Iranian Classification Society Rules

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SECTION 6 Hoisting, Lifting, Rotating and Pipe Handling Systems


601. General

Requirements of this Section are to apply to th followings

(1) Derricks

(2) Hoisting system

(3) Lifting system

(4) BOP handling crane

(5) Pipe handling system

(6) Riser handling system

(7) Rotary equipment

(8) Miscellaneous system


602. Derricks


1. General

(1) Except as provided below, the design and fabrication of drilling derricks/masts are to be in ac- cordance with API Spec 4F, the Rules and the additional requirements of this Article.

(2) The following derrick/mast structural components are considered to be primary structure mem- bers specified in accordance with the Ch 3 of the Rules.

(A) Upper section: crown shaft, main crown beam and water table beams

(B) Lower section: legs, "V" door beams, shoes and girths

(C) Main load path structural components

(3) Materials are to be in accordance with Ch 3, Sec 1.

(4) Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.

(5) Complete Data Book, as specified in Annex A-A.3 SR3 of API Spec 4F, is to be provided for the Surveyor review.

2. Design loads

For structural design of the derrick, design loads, definition of forces and loads, and applicable loading conditions are to be in accordance with API Spec 4F, and as specified below:

(1) Structure failure consequences are to be categorized as medium or higher, as defined Spec 4F for the Structural Safety Level

(2) The derrick design is to consider both fixed and pinned boundary conditions.

(3) For fixed boundary condition, the Society allows a 20% increase in allowable stresses,

in API


as pro-


Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015 53

(4)


image

vided in API Spec 4F.

The Owner is required to specify the geographic region of operation, the static loads (dead weight, hook load, static rotary load, fluid load, setback loads, etc.) and dynamic loads (inertial load, dynamic amplification, erection, transportation, wind, transit, motion, acceleration, seismic, etc.) on the derrick, as required in API Spec 4F. Additionally, the following loads are also to be given consideration.

(A) The accumulation of ice and snow on a structure in increasing its dead load.

(B) The wind-induced load is to be included in the design analysis of the derrick structure and is to consider the following.

(a) The use of wind speeds higher than those provided in API Spec 4F, where required by the Owner, for regions not specified within API Spec 4F, KS B ISO 19901-1, or API Bull 2INT-MET.

mÕsec

(b) tTrahnesimt incoimnduimtiownsindis vneolotcittoy fboer ulensrsesthriacnted36offshore (s7e0rvkincoetsf)o.r Faollr hnosrtmasltrudctruilrleinsg otahnedr

than mobile offshore drilling units, such as production unit or fixed structure, the transit conditions are to be in compliance with Rules for the Classification of Fixed Offshore Structures.


(c)

mÕsec

nFotr tuonibtse utnarkeesntrilcetsesd tshearnvic5e1,.4the wind(10s0pekendotsto).

be considered in the survival case is

When other static or dynamic loading conditions are proposed by the Owner/Operator,

(d) technical justification in accordance with Ch 1, 103. is to be applied, on a case-by-case basis.


(C) The use of a higher rated setback, where required by the operational demands of the Owner.

(D) For dynamic loading due to motion of the hull, all motion information is to be provided, as specified below, by the owner or designer as specified in API Spec 4F for installation,

transit, operation, survival condition of the floating units, as applicable. The above conditions

are not to be less than those specified in the Rules, Rules for the Classification of Steel Ships and Rules for the Classification of Fixed Offshore Structures.

(a) For the calculation of dynamic loading induced by floating hull motion, the vertical dis-

tance and the horizontal distance, where applicable, between the center of flotation of the host drilling unit and the center of gravity of the derrick are to be provided by the Owner to the derrick designer and are to be used in the calculations.

(b) The horizontal distance is to be considered in addition to the vertical distance in the transit condition for self-elevating drilling units.

(c) If motion analysis for floating structure is performed, the appropriate acceleration data from the analysis are to be provided for the Society's review.

3. Live loads for local structure and arrangements

(1) The arrangement of members is to allow the free drainage of water from the structure.

