S1450401 - Corus - Execution and inspection of steel welding.pdf

8/10/2019 S1450401 - Corus - Execution and inspection of steel welding.pdf

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S1 45 04 01 Corus Standard

Execution and inspection of steel welding

Author: P.W.L. Lensen / V.H.M. Reus

Issue: March 2002

Version 4.0

Intended for location IJmuiden

This is a non-registered document.

In case of future changes, amendments will not be sent to you.

The latest version can be retrieved from Intranet of Corus (project.net).

Information on:

Contents of document P.W.L. Lensen Tel. +31 (0)251-4 95242

V.H.M. Reus Tel. +31 (0)251-4 92911

Standardisation Standardisation office Tel. +31 (0)251-4 97693


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Contents:

1. GENERAL STIPULATIONS.................................................................................................................................3

1.1. GENERAL...............................................................................................................................................................3 1.1.1. Scope................................................................................................................................................................3 1.1.2. Rules ................................................................... ................................................................ ............................. 31.1.3. Conflicting requirements .................................................................................................................................31.1.4. Order of priority ..............................................................................................................................................3

1.2. WELDING INSPECTORATE ......................................................................................................................................4 1.3. CLASSIFICATION....................................................................................................................................................4

1.3.1. Categories........................................................................................................................................................4 1.3.2. Pressure vessels ........................................................... ................................................................. ................... 41.3.3. Special Corus regulations................................................................................................................................41.3.4. Classification by the supplier...........................................................................................................................4

1.4. MATERIAL .............................................................................................................................................................5 1.5. TESTING ................................................................................................................................................................5

1.5.1. Inspection plan............................... ........................................................... ....................................................... 51.5.2. Quality assurance and documents ....................................................... ............................................................ 6

1.5.3. Inspections .......................................................... ................................................................ ............................. 61.5.4. Non-destructive testing reports................................... .................................................................. ................... 61.5.5. Repairs........................................................... ............................................................. ..................................... 61.5.6. R.T.D...................... ........................................................... ............................................................ ................... 71.5.7. Cost settlement.................................................................................................................................................7

1.6. REPAIRS.................................................................................................................................................................7 1.7. REMOVAL ..............................................................................................................................................................7 1.8. WORKING CONDITIONS ..........................................................................................................................................7 1.9. STRESS RELIEVING ANNEALING .............................................................................................................................8 1.10. CLAD WELDING .....................................................................................................................................................8

1.10.1. Clad welding by means of cladding material equal to the workpiece material properties.........................8 1.10.2. Clad welding by means of cladding material unequal to the workpiece material properties.................... 81.10.3. Welding procedures ....................................................................................................................................8

1.10.4 Welding method and welders qualifications..............................................................................................91.10.5. Inspection.......................................................... ............................................................. ............................. 9

2. WELDING CATEGORY 1 .......................................................... ................................................................ ........10

2.1. EXECUTION .........................................................................................................................................................10 2.1.1. Supplier..........................................................................................................................................................10 2.1.2. Welders ...................................................... ................................................................ .................................... 102.1.3. Welding specifications ........................................................ ................................................................... ........102.1.4. Welding consumables ....................................................................................................................................10

2.2. TESTING ..............................................................................................................................................................11 2.2.1. Scope and nature of the test...........................................................................................................................112.2.2. Execution of the test ................................................................ ............................................................... ........11

3. WELDING CATEGORY 2 .......................................................... ................................................................ ........123.1. EXECUTION .........................................................................................................................................................12

3.1.1. Supplier..........................................................................................................................................................12 3.1.2. Welders ...................................................... ................................................................ .................................... 123.1.3. Welding specifications ........................................................ ................................................................... ........123.1.4. Welding consumables ....................................................................................................................................12

3.2. TESTING ..............................................................................................................................................................13 3.2.1. Scope of the test .............................................................................................................................................133.2.2. Execution of the test ................................................................ ............................................................... ........13

4. WELDING CATEGORY 3 .......................................................... ................................................................ ........14

Corus Standard Page 1 of 23

Corus Services IJmuiden

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4.1. EXECUTION ..........................................................................................................................................................14 4.2. TEST ....................................................................................................................................................................14 4.3. CONDITIONS ........................................................................................................................................................14

5. REQUIREMENTS FOR STAINLESS AND HIGHLY HEAT-RESISTANT STEEL...................................15

5.1. GENERAL .............................................................................................................................................................15 5.1.1. Material storage.......................... ................................................................ ...................................................155.1.2. Workshop accommodation.............................................................................................................................155.1.3. Tools...............................................................................................................................................................15 5.1.4. Weld preparation ...........................................................................................................................................155.1.5. Welding execution ............................................................... .......................................................... .................165.1.6. Welding consumables.....................................................................................................................................16

