OISD - GDN – 202

For Restricted Circulation

Inspection of Drilling

and

Work-over Rig Mast & Sub- Structure

Oil Industry Safety Directorate7th Floor, New Delhi House

27, Barakhamba MargNew Delhi-110001

OISD - GDN - 202

For Restricted Circulation

Inspection of Drilling and Work-over Rig Mast / Structure

Prepared by

Functional Committeeon

Inspection of Drilling and Work-over Rig Mast / Structure

Oil Industry Safety Directorate7th Floor, New Delhi House

27, Barakhamba MargNew Delhi-110001

FOREWORD

The Oil Industry in India is more than 100 years old. Because of various collaboration agreements, a variety of international codes, standards and practices have been in vogue. Standardisation in design philosophies and operating & maintenance practices at a national level was hardly in existence. This coupled with feed back from some serious accidents that occurred in the recent past in India and abroad, emphasised the need for the industry to review the existing state of art in designing, operating and maintaining oil and gas units.

With this in view, the Ministry of Petroleum and Natural Gas in 1986 constituted a Safety Council assisted by the Oil Industry Safety Directorate(OISD) staffed from within the industry in formulating and implementing a series of self regulatory measures aimed at removing obsolescence, standardising and upgrading the existing standards to ensure safe operations. Accordingly, OISD constituted a number of functional committees of experts nominated from the industry to draw up standards and guidelines on various subjects.The present standard on " Inspection of Drilling and Work-over Rig Mast / Structure" was prepared by the Functional Committee on " Inspection of Drilling and Work-over Rig Mast / Structure” This document is based on the accumulated knowledge and experience of industry members and the various national and international codes and practices.This standard is meant to be used as supplement and not as a replacement for existing codes and practices.It is hoped that provisions of this standard if implemented objectively, may go a long way to improve the safety and reduce accidents in Oil and Gas Industry. Users are cautioned that no standard can be a substitute for the judgement of responsible and experienced Drilling Engineers.

Suggestions are invited from the users after it is put into practice to improve the document further. Suggestions for amendments to this document should be addressed to the Coordinator, Oil Industry Safety Directorate, 7thFloor,New Delhi House, 27 – Barakhamba Marg, New Delhi - 110 001.

This standard in no way supercedes the statutory requirements of bodies like DGMS, CCE or any other Government Body which must be followed as applicable.

COMMITTEE FOR GUIDELINES ON" Inspection of Drilling and Work-over Rig Mast / Structure

-----------------------------------------------------------------------------------------------------------------------------NAME ORGANISATION POSITION IN

COMMITTEE----------------------------------------------------------------------------------------------------------------------------

S/SHRI

1. T H MAZUMDAR OIL LEADER

2. TAPAN RAY ONGC MEMBER

3. TRILOK SINGH ONGC MEMBER

4. N K GARG ONGC MEMBER

5. M K MANOCHA ONGC MEMBER

6. S R DAS OIL MEMBER

7. N YADAV ONGC MEMBER 8. JAYANT AHUJA OISD CO-ORDINATOR

----------------------------------------------------------------------------------------------------------------------------

CONTENTS

SECTION DESCRIPTION PAGE NO.

1. Introduct ion 1

2. Scope 1

3. Definit ion 1

4. Methods of Inspection 2

5. Methodology for NDT Inspection of Mast and Sub Structure 7

6. Inspection of Various Equipment / Accessories of Mast & sub-structure

8

7. Checklist Format 10

8. References 11

9. Annexure 12

1.0 INTRODUCTION

The safe operation of the Drilling and Work-over rig largely depends on the mast and sub-structure. The success of the drilling / work-over operation depend whether mast and sub-structure are meeting the maximum load criteria for which it is designed or not.. In order to fulfill this condition, it is necessary to inspect the Mast and sub-structure periodically at a defined interval so as to identify & correct the defects arising out of fatigue, wear and tear & other reasons.

Mast is a structural tower comprising of one or more sections assembled in horizontal position on the ground and then raised to vertical operating position. If the unit contains two or more sections, it may be telescoped or unfolded during the erection procedure. The telescopic type mast is mounted on carrier. The rig understructure is fabricated with I(Eye) beams and pipes of special steel structure.

Mast is subjected to compressive loading as the depth progresses. Besides this, mast is also subjected to tension with some lateral loading, shock loading and vibrations as a result of drilling / work-over operations. Due to this operation, mast is subjected to fatigue and may develop crack on the weld joints and heat affected zone of the parent metal of the mast. Environmental conditions also create corrosion problems on the members of the mast and sub-structure.

In order to facilitate the drilling or work-over operation , Mast is equipped with few other equipment / accessories like, crown block, Monkey board, Dead line anchor, Stabbing board, Top-man escape device, various sizes of sheaves & electrical fittings for lighting. That also require to be inspected periodically along-with mast & sub-structure, for its smooth operation as a whole.

Inspection of Mast and sub-structure is to be carried out in such a way that there is no damage to structure during inspection by way of fitting, fixtures etc., As such adoption of appropriate method of inspection is also important apart from its effectiveness in determining the extent of cracks etc.

Guidelines has been prepared keeping in view the simplicity and understandability for operating personnel as a ready reference in fields.

2.0 SCOPE

Guidelines covers the Inspection of mast and sub-structure of Drilling and Work-over rigs deployed in Onshore area.

3.0 DEFINITIONS

Crown block assembly: The stationery sheave or block assembly installed at top of a derrick or mast.

Derrick: A semi-permanent structure of a square or rectangular cross section having members that are latticed or trussed on all four sides . This unit is assembled in the vertical or operation position , as it includes no erection mechanism. It may or may not be guyed.

Design Load: That force or combination of forces which a structure is designed to withstand without exceeding the allowable stress in any member.

Erection Load: The load produced in the mast and its supporting structure during the raising and lowering operation , or the sub structure during its raising and lowering operation.

Guy line: A wire rope with one end attached to the derrick or mast assembly and the other end attached to a suitable anchor to provide structural and / or lateral support for a mast under design loading conditions.

Height of derrick and mast without guy lines: The minimum clear vertical distance from the top of the working floor to the bottom of the crown block support beams.

Height of mast with guy line: The minimum vertical distance from the ground to the bottom of the crown support beams.