(2) The following are the minimum vertical live loads that are to be considered in the design of walkways.

(A) General traffic areas: 4,500 NÕmĪ

(B) Working platforms: 9,000 NÕmĪ

(C) Storage areas: 13,000 NÕmĪ

(3) It is to be noted that various national and international regulatory bodies have requirements for

the loading, arrangement and construction of local structure such as guardrails, ladders and

walkways.

4. Allowable stresses

(1) To prevent excessive stresses in structural members and connections, or buckling, reference is to be made to the allowable stress limits given in the AISC or other recognized standard.

(2) The extent to which fatigue has been considered in design is to be indicated in submitted de-

sign documentation.

(3) For allowable stresses in plate structures, refer to Par 5.

(4) Consideration is to be given in stress calculations to ensure that maximum stress loads include "Jarring Procedures".

5. Equivalent stress criteria for plate structures

For plate structures, members may be designed according to the equivalent stress criterion, where the equivalent stress is obtained from Ch 3, 410. of the Rules.


54 Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015

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6. Bolted connections

(1) Where bolted connections are used in the derrick, the design documentation, including torqueing procedures, is to be submitted for the Society's review.

(2) Bolted connections in the main load path such as on upper mast, foundation, and crown, etc.

are to be provided with secondary retention or locking mechanism.

(3) Bolted connection designs are to consider the following.

(A) Fatigue

(B) Design loading in accordance with Par 2.

(C) Allowable stress in accordance with AISC

(4) Bolt torqueing procedures are to include, but not limited to, sequencing, torque loads.

(5) Bolt materials are to be selected with consideration to stress corrosion cracking, fatigue, marine environment.


603.


1.

Hoisting system


The hoisting system typically consists of crown block with its support beams, traveling block with its guide track and dolly, sheaves for crown block and traveling block, deadline anchors, draw- works, drilling hook, drilling line, drilling elevators, hydraulic cylinders for overhead lifting, pipe racking, power swivel, bells, and rotary swivel, wire rope and hoisting equipment gears.


2. Drawworks

(1) Drawworks are to be provided with primary and emergency braking systems. Both braking sys- tems are to be designed for full rated load at rated speed.

(2) Drawworks emergency brakes are to be of a fail-safe design.

(3) Anti-crown collision/upper limits, and lower limits are to be provided.

(4)


(5)

Zone management principle is to be followed for all hoisting activity in order to provide addi- tional safety to personnel and collision safeguard associated with drilling activities. Zone man- agement consideration can be any one or combinations of the following.

(A) Markings

(B) Strobe light

(C) Proximity sensors

(D) Alarms

Drawworks control is to be provided with deceleration parameters for upper and lower limits for the traveling block to safely stopping the load.

(6) Drawworks construction is to comply with API Spec 7F for chains and sprockets.

(7) All mechanical load-bearing components are to be in compliance with API Spec 7K.

(8)


(9)

The mechanical coupling between the drawworks drum and the electromagnetic brake is to be provided with a system to prevent unintentional disengagement.

Drawworks auxiliary brakes and all other electrical power and control systems are to be suit- able for the intended hazardous area.

(10) For hydrodynamic brake systems, detailed drawings and supporting calculations proving that

the proposed braking system is as effective as other drawworks braking systems are to be sub- mitted for the Society's review.

(11) Electromagnetic dynamic brake systems are to be arranged to prevent inadvertent failure of the drawworks to suspend the derrick overhead load.

(12) Electromagnetic systems are to include the following provisions.

(A) Cooling water temperature and flow indicators and alarms for abnormal or upset conditions.

(B) An automatically activated emergency stop system capable of applying full braking torque to stop and lower the full rated load by the application of friction brake or by connection of the electromagnetic brake to an alternative power supply (backup battery or UPS).

(C) A system that monitors either electrical faults within the system or the kinetic energy of the traveling block arranged to actuate the emergency stop system. Where a fault monitoring system is provided, provisions are to include the following:

(a) System must be provided with emergency power source.