5.2. HEAT TREATMENT ...............................................................................................................................................16 5.3. WELD FINISHING..................................................................................................................................................16

6. LIST OF CLASSIFICATION OF WELDING IN WELDING CATEGORIES .............................................17

6.1. STEEL STRUCTURES .............................................................................................................................................17 6.1.1. Welding category 1 ........................................................................................................................................176.1.2. Welding category 2 ........................................................................................................................................176.1.3. Welding category 3 ........................................................................................................................................17

6.2. BOILERS / PRESSURE VESSELS / MACHINERY........................................................................................................17

6.2.1. Welding category 1 ........................................................................................................................................176.2.2. Welding category 2 ........................................................................................................................................186.2.3. Welding category 3 ........................................................................................................................................18

6.3. MACHINES / INSTRUMENTS ..................................................................................................................................18 6.3.1. Welding category 1 ........................................................................................................................................186.3.2. Welding category 2 ........................................................................................................................................186.3.3. Welding category 3 ........................................................................................................................................18

6.4. HOISTING AND TRANSPORT EQUIPMENT ...............................................................................................................18 6.4.1. Welding category 1 ........................................................................................................................................186.4.2. Welding category 2 ........................................................................................................................................186.4.3. Welding category 3 ........................................................................................................................................18

6.5. PIPELINES ............................................................................................................................................................19 6.5.1. Welding category 1 ........................................................................................................................................19

6.5.2. Welding category 2 ........................................................................................................................................196.5.3. Welding category 3 ........................................................................................................................................19

7. REFERENCES ............................................................. ............................................................... ..........................20

8. STATEMENT .............................................................. ................................................................ ..........................22

9. APPENDICES: NON-DESTRUCTIVE TESTING PROCEDURES .............................................................23

9.1. UT-97001 PROCEDURE FOR ULTRASONIC EXAMINATION. ......................................................... ..........................239.2. UT-97002 PROCEDURE FOR ULTRASONIC EXAMINATION FOR INTERNAL IMPERFECTIONS IN STEEL. ...................239.3. MT-97003 PROCEDURE FOR MAGNETIC EXAMINATION. .................................................. ....................................239.4. PT-97004 PROCEDURE FOR PENETRANT EXAMINATION.......................................................................................23 9.5.

RT-97005 PROCEDURE FOR RADIOGRAPHIC EXAMINATION.................................................................................23



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1. GENERAL STIPULATIONS

1.1. General

1.1.1. Scope

This Corus Standard stipulates rules for welding and clad welding of machine parts, steel

structures, vessels, equipment and piping of unalloyed, low alloyed and high alloyed steel.

1.1.2. Rules

The welding must always meet legal requirements and the (possible supplementary)

requirements of a third party authority. Moreover, the customer can also set supplementary

requirements in accordance with a third party authority.

The stipulations in this Corus Standard apply to the execution of steel welding, unlessother stipulations are set in the order and related drawings and/or specifications. Any

deviation from this Corus Standard, or the stipulations of the order is not allowed, unless a

written permission has been granted by the customer.

The stipulations of the Corus Standard only apply when their scope is more far-reaching

and not in conflict with legal stipulations and the stipulations of any third party authority.

1.1.3. Conflicting requirements

Conflicting requirements must be brought to the attention of the contractor in writing by

way of explanation. In the event that this is omitted, the most stringent requirements will

apply.

1.1.4. Order of priority

Order of priority of documents stated in the requisition:

Legal requirements

Drawings

Specified requirements

Other specifications



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1.2. Welding inspectorate

Welding inpectorate is defined as follows.

The customers inspector, as well as any other accredited inspection authority appointed

by the customer or an authority pursuant to any legal stipulation.

At any stage the welding inspectorate may determine that the work must be discontinuedbefore granting its permission. This permission can be made subject to one or more

conditions being met. Article 5 of the Terms & Conditions of Delivery of Corus applies

here.

1.3. Classification

1.3.1. Categories

The customer classifies welding as category 1, 2 or 3 in accordance with Chapter 6. This

classification must be stated on (working) drawings, special regulations, and specialstandards or on the order. Besides the general stipulations of these regulations, the

stipulations to be met by the category in question will also apply.

The welding category should preferably be indicated by means of the classification

designation in the suffix of the weld designation in accordance with ISO 2553.

1.3.2. Pressure vessels

Please refer to the rules concerned in the case of systems to which the Rules for Pressure

Vessels (Stoomwezen) [Steam Vessel Inspectorate] apply. In the event that the regulations

of the Gasunie apply, these are determinative.

1.3.3. Special Corus regulations

Please refer to these regulations in the case of systems for which special Corus regulations

have been compiled -- such as ATVK (Mechanical specifications for electric cranes and

bulk handling machines), standard drawings, etc..