Maximum rated static hook load: A load composed of the weight of the travelling equipment and a static load applied to the travelling block

Maximum rated wind velocity: The maximum rated wind velocity is the wind velocity the

derrick or the mast assembly is designed to resist against the force of the wind.

Racking platform / monkey board: A platform located at a distance above the working floor for laterally supporting the upper end of racked pipe.

Rated static rotary load: The maximum weight being supported by the rotary table support beams.

Rated setback load: The maximum weight of tubular goods which can be supported by the substructure in the setback area.

Reverse Engineering: Testing of material by analysing the chemical composition and structural analysis of original material.

Substructure: Any structure through which hook load, rotary load and / or setback load are transmitted.

4. METHODS OF INSPECTION

There are various methods of inspection but all methods begin with the most easy and practical method i.e. visual inspection. The visual inspection forms the base and also the sign post for the further action that may be required with regard to the structure under concern. Considering the typical operation of an onshore rig,

Inspection of mast and substructure is done visually and through non-destructive examination.

The prerequisite of inspection is that the inspecting personnel should have prior information of the highly stressed zones. In this regard it is pertinent to point out that all information with regard to design of the mast especially the calculation may be acquired from the rig manufacturers and kept with the rig. In the absence of this, the other alternative would be to prepare sketches of all the rig structures and carry out analysis for operational loads and during rig lifting phase. Entire set of all design and drawings pertaining to the rig should be available at the rig location to facilitate the inspecting agency.

4.1 VISUAL INSPECTION:

Visual examination is generally used to determine such things as the surface condition of the part, alignment of mating surfaces, shape or evidence of leaking. In addition, visual inspection is used to determine a composite material’s (translucent laminate) subsurface conditions. Visual inspection should include checks for the following points:

Condition of the members where paints and corrosive protection coating if any has been spoilt / damaged.

Damage on the members due to impact, dent, deformation etc.

Corrosion on the members. Visible surface cracks in members. Visible cracks in weld. Loosened nuts and bolts ( To be done on

weekly basis), in case of derrick structure.

Check the areas of maximum stress.

A detailed checklist format for visual inspection is placed at Annexure – I. This checklist must be verified and signed by the rig in-charge and maintained regularly at site for easy accessibility of inspecting agency. A careful study of this report is necessary before taking up any repair / maintenance job. Also history of all accidents and damages including repair must be systematically maintained at site.

4.2 NDT INSPECTION

NDT inspections are vital tools for assessing the health of the members of the drilling / work-over rig structure. These give us a clear-cut indication as to what may go wrong in future and may lead to any unsafe, undesirable and disastrous situation. If timely remedial actions are taken, efficiency and the reliability of the rig will increase and it will help to achieve the goal of total loss control.

Non destructive testing may be used to assess the existing condition of the members of the mast or sub-structure. It may be carried out for the damaged members / cracked welds and for measurement of reduced thickness / extent of cracks etc. NDT inspection may also be resorted to whenever visual inspection indicates visible

cracks or damage even before the scheduled inspection.

4.3 NDT TECHNIQUES AND THEIR ROLES IN FAILURE ANALYSIS

It is obvious that no single method can detect all defects in a material. This is where a proper appreciation of the various NDT methods help in determining the right combination, which would review all the flaws.

The different factors influencing the detect ability of defects by various NDT techniques are:(a) Human factors(b) Material factors(c) Product factors(d) Defect types

Duly taking into consideration all these factors, the minimum detectable defect sizes with various techniques (applicable to steel) are as given in Table 1 . From Table 1, it is evident that a smaller size defect can be detected by ultrasonic technique. The normal failure modes that occur in service for the welding constructions are fatigue, brittle behavior, creep and stress, corrosion. It may be noted that all these failure modes involve the extension of crack.

The principle of fracture mechanics, which defines the fracture behavior in a quantitative way, tells us that there is a critical size of defect, which leads to sudden failure. Because of the unexpected loading pattern that may occur in service, it may not be wise to allow a critical size defect in the structure, even if the design stress is lower than the critical stress for failure. Even if sizes of individual defects are much less than a minimum, there is a possibility of interaction among each other because of proximity and enhanced failure may occur. Through NDT inspections, it can be analyzed whether the defect is within the acceptable criteria based on which the components were originally designed.

There are four different types of NDT inspection for evolving the integrity and strength of a weld. Each of these methods constitutes only a particular domain of testing but in various combinations these are regarded as a powerful system of testing and evaluation of defects. These are primarily employed to detect flaws in the material present at the surface as well as the

interior. Since failures are often found to have originated from pre-existing flaws created during service by the action of stress and environment. NDT techniques serve as an active tool to reach to the root cause without destroying the valuable fracture features. The conventional NDT are categorized broadly into two groups.

a) Those detecting surface and subsurface flaws and

b) Those detecting internal flaws.

The following sections give a brief summary of the NDT techniques used during inspection of mast and sub-structure, along with their areas of effectiveness and limitations. Details of NDT techniques may be obtained from the relevant ASTM code mentioned in Chapter 8 .

All the inspection should be carried out by competent agency in view of critical nature of tests.

4.3.1 MAGNETIC PARTICLE INDUCTION (MPI)

This technique is used for ferromagnetic materials to detect surface and sub surface flaws. In this method, the component is magnetized by using a direct current or half wave rectified alternating current. In any homogeneous ferromagnetic material, a magnetic field forms an uninterrupted circuit from pole to pole through the material. However, in the presence of a discontinuity at or near the surface, the magnetic field is deflected and forms a leakage field. Detection of this leakage field forms the basis of this technique. Following test decision are to be considered during execution of MPI. Direction of magnetisation or Direction of

probability of discontinuity. To decide the equipment for best result Type of current – AC / DC/ HWDC Amount of level of current Examination medium- Dry / wet Technique of inspection – Continuous or

residual Demagnetisation ( If necessary)Magnetic field adequacy should be judged by using an ASTM magnetic field indicator. This test must be done at the starting and during inspection ( at an interval)Evaluation of results should be done as per acceptable criterions classified as True / False

TABLE 1

Minimum detectable defect size by various techniques

Method Surface defect (mm) Embedded defect (mm)

Visual 0.8 NilPenetrant 0.5 NilMagnetic particle inspection(MPI)

0.8 8.0

Radiography 0.5 0.3Ultrasonic testing(UT) 0.1 0.4

indication and subgrouped as Non – relevant & Relevant ( Linear & rounded) indications.