(b) Brake coil current

(c) Monitors that initiate emergency stop upon detection of a preset brake coil current or a brake coil current varying in proportion to the driller’s control lever position

(d) Brake coil leakage current detector

(e) Audible and visual alarms at driller's control panel to indicate when the limiting parame-

Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015 55

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ters of the auxiliary brake have been reached or when the emergency stop system has been activated.

(f) In the case of AC motors using variable frequency drives for braking, an abnormality in

any of the connected drives is to alarm to the driller's control station.

(D) A manual emergency stop button is to be installed within reach of the driller.

(13) Electrical systems are to be in accordance with Ch 6, Sec 1.

(14) Control systems are to be in accordance with Ch 6, Sec 2.

3. Power swivels, rotary swivel, and top drives

(1) Major mechanical load-bearing components are to be in accordance with Par 5.

(2) Pressure vessels are to be in accordance with Sec 8.

(3) Electrical systems are to be in accordance with Ch 6, Sec 1.

(4) Control systems are to be in accordance with Ch 6, Sec 2.

(5) Piping systems are to be in accordance with Ch 5.

(6) Gears and couplings are to comply with AGMA or equivalent and be suitable for their intended service in terms of maximum power rating, service life and minimum operating temperature.

4. Safety devices and instrumentation

(1) The hoisting equipment is to have a weight indicator installed and the display is to be easily read from the driller's console.

(2) A safety device is to be installed to prevent the traveling block from contacting the crown block. This safety device is to be designed to be fail-safe.

(3) Testing intervals for the safety devices are to be agreed upon by the Owner but is not to be

less frequent than as specified by the drawworks manufacturer.

(4) If override to the uppermost limit of travel is provided, it is to be part of the testing, accordingly.

5. Hoisting equipment specific requirements

(1) Crown block, sheaves, traveling block, hook, rotary swivel, tubular goods elevators and other overhead hoisting equipment are to be designed in compliance with API Spec 8A or Spec 8C and the additional requirements of this Annex.

(2) The results of the prototype load test required in API Spec 8A or Spec 8C along with design calculations for the component tested are to be submitted.

(3)

Materials for mechanical load-bearing or pressure-retaining equipment are to be in accordance

with the material traceability and toughness requirements of Ch 3, Sec 1.

(4) Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.

(5) Wire rope is to be designed in compliance with API Spec 9A.

(6)

Main load-bearing weld connections are to be full penetration. Where partial-penetration welds are utilized, validation through design and fatigue analyses, manufacturing process and procedure qualifications are required.

(7) Lighting fixtures and other equipment installed in the derrick are to be secured against vibration to prevent falling.

(8)


(9)

Gears having a rated power of 100 kW and over and that are part of the critical load path are

to be designed, constructed, certified and installed in accordance with AGMA or equivalent. The Society is to review the design and the gears are to be constructed under the attendance of the Surveyor.

Gears having a rated power of 100 kW and over, but not part of the critical load path, and all gears having a rated power of less than 100 kW are to be designed, constructed and equipped in accordance with recognized commercial and marine practice. Acceptance of such gears will be based on manufacturer's declaration stating compliance with a recognized standard, ver- ification of gear nameplate data and subject to a satisfactory performance test after installation conducted in the presence of the Surveyor.


604.


1.

Lifting systems


The lifting system typically consists of cranes, base-mounted winches, personnel lifting systems and other lifting systems associated with drilling activities.


2. Cranes

(1) Cranes are to be Spec 2C or Pt 9,


designed, constructed, and tested in accordance with the requirements of API

Ch 2, Sec 4 of Rules for the Classification of Steel Ships.


56 Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015

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(2) When alternate codes or standards are proposed, comparative analyses are to be provided to demonstrate an equivalent level of safety to the recognized standards as listed in this Annex and to be performed in accordance Ch 1, Sec 1, 103.

(3) Design loads of the crane winches are to be the maximum rope tension based on the design loading or the load created by dynamic braking, in accordance with the above design code. In either case, the distribution of loading from the reeving system is to be taken into account.

(4) Allowable stresses are to be in accordance with AISC or other recognized standard.