1.3.4. Classification by the supplier

If the welding has not been classified as category 1, 2 or 3 on the order, the supplier is

obliged to classify the welding and to submit the proposal to the customer for written

approval. This should be carried out in accordance with Chapter 6 of this Corus Standard.



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1.4. Material

Welded structures must be made of sound and suitable materials. The welding

specifications (see Paragraphs 2.1.3. and 3.1.3.) and consumables (see Paragraphs 2.1.4.

and 3.1.4.) must be in accordance with the welding properties of the selected material.

Please refer to NPR-EGKS 2 for welding fine-grained structural steels.If otherwise specified, material for welding classified as welding category 1 or 2 must be

delivered with inspection certificate 3.1.B in accordance with EN 20104 mentioning the

mechanical values.

The supplier must ensure the material identification (restamp) is carried out by means of

a procedure approved by the customer.

It is not permitted to make welded joints on surfaces with weld primers. If weld primers

have been used, these must be removed in advance.

Welding classified as welding category 1 and 2 must be subjected to a surface zoneinspection for laminations and/or segregation in accordance with procedure 97002 (see

appendix) prior to welding if this involves welded joints that exert stress towards the

direction of the thickness.

1.5. Testing

1.5.1. Inspection plan

The supplier must have the welding tested by means of non-destructive testing methods

and in accordance with the inspection plan approved by the Corus inspection department.This inspection plan must include all data required for the welding category in question.

Each test must be performed after a visual check. The visual check must be repeated in the

case of weld seam machining.

The nature and scope of the test is described in greater detail at the welding categories and

in the inspection plan. The procedures involved in non-destructive testing performed by

the RTD are laid down in the appendices of Chapter 9. (Appendices)

In the event that parties other than the RTD perform the non-destructive tests, the same

procedures must be used.



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1.5.6. R.T.D.

Corus recognises the RTD (Rntgen Technische Dienst) [Radiographic Technical

Department] as the executive authority for non-destructive testing. In case of using another

inspection authority, a written permission of our inspection department for each individual

case is required.The welding inspectorate remains entitled at all times to have supplementary non-

destructive tests performed by an authority appointed by Corus.

1.5.7. Cost settlement

Unless stipulated otherwise in the contract, all costs involved in non-destructive tests are

for the account of the contractor, except in those cases where the Corus Inspection

Department itself has ordered the performance of non-destructive testing.

Retesting after repairs are always for the account of the contractor. In the event that the

non-destructive test must be extended due to poor results, these costs are also for theaccount of the contractor.

1.6. Repairs

If stress relieving has taken place or if the weld has been exposed to a corrosive medium, it

may only be repaired once. In all other cases when the results of the test are unacceptable,

the weld may be repaired twice. Each repair made on these grounds must again be

submitted to a 100% non-destructive test and the end results must meet the original

requirements. If that is not the case, the welds in question must be removed completely.

The customer must be consulted in all cases.

1.7. Removal

Attachments and fixed parts may only be removed by means of grinding. Any other form

of removal will result in immediate rejection.

1.8. Working conditions

Special measures must be taken in the following cases.

If the ambient temperature is lower than 5 C. If the welding site is exposed to a windforce in excess of 5 Beaufort.



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1.9. Stress relieving annealing

The conditions below must be met when stress relieving annealing is prescribed:

The annealing procedure must be included in the inspection plan in question.

The equipment and measuring instruments used must be calibrated. The prescribed non-destructive test must be performed after annealing.

The performance of the heat treatment must be recorded by a writing recorder.

For unalloyed construction steel with a yield up to and including 355N/m2, the stress

relieving annealing temperature may not exceed 580C and the heat treatment may not

last more than one hour. This is in accordance with EN 10025: prolonged annealing may

result in decline of mechanical qualities. In case prolonged annealing in higher

temperatures is desirable, this should be agreed upon in the order. The annealing

temperature of refined steel should be at least 50C lower than the discharge temperature

applied by the steel manufacturer. In case of high yielded and low alloyed steel it is notallowed to go beyond the annealing temperature prescribed by the steel supplier.

1.10. Clad welding

Below mentioned regulations are in addition to the rules of this Standard.

1.10.1. Clad welding by means of cladding material equal to the workpiece material properties.

Unless prescribed otherwise, clad welding should be carried out in at least two layers.

Non-destructive examination of clad welded layers can, after any treatment, be restricted to

some visual tests, followed by penetrant or magnetic tests. To determine the relevant testmethod and scope, the Welding Inspectorate should be consulted.

The required weld method and welders qualifications should be drawn up according to

EN 287, EN 288 of EN 1418. Testing can be performed by a blunt weld in a pipe or plate

sample of minimal 12 mm thickness.