The areas of effective applications of magnetic particle inspections are as follows: -

Product / Process

Effective detection of

All ferro-magnetic materials casting , weldment, forging, assembly, ground and machined components

Surface/ sub surface cracks, grinding cracks, quenching cracks, stringer type non metallic inclusion, porosity , laps and folds

The main advantage of this method is that, it is reliable for detecting surface cracks specially very fine and shallow ones and there is no limitation as to size or shape of the part being tested. More over this method is effective through thin coatings of paint and other non-magnetic covering such as plating.

This method is simple, quick and inexpensive. The indications are clearly visible on the surface of the object. It is unaffected by possible deposits in the cracks e.g. oil, grease or other metals.Special preparation of the surface is not required before the measurement can be performed. The examination can be easily documented by means of a photograph or the tape impression etc. for the indication and actual mapping of the defect.

The limitations of this method are that applicability is confined only to ferromagnetic materials and it is not always possible to locate discontinuities, which lie deep below the surface. Certain object must be demagnetized before and after the examination. The item may be subjected to burn scars in connection with the current magnetization process. Experience and knowledge of the material is necessary in order to perform a correct interpretation of the results.

4.3.2 LIQUID PENETRANT EXAMINATION (LPE)

This method is applied to detect the discontinuity along the surface in solid and essentially non-porous materials. In this process, liquid penetrant seeps into various minute surface openings by capillary action. Moreover, indication of flaws is independent of size, configuration, internal structure or chemical composition of the material. The resolution of technique depends on the wetting characteristics of the liquid penetrant on the surface and can be as low as 0.1 micron. The basic process involves five steps:

i. Surface preparation ii. Penetration iii. Removal of excess penetrantiv. Development v. Inspection

Two methods are mainly adopted in Mast and sub - structure inspection depending on the type of penetrant:

4.3.2.1 DYE PENETRANT (DP)

The technique employs oil or water based penetrating liquid, which is applied over the surface of the component under study either by immersion or by means of a brush. Since the dye has low surface tension, it easily penetrates into very thin and light cracks. After sufficient soaking, the excess penetrant is removed from the surface and the component is cleaned with a suitable solvent (tri-chloro-ethylene or water). Selection of penetrant is very important in DP technique. A few important properties of good penetrant are high wetting properties, high capillarity, high fluiding low volatility, high visibility & inertness.

A thin layer of developer is applied uniformly over the surface. This absorbs the penetrant from small openings and spreads it over a large area as an indication of defects.

After a short time, indications appear in the developer which are wider than the defect and which therefore can be seen directly or

under ultraviolet light due to the enhancement of contrast which results between the penetrant and the developer.

The period of the time during which the penetrant is permitted to remain on the specimen is called penetration or Dwell time. This timing is very much critical . Normally tight cracks take longer time than the gross discontinuities. Dwell time is also affected by temperature of the specimen & the temp. of the penetrant.

Because the penetrant method works by allowing a liquid to enter a defect on the surface of a component and be drawn out to the surface afterwards, it is only possible to find defects, which are open to the surface. Foreign matter such as paint or oil must not be allowed to enter the defect as in such condition the penetrant is prevented from entering.

4.3.2.2 FLUORESCENT PENETRANT

This technique is similar to dye penetrant except for the use of a fluorescent fluid instead of a colour dye and examination under ultra violet light in a darkened enclosure. The resolution of this technique is superior to that of the dye penetrant.

4.4 RADIOGRAPHIC EXAMINATION

It is based on the principle that penetrating radiations are differentially absorbed by the material through which they pass. The absorption is primarily dependent on the energy spectrum of the radiation and the density and the thickness of the material. The radiation commonly used in radiography are X-rays, gamma rays, neutrons ray. During the inspection of rig, normally X-rays are used. The sharpness of the image is determined by the size of the target, the ratio of the source specimen and film specimen distances. Radiographic sensitivity is measured in terms of the minimum percentage of thickness of the components that corresponds to the observed change in the photographic

density of the radiograph. The size of the flaw is detected by using a penetrometer.Densitometer is to be used to measure the uniformity in density of radiographic plates. As per the code , the density of the plate should be within 3-6.The penetrometer or image image quality indicator gives fair idea on the quality of image. Different types of Penetrometer such as ASTM, DIN(ISO) and Hole type Penetrometer should be used as per the requirement and standards use of penetrometer helps in finding sensitivity i.e. size of the smallest defect detected by the system.While applying RT, sufficient care should be taken to avoid geometrical un-sharpness . To avoid this problem , SOD ( source object distance) and OFD9 Object to film distance) to be properly and judiciously decided.Acceptance criterions as per the standards should be followed considering linear indication & cluster indications etc.

The main areas of effective applications are given below:

Product / Process

Effective Detection of

Cast ingots, shaped castings, weldments

Internal discontinuities, e.g. Shrinkage, hot tears, cold shot, sponginess, porosity, cavities, cracks (which are not very tight), inclusions, segregation, mis-runs.

Assemblies Corrosion pits, mis-alignments, cracks (not very tight) and entrapment of dense materials.

The greatest advantage of radiography is that a permanent record of examined components can be preserved for future reference. However, it is essentially a slow and expensive method of inspection. Another major limitation is that if the differential absorption is below a certain limit, which cannot produce a readable density on the film, the information will not record on the film. Precisely for this reason, planer defects such as tight cracks, folds, laminations and de-bonds are not detected by radiography.

