless using these studs, refer to equipment installation manual or advice discipline engineer prior to work.

10.2 Before inserting stud bolts ensure they are lubricated where the nuts run on the threads and also on the face of the flange where the flange and nut mate to minimize friction effect.

10.3 Where applicable; for bolt sizes 1 inch and smaller, a manual torque wrench may be used. For larger bolts, a suitable hydraulic torque wrench should be used.

10.4 Tighten the stud in 3 passes. Make the 1st_{, 2}nd_{and final pass respectively following the tightening}

sequence from Appendix A. Find the appropriate torque value of each pass in Appendix C.

10.5 Make a second final pass to ensure the tightness but this time, change the sequence by doing the nuts right next to each other either in a clockwise or counter-clockwise direction.

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ISO 9000

11. STUD BOLT TENSIOINING

11.1 Generally, bolt stresses to be applied for most applications involving A193 (B7/B7M, B16,

B8/B8M/B8M2-Class2), A320 (L7/L7M), and A453 (660 Gr.C/D) bolts should be higher than

minimum require seating stress of gasket to ensure “NO LEAK” condition (see Appendix C). The applied pressure shall be in accordance with the machine manufacturer’s pressure setting chart which is depended on the size of tensioning head used. Unless these studs, refer to equipment installation manual or advice discipline engineer prior to work.

11.2 The responsibility for Quality Control during bolt tensioning lies on the bolt tensioning contractor and Thaioil supervisor. Only contractors with a QA system approved by Thaioil Mechanical Maintenance Manager shall be used.

12. QUALITY ASSURANCE

12.1 Manual torque wrenches and the pressure gauges of hydraulic torque equipment shall be calibrated at least every six (6) months (sooner if required by the equipment manufacturer) and shall be

appropriately tagged to indicate when the calibration expires.

12.2 The responsible mechanical supervisor is responsible for all bolt tightening methodology quality assurance.

13. TRAINING/COMPETENCE

All supervisors and tradesman tightening flange joints shall be trained in the content of this procedure and their competence shall be verified by Thaioil mechanical supervisor prior to work execution.

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ISO 9000

14. REFERENCE DOCUMENT

The following Codes, Standards, and Specifications apply to this specification. When an edition date is not indicated for a code or standard. The latest edition and addendum in force at time of issue of this

specification shall apply.

American National Standards Institute (ANSI)

ASME/ANSI B1.1 Unified Screw Threads

ASME/ANSI B16.5 Pipe Flanges and Flanged Fittings NPS 1/2 Through NPS 24

ASME/ANSI B16.47 Large Diameter Steel Flanges NPS 26 Through NPS 60 (series B)

ASME/ANSI B31.3 Pressure Piping

ASME/ANSI B31.1 Chemical Plant and Petroleum Refinery Piping

American Society of Mechanical Engineers (ASME)

B & PV Code Section VIII Div1 Pressure Vessels Code for Pressure Piping TEMA STANDARD

TEMA TEMA 8th_{Edition STD of The Tubular Exchanger}

DEP STANDARD

DEP 31.29.00.10 Installation of Rotating Equipment

DEP 31.38.01.11-Gen Piping – General Requirements

DEP 70.08.10.11-Gen Mechanical Maintenance Equipments, Tools and Bolt Tensioning

THAIOIL DOCUMENT

ENSD-QFR-08 Inspection Duty Certificate

15. ATTACHMENT

15.1 Appendix A Stud Tightening Pattern

15.2 Appendix B Bolt Torque Tightening/Tensioning Selection Matrix