Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public.

इंटरनेट मानक

“!ान $ एक न' भारत का +नम-ण”Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“प0रा1 को छोड न' 5 तरफ”Jawaharlal Nehru

“Step Out From the Old to the New”

“जान1 का अ+धकार, जी1 का अ+धकार”Mazdoor Kisan Shakti Sangathan

“The Right to Information, The Right to Live”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता है”Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 8780 (2004): Non-Destructive Testing of Steel Castings -Code of Practice [MTD 21: Non-Destructive Testing]

IS 8780:2004

13g-m?ifam

Indian Standard

NON-DESTRUCTIVE TESTING OF STEELCASTINGS — CODE OF PRACTICE

( First Revision)

lCS 77.040.20

0 BIS 2004

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

Seplember 2004 Price Group 3

Non-destructive Testing Sectional Committee, MTD 21

1’OREWORD”

This Indian Standard ( First Revision) was adopted by the Bureau of Indian Standards, after the draft finalized bytbc Non-destructive Testing Sectional Committee had been approved by the Metallurgical Engineering DivisioncoLlllc il.

[“hestanciarci was first publisiled in 1978 whiie reviewing this standard in the light of experience gained duringtilcse years. Tile Committee feit to revise tilis standard, while revising this standard following modifications havebeen made:

a) Scope has been modified.

i~) Reference clause has been incorporated in this revision.

c) CIILISC for safety precaution has been introduced for the personnei who are invoived in the radiographictesting. For this purpose, reference shali be made to the following Atomic Energy Regulatory Board( AERB ) guides:

1) SG/IN - 1 Radiological safety in enclosed radiography installation, and

2) SG/IN-2 Radiological safety in open fieid radiography.

d) Clause for personnei requirements has been incorporated.

For tile purpose of deciding whether a particular requirement of this standard is complied with, the finalvaiue observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance withIS 2:1960 ‘Ruies for rounding off numericai vaiues ( revi.$ed)’. The number of significant places retained in therounded off value should be the same as that of the specified value in this standard.

IS 8780:2004

Indian Standard

NON-DESTRUCTIVE TESTING OF STEELCASTINGS — CODE OF PRACTICE

( First Revision)

1 SCOPE

This standard descr,jbes requirements and methodsfor non-destructive testing of steel castings. Thesenon-destructive testing methods are intended todetect surface and internal discontinuities in castings.They include visual testing, magnetic particle testing,liquid penetrant testing, radiographic testing andultrasonic testing.

2 REFERENCES

The following standards contain provisions whichthrough reference in this text, constitute provisionof this standard. At the time of publication, the editionsindicated were valid. All standards are subject torevision, and parties to agreements based on thisstandard are encouraged to investigate the possibilityof applying the most recent editions of the standardsindicated below:

IS No,

2417:2003

2478:1991

2595:1978

2953:1985

3415:1998

3657: 1978

3658:1999

3703: 1980

7666:1988

Title

Glossary of terms relating toultrasonic testing ( secondrevision )

Glossary of terms relating toindustrial radiography ( second

revision )

Code of practice for radiographictesting (first revision )

Glossary of terms used forinterpretation of welds and castingsradiographs (,first revision )

Glossary of terms used in magneticparticle flaw detection ( second

revision )

Radiographic image qualityindicators (first revision )

Code of practice for liquid penetrantflaw detection ( second revision)

Code of practice for magnetic particleflow detection (first revision )

Ultrasonic examination of ferriticcastings of carbon and low alloysteel — Recommended procedure(first revision )

1

IS No, Title

13805:2004 General standard for qualificationand certification of NDT personnel

3 TERMINOLOGY

For the purpose of this standard, the definitionsgiven in 1S2417, IS 2478, IS 2953 and IS 3415 shallapply, in addition to the following.

3.1 Defect — A flaw ( imperfection or unintentionaldiscontinuity ) of such size, orientation, location orproperties as to be rejectable.