Radiography can be used with all materials and is independent of the magnetic and electrical properties of the material. It can be used in any situation when one wishes to see the interior of the object. It can be used to check an object for internal faults and construction defects. (e.g. faulty welding, soldering, riveting or adhesive bonding)

4.5 ULTRASONIC EXAMINATION

This method of testing consist of transmitting energy in the form of high frequency sound wave, longitudinal, horizontal and transverse (frequency 20000Hz) into the material under test. Ultrasonic energy is introduced into the specimen by means of a probe equipped with a transmitter and a receiver or by means of a separate transmitter and receiver through a coupling media such as water, glycerin, mineral oil or grease. The probe generates ultrasonic waves when an electrical field is applied to piezoelectric crystal such as quartz, barium titanate, etc. If flaws or discontinuities are present in the test material , an acustic mistch occurs and some or all of the ultrasonic energy is reflected back to the probe. The amplitude of back echo or reflected sound wave is related to the flaw characteristics such as crack. Void etc. and the time of travel through the specimen / test piece . Ultrasonic pulses reflected from the back surface of the material represents the total distance traveled, width, length or thickness depending upon the orientation of the test material. For most of the materials, the testing frequency of ultrasonic waves ranges between 1 and 15 MHz. The selection of test frequency depends upon the sensitivity and the sound penetration requirement. All frequencies will work equally well with the fine grained material. However high frequency should not be used in coarse grain material tends to scatter the energy.The main area of effective applications of ultrasonic testing are given below:Product / Process

Effective detection of

Forgings, extrusions, plates, sheets, bars, rods,

Detection of internal discontinuities such as cracks, bursts, laminations, inclusions, voids, de-

weldings bonding. Assemblies Stress corrosion cracking,

corrosion pits and fatigue cracks.

The main advantage of ultrasonic testing is the ability to get instantaneous results and a fast inspection rate. Its main limitations are complete dependence upon the competence and integrity of the operator to interpret the results, the difficulty in discriminating between different types of defects and the difficulty in detecting defects near the surface owing to the dead zone of the probe. Utmost care should be taken when the attenuation of the ultrasound is affected by heat treatment , material grain size and the modulus of elasticity.

5. METHODOLOGY FOR NDT INSPECTION OF MAST AND SUB STRUCTURE:

Proper evaluation methods and acceptable criterions should be followed as per specific standards during interpretation of results of NDT.

In case of any doubt or to avoid fictitious result, re examination of the area / object by the same technique or by any other technique should be carried out.

All electrical appliances / NDT equipment should be suitable for the technique for which the same is used.

The personnel conducting NDT jobs at site should be certified by a reputed agency.

5.1 Main mast- lower and upper section:

All the sections of the mast are taken into consideration from driller side, off driller side, draw works side and catwalk side.

Two UT readings are taken at each horizontal and diagonal member.

One UT reading is taken at each vertical member.

All the weld joints are cleaned by grinding or wire brushing or sand blasting to remove the scaling and rust and then are subjected to Dye penetration (DP) test / MPI.

5.2 Understructure and super structure:

Under structure is divided into main under structure and doghouse support structure.

Super structure is divided into catwalk side, draw works side and top & bottom beams.

Two UT readings (or every one-meter apart) are taken at each horizontal, vertical and diagonal member.

All the weld joints are cleaned by grinding or wire brushing or sand blasting to remove the scaling and rust and are subjected to DP test.

5.3 INSPECTION FREQUENCY

Visual inspection: Visual inspection of Mast and sub-structure should invariably be carried out after each rig dismantling.

NDT Inspection: It will be carried out initially after five years / depending upon the condition of rig ascertained after regular visual inspection and subsequently once in every 3-5 years .However in case any damage is suspected while carrying out operation, NDT inspection may be undertaken early as situation demands.In case of any operational mishap, NDT inspection may be undertaken prior to resumption of normal operation

5.4 Repair and Remedial Measures

All welds in load carrying mechanical and structural members, piping system and pressure boundary of pressure retaining components are to be made/repaired using approved welding procedure by qualified welders and are to be inspected utilizing approved procedures by qualified technicians. The following guidelines are adhered to while taking up repair / remedial actions based on visual / NDT inspection:

Repair, straighten or replace any bent or otherwise damaged load carrying members.

Damaged compression members should be replaced rather than be repaired by straightening.

Portable masts are generally made of high strength steels. So proper welding rods and welding technique is to be used while repair.

Always consult with manufacturer or refer manual for approval of materials and methods before proceeding with repairs reverse engineering process.

Avoid heating (except for welding ) while straightening a member as far as possible

Minor damages such as slight reduction in thickness due to corrosion or minor dent can be repaired using approved field methods.

6. INSPECTION OF VARIOUS EQUIPMENT / ACCESSORIES OF MAST AND SUB-STRUCTURE

In addition to mast and sub-structure, it is necessary to include the equipment of mast and sub-structure which covers Crown block, Deadline anchor, Monkey board, Stabbing board, Top man escape device, Sheaves and pins in the scope of inspection. The inspection methods / procedure and frequency of all equipment are given below:

6.1 METHODS OF INSPECTION

i. Daily /Weekly field inspection : Daily visual inspection should be made by the crew or supervisora) Cleaning : the component to be

inspected , should be kept clean by daily hosing and / brushing in order that the daily in operation visual inspection be effective

b) Disassembly: field disassembly is generally not practical and is not recommended unless a clean dust free location is available.

c) Inspection Procedure: Persons inspecting components of the equipment on a daily basis should look for cracks, loose fits or connections, elongation of parts and other signs of excessive wear or overloading. Any equipment found to show cracks, excessive wear etc. should be removed from service and sent to a suitably equipped shop for more detailed inspection and /repairs. Any defective components noticed must be marked with visible paint.

ii) Quarterly or during rig dismantling (which ever is later): The crew should do Quarterly inspection in the field with the supervisor.a) Cleaning: For the quarterly visual inspection all oil and grease should be removed from the surfaces to be inspected. b) Disassembly: field disassembly is generally not practical and is not recommended unless a clean dust free location is available.

iii) Disassembly inspection: Equipment should be taken to suitably equipped facilities and all parts checked for excessive wear and for the cracks or flaws both visual and by non destructive techniques (NDT) where in the opinion of the user excessive wear is noted, it is recommended that the matter be discussed with the manufacturer.a) Cleaning: before inspection all

foreign material such as dirt, paint, grease, oil, scale etc. should be removed from the equipment by suitable method.

b) Disassembly: equipment should be disassembled as much as necessary to permit NDT inspection.

c) Inspection Procedure:

Minor cracks or defects, may be removed without compromising safety of the equipment by grinding or fitting

preferably in consultation with manufacturer

Following removal of the defect, the part should be inspected by an appropriate NDT method to ensure that the defect has been completely removed.

6.2 Inspection procedure for various equipment:

6.2.1 Crown Block:

a) Check sheave groove for wear or cracks.

b) Checks pins and bearing for fit and lubrication.

c) Check mounting members for distortion.