(5) Drums and brakes are to be in accordance with API Spec 2C or Pt 9, Ch 2, 702. 2 of

Rules for the Classification of Steel Ships.

(6) Wire ropes are to be in accordance with API Spec 2C and API Spec 9A.

(7) Design loads of the crane cylinders are to be the loads applied by the crane boom. Allowable stresses or minimum scantlings are to be in accordance with Pt 9, Ch 2 of Rules for the Classification of Steel Ships. or other recognized standard.

(8) Zone management principle is to be followed for all lifting activity in order to provide addi- tional safety to personnel and collision safeguard associated with drilling activities.

(9) Electrical systems are to be in accordance with Ch 6, Sec 1.

(10) Control systems are to be in accordance with Ch 6, Sec 2.

(11) Pressure vessels are to be in accordance with Sec 8.

(12) Piping systems are to be in accordance with Ch 5.

(13) Materials are to be in accordance with Ch 3, Sec 1.

(14) Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.

3. Base-mounted winches and other lifting devices

(1) Design loads considered in the design analyses are to include the following.

(A) Recommended single rope tension at specified speed, drum size and layers of wire rope

(B) Maximum load created by dynamic braking

(C) Dynamics created by drilling unit motion

(2) Design standards and factors of safety

(A) Bases and other structural steel components are to be designed in accordance with AISC or other recognized standard. Allowable stress for bending, tension, shear and buckling are to be as specified herein.

(B) Factors of safety for wire rope, drums, shafts and other parts are as follows.

(a) Wire rope for lifting application is to be rated in accordance with API Spec 2C.

(b) Load-carrying member allowable stress is to be no greater than the following.

 = 0.8

= 0.65

ſſᾏᾮ ſſᾏᾮ

(for flat members)

(for curved members)

 = 0.75

 = 0.3(

ſſ ( ſſ < 0.7 ſſ )

ſſ + ſſ ) ( ſſ > 0.7 ſſ )

 = 0.5773 Â

where

 = allowable stress for buckling

 = allowable stress in tension or compression

 = allowable shear stress ſſ = material yield stress ſſ = material ultimate stress

ſſᾏᾮ

= critical buckling stress

(c) In addition, any combined stresses are not to exceed ſſ .

(3) Materials and fabrication

(A) All mechanical parts where failure could terminate the load-carrying capabilities of the sys-

tems are to be made of steel.

(B) Use of ductile iron for gears and drum and the use of aluminum for fabrication will be specially considered.

(C) Materials are to be in accordance with Ch 3, Sec 1.

(D) Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.

(4) Drums

(A) The rope at its end is to be secured to the drum in such a manner that will not damage


Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015 57

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any part of the rope and to have such a length that not less than 3 complete turns in case of an ungrooved drum, or 2 complete turns in case of a grooved drum are remaining on the drum when the complete working length of rope has been paid out.

(B) The drum end flange diameter is to have an allowance corresponding to not less than 2.5 times the rope diameter as measured from the outer rim of the outermost layer of ropes in service condition. However, where rope disengagement prevention system is provided or in case of single layer winding on the drum, this requirement may be dispensed with.

(C) The pitch circle diameter of drum is to be not less than 18 times the rope diameter.

(D) Materials are to be in accordance with Ch 3, Sec 1.

(E) Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.

(5) Wire ropes

(A) Wire ropes are to be constructed in accordance with a recognized standard applicable to the

intended service, such as API Spec 2C and API Spec 9A.

(B) Usage records such as ton-mile records are to be maintained and wire rope changed out in accordance with manufacturer's recommendations.

(C) Wire ropes used in non-manriding applications are to be replaced if damage exceeds manu- facturer's specifications for their rated capacity or if damage could affect smooth passage

through sheaves.

(6) Brakes

(A) The power operated braking system is to operate automatically upon loss of power or when the manoeuvring is returned to its neutral position.

(B) The braking system is to be able to exert a breaking torque 50 % in excess of the torque required when the safe working load is applied to the cargo handling appliances.