3.2 Discontinuity — A lack of continuity of cohesion,an interruption in the normal physical structure ofmaterial or a product.

3.3 Flaw — An imperfection or unintentionaldiscontinuity which is detectable by a non-destructivetesting.

3.4 Imperfection — A condition of being imperfect,a departure of a quality characteristic from itsintended condition.

3.5 Indication — The response or evidence from theapplication of a non-destructive testing.

4 SAFETY PRECAUTIONS

4.1 Methods used may involve hazardousmaterials, operations and equipment. It is theresponsibility of the user of this standard to establishappropriate health and safety precautions.

4.2 When performing radiography with X-rays orgamma rays adequate precautions are taken toprotect the radiographer and other personnel in thevicinity. For details about radiation protection,reference may be made to Atomic Energy RegulatoryBoard SG/lN- 1 and Atomic Energy Regulatory BoardSGIN2.

5 PERSONNEL REQUIREMENTS

Personnel performing non-destructive testing andevaluation shall be qualified in respective methodsand for appropriate levels in accordance with therequirements of IS 13805 or any other equivalentcertification schemes.

IS 8780:2004

6 APPLICABLE TEST METHODS

All castings shall be subjected to visual examinationat various stages of manufacture to detect any surfacedefect. In addition to this any one or more of thefollowing method(s) as applicable maybe carried outwith the mutual agreement between the purchaser andthe manufacturer.

6.1 Magnetic Particle Testing

This is a surface and subsurface flaw detectionmethod which may be used for ferromagnetic steelcastings.

6.2 Liquid Penetrant Testing

This is a method for detection of flaws open to surfaceand can be applied on all types of castings.

6.3 Radiographic Testing

This method may be applied to steel castings fordetection of surface and internal flaws and has theadvantage of being able to provide a permanent recordon films.

6.4 Ultrasonic Testing

This method is generally applied for steel castingsof suitable shape and sizes for the detection of internalflaws and has the advantage that it may be appliedto large thickness of material.

7 VISUAL EXAMINATION

7.1 Introduction

This section deals with the visual examination of alltypes of steel castings. Surface testing shall be carriedout at specific stages during the processing of thecastings.

7.2 Equipment and Procedure

7.2.1 Direct Visual Testing

Direct visual examination may usually be made whenaccess is sufficient to place the eye within 60 cm ofthe surface to be examined and at an angle not lessthan 30° to the surface to be examined. Mirror maybe used to improve the angle of vision and aids suchas a magnifying lens may be used to assist testing.The illumination on the surface is required to be notless than 500 lUX.

7.2.2 Remote Visual Examination

Remote visual examination may use visual aids suchas mirrors, telescopes, borescope, fiberscope,videoscope or other suitable instruments and shallhave a resolution capability at least equivalent to thatof direct observation.

7.3 Stage of Examination

7.3.1 Examination of Cast Components

Initial testing shall be carried out after the casting hasbeen fettled and cleaned.

7.3.2 Examination after Defect Removal and Weld

Repair

Visual examination shall be carried out after defectremoval to make sure that previously revealed defectis removed completely. The final examination shallbe carried out after completion of welding andpreferably afier heat treatment, if any.

7.4 Evaluation

All results shall be evaluated in terms of relevantacceptance standard.

7.5 Documentation

The date of examination, the examination procedureused and results shall be documented and certified.The illuminators, instruments, tools, equipments, etc,used shall be identified in the report.

8 MAGNETIC PARTICLE TESTING

8.1 Introduction

This section deals with the magnetic particle testingmethod of surface/sub surface flaw detection in theferromagnetic steel castings. Finely divided magneticparticles are applied to the surface of the castingswhich has been suitably magnetized. The particlesare attached to regions of magnetic flux leakageassociated with defects and discontinuities, thusproducing indications which are observed visually.The magnetic particles are applied either as dry powderor in a wet suspension in liquid medium. The testingshall be carried out as per IS 3703.