6.2.2 Deadline Anchor:

a) To check wear of bronze wire line clamp inserts to secure cable grip without line damage.

b) To check wear of the grooves on the anchor drum.

c) To check the foundation bolts of the anchor with sub base.

d) To check deflection of Dead end sheave on load.

6.2.3 Monkey Board: a) Check for any damage in frame,

fingers, cracks in welds, walkway platforms & railings.

b) Check for any missing safety pins and pin connections.

6.2.4 Stabbing Board:

a) Check for the movement of rail, cracks in welds.

b) Check for any missing safety pins and pin connections.

6.2.5 Top-Man escape Device:

a) The track rope and haulage rope should be regularly cleaned and made free from any dust & rust

b) There should be no kink on any rope

c) All the unit’s pullies should be oiled and freely rotating.

d) The strands of the rope should not be damaged.

e) The turn buckles should be without damage and free from dust.

f) Also check whether the sheave rollers are free from dust rust and are rotating freely.

g) Check tension on haulage ropeh) A competent person should inspect

every part of the escape device at least every day.

i) The anchor at the ground should not be less than 45 mtrs. from the derrick / base of mast or equal to height of the mast from ground level , whichever is more.

j) Check the rotation of centrifugal brake when it is on the ground.

k) The centrifugal brake should be re-calibrated.

6.2.6 All sheaves: a) Check grooves of all the sheaves

attached with the mast.b) Check for the bearing( loose/ bad

condition)

6.2.7 Pins: Check for any crack. Cotter locks to

all pins should have to be ensured.

6.2.8 Inspection of Electrical Accessories of Mast

Electrical Lighting:Daily checks: Ensure that adequate lighting arrangement are available at derrick floor, driller’s console, Monkey board, dog house, BOP control, Cat walk, every place where persons are to work and every access/ escapes.

Earthing:a) Weekly Check: Ensure that

Equipment / mast are double earthed with appropriate G.I. strip / stranded flexible conductor.

b) Maintenance of earthing pit and its resistance measurement done at each new location during rig up and

after a period of 6 months whichever is earlier.

Cable Connection: Following points need to be checked during rig building and or qtrly. basis for its effectiveness:

a) Cables are laid down in the cable trenches as per IS 1255.

b) Cable connections have been provided with double compression glands in hazardous location.

c) Receptacles and plugs are in good condition.

d) Insulation of cable is in good condition.

e) Flame proof features (FLP) / increased safety features (as per zone classification) of junction boxes, lighting and cable connection viz. Air gap, glands etc are maintained in hazardous zones.

6.3 Frequency of Inspection

i. Daily / Weekly Field Inspection: Field inspection of drilling / work-over equipment in an operating condition should be made by crew or supervisor on a daily basis for all the equipment except crown block and stabbing board which is done on weekly basis.

ii. Quarterly or during rig dismantling (which ever is later): The crew should make a thorough on the job shut down inspection, with the supervisor once every three months/ or at the time of rig movement or more frequently if severe operative loads have been imposed.

iii. Disassembly inspection: Disassembly inspection of equipment should be done at suitably equipped facility based on the recommended practice of manufacture.

7. CHECK LIST FORMAT

Check list format to be used in visual inspection of mast and sub- structure is attached herewith at Annexure - I

8.0 REFERENCES

1. API Standards 4A,4D,4E & 4F2. MPI Methods:

I) ASME boiler and pressure vessel code section V, Article 7: “Magnetic particle examination”.

ii) ASTM E709: “Standard recommended practice for magnetic particle examination”. Acceptance criteria: Section VIII, Appendix 4, ASME Boiler and Pressure Vessel Code.

3. LP Methods:i) ASME boiler and pressure vessel code Section V Article 6: “Liquid penetrant examination”.

ii) ASTM E165: “Standard practice for Liquid Penetrant Inspection”.Acceptance criteria: ASME boiler and pressure vessel code, Section VIII, Division 1, Appendix 8, “ Methods for liquid penetrant examination”.ii) ANSI/AWS D1.1 “ Structural welding code”, 9.25 “Quality of welds”.

4. Radiographic Examination Method:i) ASME boiler and pressure vessel code section V Article2: “Radiographic Examination”.ii) ASTM E94: “Standard practice for radiographic testing”.iii) ASTM E446: “Standard reference radiographs for steel castings up to 2 in. in thickness”.iv) ASTM E186: “ Standard reference radiographs for heavy walled (2 to 4 ½ in. / 51 to 114 mm) steel casting”.v) ASTM E280: “ Standard reference radiographs for (4 ½ in. to 12 in. / 114 to 305 mm) steel castings”. Acceptance criteria: ASME boiler and pressure vessel code, Section VIII, Appendix 4, “ Rounded indication charts acceptance standard for radiographically determined rounded indications in welds”.

5. Ultrasonic Examination Methods: - i) ASME boiler and pressure vessel code Section V, Nondestructive testing,

Article 5, “UT examination methods for materials and fabrication”.ii) ASTM A388: “ Recommended practice for ultrasonic examination of heavy steel forging”.iii) ASTM E428: “ Standard recommended practice for fabrication and control of steel reference blocks used in Ultrasonic Inspection”.iv) ASTM A609: “ Specification for Ultrasonic Examination for carbon and low alloy steel castings”. Acceptance criteria:i) ASME boiler and pressure vessel code, Section VIII, Appendix 12, “Ultrasonic examination of welds (UT)”.ii) ANSI/AWS D1.1 Section 6, Part C, “Ultrasonic testing of groove welds”.

iv) API RP-2X “Ultrasonic examination of offshore structural fabrication and guidelines for qualification of ultrasonic technicians”.