(C) Thermal capacity of the brakes is to be suitable for the intended services.

(D) Brake linings containing asbestos material are not to be used.

(E) Documentation and calculations for the braking affect of the AC motors are to be submitted when they are the only backup system to the disc brakes.

4. Personnel lifting devices

Manriding winches are to comply with the general requirements of this Chapter. In addition, the following minimum criteria are to be complied with.

(1) The personnel rated load is to be no greater than 20% of the load calculated in accordance

with Par 3.

(2) Control systems are, as a rule, to be of such design that controls automatically return to the neutral position when control operation by the operator is interrupted.

(3) Regardless of ton-miles, wire ropes used in manriding applications are to be replaced if phys- ical damage is visible.

(4) All brakes are to be fail-safe.

(5) Brakes are to set automatically upon loss of power or when the winch lever is returned to neutral.

(6) A secondary brake is to be provided to prevent the load from falling in the event of failure of

the primary automatic brake.

(7) A clutch capable of disengaging is not to be fitted.

(8) Devices are to be fitted to prevent the winch from overriding or underriding, and a secondary means of lowering personnel is to be provided in case of winch or power failure.

(9) Wire rope for personnel lifting devices is to be in accordance with API Spec 2C and API Spec 9A.

(10) Setting of upper limit is to provide at least a vertical clearance of six (6) feet from the upper block, and the lower limit is to be set so that the winch cannot be operated with number of

wraps less than specified in 2 (4).

(11) All winches are to be identified as "Manrider Only" and marked with their SWL.

(12) Electrical systems are to be in accordance with Ch 6, Sec 1.

(13) Control systems are to be in accordance with Ch 6, Sec 2.

5. Lifting attachments and pad eyes

(1) Design loads and test loads for lifting attachment are to be in accordance with the requirements of API Spec 2C and API RP 2A WSD, respectively.

(2) Allowable stresses are to be in accordance with the specified design code and standard.

6. Safety devices and instrumentation

(1) All winches are to be marked with the maximum permissible load allowed for the winch and


58 Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015

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its system components.

(2) Where pneumatic winches are provided, the air supply lines are to be sized to operate the winch at safe working loads.

(3) An air regulator and pressure relief valve, located upstream of the non-return valves, are to be provided to limit air supply pressure to the winch, and the supply lines serving the winches are to be fitted with appropriate non-return valves and water filters before the operating valves.


605. Pipe handling systems


1. General

(1) The pipe handling systems typically consists of elevators, finger boards, stabbing boards, iron roughnecks, cranes, winches, and wire ropes.

(2) Foundations and storage racks are to be designed to withstand the maximum anticipated setback load of the racked pipe, drill collars and other intended loads.

(3) All storage racks are to be designed to prevent drill collars, pipe and other tubulars from being

released from the rack. Racking stands are to have provision for drainage.

(4) Major mechanical load-bearing components are to be in accordance with 603. 5.

(5) Hydraulic and pneumatic cylinders are to be in accordance with Sec 8, 802.

(6) Mechanized pipe handling systems are to have their safety controls verified on computer-based racking systems.

(7) Indexing of all mechanical movement must be verified by operational testing. This procedure is

to be carried out in all available fingerboard configurations, and system safety verified.

(8) Cranes and winches are to be in accordance with 603.

(9) Zone management principle is to be provided to protect personnels and equipments from all pipe handling activity.

(10) All safety functions are to be provided with visual and audible indicators.

(11) Electrical systems are to be in accordance with Ch 6, Sec 1.

(12) Control systems are to be in accordance with Ch 6, Sec 2.

2. Stabbing boards

(1) Rails, masts, guides and runners

(A) The rails and masts supporting the stabbing board are to be securely attached to their sup- ports, designed so that they are unable to open under operating conditions and capable of supporting the stabbing board in the event of the operation of the safety gear.

(B) The guides and runners are to be designed so that in the event of a roller or wheel failure, the platform cannot become detached from the mast.

(C) Upper and lower limits are to be provided and tested before use.