8.2 Surface Preparation

8.2.1 In general, satisfactory results maybe obtainedwhen the surface is in as cast condition, free flom sandand dirt. However, in some cases, surface preparationby grinding or machining may be necessary whensurface irregularities would otherwise mask theindication from discontinuities. All sharp edges andcorners shall be ground to smooth curved surface.

8.2.2 If magnetic particles do not give good contraston the casting surface, a thin coating of white paintmay be applied to the surface under test.

8.3 Testing Procedure

8.3.1 The entire casting to be tested shall bemagnetized and separately examined in two mutuallyperpendicular directions.

2

8.4 Non Relevant Indications

Non relevant indications are caused by distortion ofmagnetic field resulting from magnetic writing, coldworking, hard and soft spots, boundaries of heateffected zone, abrupt change in section, etc. Care shallbe taken to identify and eliminate them as they maymask the actual defect.

NOTE — Casting which exhibit significant residualmagnetismshould be demagnetizedon completionoftest when specified by the purchaser.

8.5 Evaluation

All the indications shall be evaluated with respect tothe acceptance/rejection criteria for their relevencyas a flaw, indications related to flaws shall be evaluatedfor the type and extent of flaw.

8.6 Documentation

Report for test carried out shall include areaexamined, magnetization technique, type of magneticparticles used and its application, value of magnetizingcurrent, surface preparation, demagnetization detailsand results.

9 LIQUID PENETRANT TESTING

9.1 Introduction

This section deals with the liquid penetrant testingmethod of surface flaw detection of all types of steelcastings. The liquid is applied to the clean and drysurface of casting to detect discontinuities, which areopen to the surface. Sufilcient time is allowed for thepenetrant to remain on the surface during which itpenetrates in all the discontinuities. Excess pentranton the surface is removed without removing thepenetrant, which gets entrapped into thediscontinuities. A thin coat of developer, which actsas a blotter is then applied to the surface. The blottingaction of developer draws the penetrant from thediscontinuity and the penetrant appears as anindication on the surface ( see also IS 3658 ).

9.2 Surface Preparation

In general, satisfactory results maybe obtained whenthe surface is in as cast condition, in case of investmentcasting, centrifugal casting and die casting. In somecases, however, surface preparation by grindingor machining may be necessary when surfaceirregularities would otherwise mask the indicationsof discontinuities.

NOTE— Blastingwith shot or dull sand, rotofinishing,buffing, wire brushing or machining with dull tools maybe used with caution as they may block the discontinuitiesat the surface.

9.2.1 The surface to be tested and any adjacent area

3

IS 8780:2004

should be dry and free from any dirt, grease, lint, scale,oil or any extraneous matter that would obscure surfaceopening or otherwise interfere with the testing.

9.2.2’ Typical cleaning agents which may be used aredetergents, organic solvents, descaling solutions andpaint removers.

9.3 Examination

Itis a good practice to observe the surface duringthe application of the developer in order to detectthe nature of certain indications which might tendto bleed out profusely. Final interpretation,however, shall be made after allowing the penetrantto bleed out for a period not less than the specifieddeveloping time.

9.4 Evaluation

Indications, if any, shall be evaluated for acceptance/rejection, based on the applicable standards.

9.5 Post Cleaning

Casting shall be properly cleaned using a cleaningagent to remove any trace of developer/penetrant.

9.6 Documentation

Report of test carried out shall include typepenetrant, method, area examined and results.

10 RADIOGRAPHIC TESTING

10.1 Introduction

This section deals with radiographic testing

of

ofcastings for discontinuities with the use of radiographicfilm as the recording medium and X-ray and/or gammarays as source of radiation. Other fimless recordingmay also be used, with mutual agreement, providedthe sensitivity levels are met. Radiographic testingshall be carried out as per IS 2595.