Annexure ICHECK LIST OF VISUAL INSPECTION OF MAST & SUB- STRUCTURE

RIG OWNER’S NAME: ______________________________ RIG NO. __________________________

LOCATION _____________________________________ DATE __________________________

MAST/DERRICKIDENTIFICATION NO. ____________________________ SR. NO. __________________________

YEAR OF MANUFACTURE______________________________________________________________

RIG STANDING _______________________________________________________________________

INSPECTED BY ________________________________________________________________

________________________________________________________________

ACTIVE SERVICE YEARS_______________________________________________________________

DATE OF LAST INSPECTION____________________________________________________________

CUMULATIVE METERAGE DRILLED____________________________________________________

MAST / DERRICK NAME PLATE INFORMATION

a) MANUFACTURER’S NAME / ADDRESS

b) SERIAL NO.

c) HEIGHT IN FEET

d) MAX. STATIC HOOK LOAD WITH GUY LINES ,IF APPLICABLE FOR STATED NUMBER OF LINES TO TRAVELING BLOCK

e) MAXIMUM WIND RESISTANCE IN KNOTS , WITH GUY LINES IF APPLICABLE WITH GIVEN SETBACK

f) THE API STANDARD AND EDITION OF THE API STANDARD UNDER WHICH THE STRUCTURE WAS DESIGNED & MANUFACTURED

g) IS MANUFACTURERS GUYING DIAGRAM AVAILABLE

h) IS MANUFACTURERS LOAD DISTRIBUTION DIAGRAM AVAILABLE

SUB STRUCTURE NAME PLATE INFORMATION: -

a) MANUFACTURER’S NAME / ADDRESS:b) SERIAL NO.c) MAX. ROTARY TABLE SUPPORT BEAM

CAPACITY WITH OR WITHOUT RATED PIPE SET BACK:d) MAX. PIPE SET BACK CAPACITYe) API STANDARD AND EDITION OF THE API STANDARD UNDER WHICH THE

STRUCTURE WAS DESIGNED AND MANUFACTURED:

A) MAST / DERRICK:

I Crown Assembly

a) Sheaves

NO. _______ MAIN CLUSTER SHEAVE SIZE_________FAST LINE SHEAVE SIZE________________________

b) Condition

1. SHEAVES: WARPED______________________________OK___________________________GROOVE: WORN________________________________ OK___________________________

2. SPACERS OR SEALS: BAD_________________________OK___________________________GREASE FITTING: MISSING_______________________ OK___________________________

3. BEARINGS: LOOSE__________ BAD_______________OK___________________________

4. CROWN SAFETY PLATFORM: MINOR DAMAGE ___________________________________BADLY DAMAGED_______WELD CRACKS _________OK___________________________

5. CROWN HANDRAILS: MINOR DAMAGE __________________________________________BADLY DAMAGED_______WELD CRACKS _________OK___________________________

6. CROWN FRAME: BENT BEAM FLANGES _________________________________________BEAM WEBS BENT__________________CRACKED WELDS__________________________LOCATION_______________________________________OK___________________________

7. COMMENT: RUSTLY-------------------- NEEDS REPAIR------------------------------------------------NEEDS PAINTING------------------------- OTHER------------ -OK----------------------------------------

8. NUMBER OF VISIBLE MARKS APPLIED----------------------------------------------------------------

II Additional Sheave Assemblies:

NAME-----------------------------------------------------------------OK----------------------------------------NUMBER OF VISIBLE MARKS APPLIED----------------------------------------------------------------

III Crown Support Beams

BEAM FLANGES BENT---------------------------------------------------------------------------------------

BEAM WEBS BENT--------------------------------------------------------------------------------------------

CRACKED WELDS-------------------------------------------------OK----------------------------------------

NEEDS REPAIR-------------------------------------------------------------------------------------------------

NUMBER OF VISIBLE MARKS APPLIED----------------------------------------------------------------

IV Legsa) The following points are to be checked at Front Leg off Drillers Side, Front Leg On Drillers Side, Rear Leg Drillers Side, Rear Leg Off Drillers Side

BEND within Limit--------------------------------BEND Exceeding limit----------------------------------

NEEDS REPAIR------------------------------------------------------OK---------------------------------------PIN CONNECTION BAD-------------------------------------------OK---------------------------------------PIN HOLE BAD--------------------------------------------------------------------------------------------------CRACKED WELDS---------------------------------------------------------------------------------------------SAFETY PINS: MISSING-------------------------------------------

OK---------------------------------------

V. Spreaders (Back Panel trusser)

DAMAGE within limit---------------------DAMAGE exceeding limit-----------------------------------CRACKED WELDS --------------------------------------------------------------------------------------------NEEDS REPAIR-------------------------------------------------------OK--------------------------------------BOLT AND PIN: IMPROPER LENGTH--------------------------OK--------------------------------------SAFETY PINS: MISSING------------------------------------------ OK--------------------------------------BOLT AND PIN HOLES: OVAL-----------------------------------OK--------------------------------------

VI. Girts and Bracing (diagonal braces)

BENT---------------------------------------------------------------------------------------------------------------NUMBER BENT: SLIGHT ---------- NOS. BADLY------------NOS.-----------------------------------CRACKED WELDS --------------------------------------------------------------------------------------------NEEDS REPAIR--------------------------------------------------------OK-------------------------------------NO OF VISIBLE MARKS APPLIED-------------------------------------------------------------------------

VII. Feet or Pivots (Mast lugs)

DAMAGED-------------------------------------------------------------------------------------------------------CRACKED WELDS --------------------------------------------------------------------------------------------CORRODED------------------------------------------------------------------------------------------------------WORN HOLES------------------------------------WORN PINS----------------------------------------------NEEDS REPAIRS----------------------------------------------------------------------------------------------

VIII. A- Frame

a) LEGS: DAMAGED MEMBERS ---------------------------------------------------------------------------CRACKED WELDS---------------------------------------------------OK--------------------------------------

b) SPREADERS OR TRUSSES: DAMAGED MEMBERS-----------------------------------------------CRACKED WELDS---------------------------------------------------OK--------------------------------------c)UPPER CONNECTIONS: DAMAGED -------------------------------------------------------------------CRACKED WELDS---------------------------------------------------OK--------------------------------------d)LOWER CONNECTIONS:

CORRODED------------------------------------------------------------OK--------------------------------------

PIN CONNECTION: LOOSE----------------------------------------OK--------------------------------------PINHOLE: WORN-----------------------------------------------------OK-------------------------------------SAFETY PINS: MISSING--------------------------------------------OK--------------------------------------

IX. WORKING PLATFORMa) RACKING PLATFORM:FRAME: DAMAGED-------------------------------------------------OK--------------------------------------CRACKED WELDS --------------------------------------------------OK--------------------------------------PIN CONNECTION : WORN----------------------------------------OK-------------------------------------