(2) Controls and safety

(A) The controls are to be arranged to stop the platform if the raising and lowering handle is released.

(B) Two (2) independent locking devices are to be provided. One (1) locking device is to be engaged when the lifting handle is in neutral and the second is to engage upon failure of the hoisting system.

(C) Fail-safe upper and lower limit switches are to be provided, as applicable.

(D) All platforms are to be fitted with sufficient anchoring points for safety harnesses.

(E) A non-slip surface and adequate handrails, midrails and toe-plates are to be provided on the platform.

(F) The platform is to be fitted with a lock latch mechanism that secures it when it is not in

motion.

(G) Additionally, adequate safety gear of the progressive type is to be provided, and designed so that it will be engaged within free fall conditions.

(H) Where two-point operation is used, the operator station in the basket is to override the

remote.

(I) A safety override at the remote station is to be installed for use in the event that the work performing personnel are incapacitated.

(3) Hoisting

(A) Hoisting is to be arranged for both raising and lowering of the platform. The arrangement is not to be such that it is possible to lower the platform by brake only.

(B) Means of lowering the man to the drill floor must be provided that will function in case of failure of the normal hoisting mechanism.


Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015 59

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(C) A speed-controlling device is to be provided which is designed to prevent the raising and lowering of the platform at speeds in excess of the tripping speed.

(D) The factor of safety for rope or chain is not to be less than 10.

(E) If rack and pinion systems are used, they are to be designed so that the failure of either a rack or pinion will not cause the platform to fall.

(F) The hoisting system is to incorporate sufficient rope so that there are at least five (5) full

turns of rope remaining on the winding drum when the platform is at its maximum level.

(G) The equipment associated with the operation of the stabbing board is to be securely anch- ored to the derrick structure.

(H) The anchorages for rope or chain are to be designed such that they will not be adversely affected by corrosion.


606. Rotary system


1. The rotary system typically consists of master bushing and the rotary table, including its skid adapters and driving unit.


2. The rotary table and its components are to comply with the following requirements.

(1) All mechanical load-bearing components are to be in compliance API Spec 7K.

(2) Load-bearing beams are to be in accordance with Ch 3,

(3) Materials are to be in accordance with Ch 3, Sec 1.

Sec 1, 102.

(4) Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.

(5) The rotary table transmission and associated motor couplings and shafting are to comply with a

recognized standard and be suitable for the intended service in terms of maximum power and minimum operating temperature.

(6) Electrical systems are to be in accordance with Ch 6, Sec 1.

(7) Control systems are to be in accordance with Ch 6, Sec 2.


607.


1.

Miscellaneous equipment


Miscellaneous equipments in the drilling system could include manual tongs, horizontal BOP trans- porter/skidders, power slips, power tongs, catwalk, mechanical mousehole and any other handling

devices used to aid in the transfer of drilling tubulars and marine table and storage areas.


2. Major mechanical load-bearing components are to be in accordance

drilling riser between the rotary


with 603. 5.


3. Hydraulic and pneumatic cylinders are to be in accordance with Sec 8, 802.


4. Horizontal BOP transporters are to be designed with consideration of loads, inertia, stability, pulling requirements, etc.


5. All tongs are to be capable of being securely attached to the derrick mast or back-up post and anchored by appropriate means such as a wire rope line or stiff arm that will have a breaking strength greater than the force exerted by the tongs.


6. Safety lines on tongs are to be positioned in such a manner that the tongs cannot rotate beyond anticipated limits.


7. Power tong pressure systems are to be equipped with safety relief valves that are to be set no higher than the maximum working pressure of the system.


8. Suitable NDE on all drill pipe handling and auxiliary equipment are to be carried out on a regular basis and records maintained for review by the attending Surveyors.


9. Electrical systems are to be in accordance with Ch 6, Sec 1.


10. Control systems are to be in accordance with Ch 6, Sec 2.


11. Piping systems are to be in accordance with Ch 5.


12. Materials are to be in accordance with Ch 3, Sec 1.


13. Welding and non-destructive examination are to be in accordance with Ch 3, Sec 2.


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