10.2 Surface Preparation

Castings should be fettled and loose scale andexcessive roughness should be removed. Where localgrinding is necessary, care should be taken to preservethe natural profile of the castings. A good as-castsurface is adequate.

10.3 Identification

Each section of the casting radiographed shouldhave suitable symbols affixed to identify the castingand the area of the casting under testing. The leadletters or numerals should in general be placed on thesurface facing the source of radiation. Where this isnot possible, they may be placed on the film side ofthe casting.

1S8780:2004

10.4 Image Quality Indicators

In order to ascertain the quality of radiographs, imagequality indicators ( IQIs ) shall be used as describedbelow:

a) Any one or two types of IQIs described inIS 365’7may be used.

b) If the zone covered in radiography includesmore than one section thicknesses, one IQIfor every thickness shall be placed.

c) If the casting surface is smooth, the wire typeIQI or step-hole type can be directly placedon the casting. If step-hole type IQI isemployed, it shall be placed on a block ofidentical material, having same thickness asthe area being radiographed. This block shallbe kept directly on the film, just by the sideof casting. This method shall be adopted, ifthe surface roughness of the casting is likelyto interfere with the IQI image.

d) Unless specified otherwise, 2 percentsensitivity will be achieved, which has thefollowing meaning:

1) For step-hole type IQI, image of the stepand the hole in the same step shall beseen. The step thickness shall be 2percent of the section thickness beingradiographed. If the Table 2 in IS 3657does not have a step of requiredthickness, next higher step can beaccepted.

2) For wire type IQI, the wire diameter shallbe 2 percent of the job thickness. If theTable 1 in IS 3657 does not have a wireof required diameter, next higher diametercan be accepted.

3) For strip-hole IQI, the thickness of thestrip shall be 2 percent of the jobthickness. The hole shall be visible. IfIQI of required thickness is not available,next higher step can be accepted.

10,5 Evaluation

Reference radiographs illustrating grades of variouscasting discontinuities shall be used to help establishacceptance criteria during interpretation ofradiographs.

10.6 Documents

The following radiographic records shall be maintainedas a minimum.

10.6.1 Radiographic Standard Shooting Sketch

10.6.2 Documentation on Repair by Welding f

Carried Out

10.6.3 Radiographs and/or Digitized Image in Case

of Film less Radiography

10.6.4 Interpretation Record

11 ULTRASONIC FLAW DETECTION

11.1 Introduction

This section deals with the ultrasonic testing andwall thickness measurements of steel castings.Usually, normal beam technique is used for flawdetection in casting.

11.1.1 Casting Condition

Ultrasonic testing shall be carried out on the castingafier grain refining heat treabnent and prior to machiningof those areas which could interfere with testing.

11.1.2 Test Condition

To assure complete coverage each pass of the searchunit shall overlap by at least 10 percent of the width/diameter of the transducer.

11.2 Testing Procedure

Ultrasonic testing of ferritic steel castings shouldbe carried out in accordance with IS 7666.

11.2.1 Selection of Testing Technique

Selection of the testing technique depends upon thefollowing factors:

a) Type, orientation, position and incidence ofdefects likely to be encountered in the castingunder consideration;

b) Thickness and profile of the section; and

c) Metallurgical condition.

11.2.2 Test Frequency

For all ultrasonic examinations, the highestfrequency compatible with the size, metallurgicalcondition and thickens of the casting should beused. Normally test frequencies in the range of0.5 MHz to 2 MHz are adequate. However, theoptimum frequency compatible with the size,metallurgical condition and thickness of the castingshall be used.