SAFETY PINS: MISSING-----------------------------------------OK--------------------------------------FINGERS : DAMAGED---------------------------------------------OK-------------------------------------NEEDS REPAIR-------------------------------------------------------OK--------------------------------------

b) RACKING HANDLERS :

FRAME : DAMAGED------------------------------------------------OK--------------------------------------FINGERS : DAMAGED----------------------------------------------OK--------------------------------------BASKET : DAMAGED-----------------------------------------------OK--------------------------------------CRACKED WELDS --------------------------------------------------OK--------------------------------------

c)WORKING PLATFORM DAMAGED--------------------------OK--------------------------------------CRACKED WELDS --------------------------------------------------OK--------------------------------------

TUBING SUPPORT FRAME : DAMAGED----------------------OK--------------------------------------CONNECTIONS: DAMAGED--------------------------------------OK--------------------------------------CRACKED WELDS --------------------------------------------------OK--------------------------------------

HAND RAILS:DAMAGES:MINOR-----------------MAJOR-----------------------OK--------------------------------------CRACKED WELDS --------------------------------------------------OK--------------------------------------CONNECTIONS: NEED REPAIRS---------------------------------OK-------------------------------------

X. LADDERS

CRACKED WELDS -----------------------------BAD RUNGS----------------------------------------------BAD CONNECTIONS------------------------------------------------OK--------------------------------------DAMAGES:MINOR-----------------MAJOR------------------------------------------------------------------

XI. RAISING AND TELESCOPING SYSTEM:

WIRELINE SYSTEM REFER TO API 4E FOR SPECIFICATIONSa) WIRE LINE : FRAYED --------------KINKED --------------------------------------------------------------

CORRODED----------------------------------------------------------------------OK--------------------------------------

b) CABLE CLAMPS:LOOSE-------------------------------------------OK-------------------------------------- NO. OF CLAMPS PROPERLY INSTALLED -------------------------------------------------------------------------

c) SHEAVES AND MOUNTINGS : DAMAGED ------------------OK-------------------------------------

d) EQUALISER ASSY. : DAMAGED ---------------------------------OK-------------------------------------

e) SOCKETS AND PINS : DAMAGED -------------------------------OK-------------------------------------

HYDRAULIC SYSTEM:

1. HYDRAULIC CYLINDERS:i) RAISING : LEAKING-------------------------------------------------OK------------------------------------- EXPOSEDSURFACE--------------------------------------------------OK------------------------------------- CORRODED-------------------------------------------------------------OK-------------------------------------

ii) SCOPING : LEAKING--------------------------------OK------------------------------------- EXPOSED SURFACE -------------------------------------------------OK------------------------------------- CORRODED-------------------------------------------------------------OK-------------------------------------

2. CONNECTIONS : LEAKING ---------------------------------------OK------------------------------ ------3. HOSES & HOSE END FITTING :

EXPOSED WIRE -----------------------CORRODED----------------OK-------------------------------------DAMAGED--------------------------------------------------------------OK-------------------------------------

4. PIN HOLES : OVAL ---------------------------------------------OK------------------------------ ------

5. SCOPING CYLINDER STABILIZERS:BENT ----------------------------------------------------------------------OK-----------------------------------LUBRICATION----------------------------------------------------------OK------------------------------------

MAST GUIDES :

CLEANED AND LUBRICATED - -----------------------------------OK------------------------------------NEEDS ATTENTION---------------------------------------------------OK------------------------------------

XII. LOCKING DEVICES & SEATS - TELESCOPING MASTS

a) PINS, BARS OR PAWLS : DAMAGED---------------------------OK-----------------------------------b) SEATS : DEFORMED -------------------------------------------------

OK------------------------------------c) MECHANISM : DAMAGED -----------------------------------------

OK------------------------------------d) NEEDS CLEANING & LUBRICATION-----------------------------OK-----------------------------------

XIII. GUYLINES ANCHORAGE:a) GUY LINE : DAMAGED---------------------------------------------------------------------------------------b) NEEDS ADJUSTING -------------------------------------------------------------------------------------------c) NEEDS REPLACING--------------------------------------------------- OK-----------------------------------

d) CABLE CLAMPS : LOOSE-------------------------------------------OK------------------------------------e) PROPERLY INSTALLED--------------------------------------------------------------------------------------f) SOME MISSING---------------------------------------------------------OK------------------------------------

PINS AND SAFETY PINS: MISSING-------------------------------OK-----------------------------------

TURNBUCKLES : LOCKED /DAMAGED / REPLACE---------OK------------------------------------

ANCHOR & DEADEND : REPLACE------------------------------OK-----------------------------------

XIV. BOLTED STRUCTURES:

a) ALL BOLTED CONNECTIONS ARE TO BE INSPECTED , TIGHTENED , AND MISSING PARTS REPLACED OR VISIBLY MARKED AS MISSING OR DAMAGED AND IN NEED OF REPAIR.

b) ALL BOLTED CONNECTIONS FOUND TO BE SATISFACTOY AS CHECKED AND LOOSE BOLTS TIGHTENED

c)ALL BOLTED CONNECTIONS VISUALLY INSPECTED AND SPOTCHECKED FOR TIGHTNESS AND NO FURTHER BOLT TIGHTENING OR REPAIRS NECESSARY.

XV. SUMMARY OF INSPECTION OF DERRICK & MAST

a) WAS MANUFACTURER’S ASSY. DRAWING USED YES/NOb) APPEARANCE : GOOD ---------- FAIR ----------- POOR ----------c) REPAIRS NEED : NONE --------- MINOR-------- MAJOR--------d) NUMBER OF MISSING PARTS---------------------------------------

A) SUBSTRUCTURE & VERTICAL EXTENTION

(a) SHOES, PEDESTALS OR PIVOTS: DAMAGED------------------OK-----HOLES: WORN-----------------------------------------------------------OK-----BOLTS: NEED REPLACING-------------------------------------------OK-----PINS: WORN---------------------------------------------------------------OK-----SAFETY PINS: MISSING------------------------------------------------OK-----SUPPORT BEAMS: DAMAGED-------------------------------------------------CORRODED:---------------------------------------------------------------OK-----