11.2.3 Procedure

All parts of the casting surface where a contactprobe may be used, should be tested, irrespective ofcasting geometry of whether a back wall signal isobtained for use as a reference. A longitudinal waveprobe of a frequency of 2 MHz should normally beused but should be augmented a necessary by anglebeam. When examining areas which have to bemachined, a double crystal probe should be used to

4

IS 8780:2004

minimize dead zone problems. This type of probe

should be used for the examination of thin sections.Where large areas have to be covered, a probe givinga beam of larger diameter should be used for an initialsearch for defects. A more critical examination ofsuspected area, if any, shall be made. It should benoted that crystals of each twin-crystal probe havetheir angle of incidence and so its own range oftesting depth and dead-zone. An angle beam probeis useful when assessing defect size and type,for examination under difficult geometricconditions and for the detection of unfavorableoriented defects.

11.3 Wall Thickness Measurement

Using the pulse echo-technique longitudinal waveprobes may be used for thickness measurement of

casting by directly calibrating the time base scale againstparallel surfaces of the same casting having a knownthickness. For this application, the highest frequency

compatible with the material under examination shouldbe used. Using this procedure, the accuracy of themeasurement shall be about 2 percent to 5 percent ofthe section thickness, but shall depend upon two mainfactors, that is the surface roughness and whetheror not the surface are parallel.

11.4 Evaluation

The results of the test shall be evaluated withrespect to the acceptance criteria, for their relevanceas a flaw.

11.5 Documents

The manufacturer’s report shall contain the examinationfrequency, type of instrument, reference block, typeof search unit, couplant, location, size and echoamplitude of defects and a sketch showing the locationof all indications and areas not inspected due togeometric configuration.

Bureau of Indian Standards

BIS is a statutory institution established under the Bureau qf India}? ,Y[andurdy Act, 1986 to promoteharmonious development of the activities of standardization, marking and quality certification of goods and

attending to connected matters in the country,

Copyright

131Shas the copyright of all its publications. No part of these publications may be reproduced in any for-mwithootthe prior permission in writing of BIS. This does not preclude the free use, inthe course ofirnplementingthe standard, of necessary details, such as symbols and sizes, type or grade designations, Enquiries relating

to copyright be addressed to [be Director (Publications), BIS.

Review of Indian Standards

Amendments are issued to standards asthe need arises on the basis of comments. Stanciards are also reviewedperiodically; a standard along with amendments is reaffirmed when sLlchreview indicates that no changes areneeded; if the review indicates that changes are needed, it is taken up for revision. Users of Indian Standardsshouid ascer~ain that they are in possession of the !atest amendments or edition by referring to the latest issue

of ‘131S Catalogue’ and ‘Standards : Monthly Additions’.

This Indian Standard has been developed from Doc : No. MTD21 (4242).

Amendments Issued Since Publication

Amend No. Date of Issue Text Affected

BUREAU OF INDIAN STANDARDS

Headquarters:

Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi 110002Telephones: 23230131,23233375,2323 9402 Website: www.bis. org. in

Regional Offices : Telephones

Central :

Eastern :

Northern :

Southern:

Western :

Manak Bhavan, 9 Bahadur Shah Zafar Mar-g

{

23237617NEW DELHI 11OOO2 23233841

l/14C. I.T. Scheme VI IM, V. I. P. Road, Kankurgachi

{

23378499,23378561KOLKATA 700054 23378626,23379120

SCO 335-336, Sector 34-A, CHANDIGARH 160022

{

2603843~6092~5

C. I. T. Campus, lV Cross Road, CHENNAI 600113

{

2254 1216,2254 1442

?254 2519,22542315

Manakalaya, E9 MlDC, Marol, Andheri (East) ~ 28329295,28327858MUMBA1400093 ~ 28327891,28327892

Branches : AHMEDABAD. BANGALORE. BHOPAL. BHUBANESHWAR. COIMBATORE.FARIDABAD. GHAZIABAD. GUWAHAT1. HYDERABAD. JAIPUR. KANPUR.LUCKNOW. NAGPUR. NALAGARH. PATNA. PUNE. R.AJKOT. THIRUVANANH-IAPURAM.VISAKHAPATNAM. —-

Prlnkd HI Ne\v India I’nntlng Press, Kl]urja, India