(b) FLOORING

DAMAGES: MINOR---------------------------- MAJOR---------------OK-----

(c) SUBSTRUCTURES FOR DERRICK OR MAST & SUB-SPREADERS & ROTARY BEAMS :DAMAGES: MINOR----------------------------MAJOR----------------OK-----CORROSION: MINOR--------------------------MAJOR----------------OK-----CONNECTIONS: WORN----------------------------------------------------------CRACKED WELDS-----------------------------------------------------------------SAFETY PINS: MISSING-------------------------------------------------OK-----

d) ENGINE FOUNDATION SPREADERS :

DAMAGES: MINOR----------------------------------MAJOR------------OK---CORROSION: MINOR--------------------------------MAJOR-----------OK---CONNECTIONS WORN-----------------------------------------------------------CRACKED WELDS---------------------------------------------------------OK--SAFETY PINS: MISSING-------------------------------------------------OK--

e) STAIRWAYS, LANDINGS & HANDRAILS

DAMAGES: MINOR----------------------------------- MAJOR----------OK--

f) HOLD DOWN AND ANCHORING CONNECTIONS :

BOLTS TIGHT------------------------------------------BOLTS MISSING-----DAMAGED--------------------------------------------------------------------------

NEEDS REPAIRING---------------------------------------------------------OK-

g) FOUNDATION:

ADEQUATE : YES-------------------NO--------------WHY----------------------

h) SUMMARY OF INSPECTION OF SUBSTRUCTURE & VERTICAL EXTENTION

APPEARANCE: GOOD-------------FAIR-------------POOR---------------------REPAIR NEEDED: NONE-------------MINOR----------MAJOR----------------WAS MANUFACTURE’S ASSEMBLY DRAWING USED? YES--------NO-----------NUMBER OF MISSING PARTS----------------------------------------------------------------

LOCALISED CLEANING DONE: _____________________________SAND BLASTING DONE:____________________________________NDT DONE:(MPI/UT) _________________________________

HORIZONTAL MEMBER: SLIGHT DAMAGE _______________; BADLY DAMAGED ____________;CRACKED WELDS ______________; NEED REPAIR _________________;

VERTICAL MEMBER:SLIGHT DAMAGE _______________; BADLY DAMAGED ____________;CRACKED WELDS ______________; NEED REPAIR _________________;

DIAGONAL MEMBER:SLIGHT DAMAGE _______________; BADLY DAMAGED ____________;CRACKED WELDS ______________; NEED REPAIR _________________;

FEET:DAMAGED _____________________; CRACKED WELDS ______________;CORRODED ___________________ ; WORN HOLES _________________ ;WORN PINS ____________________; NEED REPAIR ________________ ;

B) SUBSTRUCTURE FOR DERRICK OR MAST :

PRIMARY LOAD BEARING MEMBER:SLIGHT DAMAGE _______________; BADLY DAMAGED ____________;CRACKED WELDS ______________; NEED REPAIR _________________;NEED REPLACEMENT ______________;

SECONDARY LOAD BEARING MEMBER:SLIGHT DAMAGE _______________; BADLY DAMAGED ____________;CRACKED WELDS ______________; NEED REPAIR _________________;NEED REPLACEMENT ______________;

ANY OTHER MEMBER(INCLUDING DIAGONAL):SLIGHT DAMAGE _______________; BADLY DAMAGED ____________;CRACKED WELDS ______________; NEED REPAIR _________________;NEED REPLACEMENT ______________;

FLOORING:DAMAGES: MINOR__________; MAJOR ________;

REPAIR NEEDED_____________ ; REPLACEMENT NEEDED __________;CORROSION: MINOR_______; MAJOR ________; NONE _____________ ;

PAINTING DONE:YES _________. NO _______________. APPEARANCE __________

ELECTRICAL LIGHTING

ADEQUATE GENERAL LIGHTING ARRANGEMENTS AVAILABLE DURING THE WORKING HOURS AT :

A)DERRICK FLOOR YES NOB)MONKEY BOARD YES NOC)DRILLER’S END YES NOD)DOG HOUSE YES NOE)BOP CONTROL YES NOF)CAT WALK YES NOG)EVERY PLACE WHERE PERSONS ARE TO WORK YES NOH)EVERY PLACE OF ESCAPE/ACCESS YES NO

- LIGHTING PROVIDED AT THE MAST /SUB STRUCTUREIS SO ARRANGED THAT IT DOES NOT CAUSE ANY GLARE

OR EYE STRAIN. YES NO- LIGHTING PROVIDED AT MAST / SUB STRUCTURE IS OF

INCREASED SAFETY TYPE AS PER ZONE 2 REQUIREMENT OF OMR YES NO

- PROPER CARE HAS BEEN TAKEN WHILE FITMENT OFLIGHTING APPARATUS TO AVOID ACCIDENTAL DAMAGE YES NO

- ADEQUATE WIRE GUARDS ARE PLACED OVER THE YES NOTOUGHENED GLASS.

- AVIATION LIGHT OF INTERMITTENT TYPE IS FITTED AT TOP YES NOOF THE MAST.

- EMERGENCY/SAFETY TORCH IS AVAILABLE AND PROPERLY MAINTAINED. YES NO

- LIGHTING VOLTAGE PHASE TO PHASE IS O.K. (215V) YES NO

EARTHING

- EQUIPMENT / MAST ARE DOUBLE EARTHED WITH YES NOAPPROPRIATE GI STRIP.

- MAINTENANCE OF EARTHING PIT AND ITS RESISTANCE YES NOMEASUREMENT DONE AT EACH NEW LOCATION DURING

DURING RIG BUILDING / SIX MONTHLY.

CABLE CONNECTIONS

- CABLES ARE LAID DOWN IN THE CABLE TRENCHES AS YES NOPER CODE OF PRACTICES I.E.BIS-255A

- CABLE CONNECTIONS HAVE BEEN PROVIDED YES NOWITH DOUBLE COMPRESSION GLANDS.

- RECEPTACLES AND PLUGS ARE IN GOOD CONDITION. YES NO- INSULATION IS REGULARLY CHECKED AT THE NEW LOCATION DURING RIG BUILDING AND SUBSEQUENTLY . YES NO- FLP /INCREASED SAFETY FEATURES(AS PER ZONE CLASSIFICATION)OF JUNCTION

BOXES ,LIGHTING AND CABLE CONNECTION VIZ. AIR GAP, GLANDS ETC ARE MAINTAINED IN HAZARDOUS ZONES. YES NO

REMARKS : __________________________________________________________________

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