1.10.2. Clad welding by means of cladding material unequal to the workpiece material

properties.

This means clad welding of special alloyed parts in order to increase wear resistance

and/or corrosion resistance (except for wear plates).

1.10.3. Welding procedures

Welding procedures should contain at least the following items:

Extent and way of preparation

Surface examination after preparation

Clad welding material



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Required thickness of the cladding layer

Welding order, welding direction and number of cladding layers

Preheating temperature and interlayer temperature (geared to the workpiece material

and

cladding material)

Hardness and surface examination after clad welding and possible treatment

The welding procedures should be offered in advance to the Corus Welding Inspectoratefor approval. Deviation from the prescribed cladding material by Corus IJmuiden is only

permitted after written approval by the customer.

1.10.4 Welding method and welders qualifications

At each application an adjusted welding method and welders qualification are required.

These qualifications should be drawn up in accordance to and after consultation with the

Welding Inspectorate.

In the event of special requirements for hardness and/or chemical composition of the

cladding layer, these aspects should be mentioned in the qualifications.

1.10.5. Inspection

Before starting the work, the scope of inspection as well as the applying non-destructive

testing method should be established in the inspection plan, in consultation with the

Welding

Inspectorate.

In general cracks and visible porous spots will not be accepted. However,in case of some

kinds of hard-cladding alloys, cracks are unavoidable.

For these applications, it is necessary in consultation with the customer to establish in

advance what measure and direction of the cracks are acceptable.

In acquiring the right cladding layer thickness, it might be necessary to do some

pretreatment. After the pretreatment and before starting the clad welding activity, the

relevant measurements should be registered. These measurements should be stated in a

report.



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2. WELDING CATEGORY 1

2.1. Execution

The execution of the welding may not commence until the welding inspectorate hasgranted its permission (approval inspection plan).

Statutory regulations and/or regulations of third party authorities (see Paragraph 5.1.5), in

particular regarding the execution, may deviate from those stated below.

2.1.1. Supplier

The supplier must meet the following conditions:

In possession of a valid certificate in accordance with EN 729, classification 2.

In possession of all documents required for the acceptance of all welding methods to be

used in accordance with EN 288.

Conditions set by the welding inspectorate in each particular case.

2.1.2. Welders

The welders must have a valid qualification in accordance with EN 287-1 for manual

welding or EN 1418 for mechanical or automatic welding.

2.1.3. Welding specifications

The supplier must submit a welding plan in advance to the welding inspectorate for

approval.

The welding specifications stated in this welding plan must meet the stipulations of

EN 287-1 and EN 288, parts 1 to 9.

2.1.4. Welding consumables

The welding consumables and basic material must be meticulously matched. Only those

consumables approved by Controlasand listed in the latest issue of the List of certified

welding consumables may be used. Deviation from this stipulation is only permitted with

the written approval of the welding inspectorate.

Electrodes and other consumables must be stored in a secure and dry environment.



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2.2. Testing

2.2.1. Scope and nature of the test

The full length of each weld must be submitted to a non-destructive test. Deviation fromthis stipulation is only permitted if standards permit or with the approval of the Corus

Inspection Department.

The nature of the non-destructive test (radiographic, ultrasonic, magnetic, etc.) is laid

down in the welding plan.

All welds must be subjected to a 100% visual inspection. Non-butt welds (with slot) are

subjected to a 100% magnetic or liquid penetration inspection.

Butt welds are subjected to a 100% radiographic or ultrasonic inspection.

Supplementary magnetic or liquid penetration inspection can be prescribed.

2.2.2. Execution of the test

The visual inspection must be executed in accordance with EN 970.

The requirements laid down in EN 25817 classification B must be met.

The remaining non-destructive tests must be performed in accordance with the procedures

laid down in the appendices of Chapter 9.



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3.1. Execution

The execution of the welding may not commence until the welding inspectorate hasgranted its permission (approval inspection plan).

Statutory regulations and/or regulations of third party authorities (see Paragraph 5.1.5), in

particular regarding the execution, may deviate from those stated below.

3.1.1. Supplier

The supplier must meet the following conditions:

In possession of a valid certificate in accordance with EN 729 classification 3.

In possession of all documents required for the acceptance of all welding methods to be

used in accordance with EN 288.


3.1.2. Welders

The welders must have a valid qualification in accordance with EN 287-1 for manual

welding or EN 1418 for mechanical or automatic welding.

3.1.3. Welding specifications

The supplier must submit a welding plan in advance to the welding inspectorate for

approval.

The welding specifications stated in this welding plan must meet the stipulations of

EN 287-1 and EN 288, parts 1 to 9.






Electrodes and other consumables must be stored in a secure and dry environment.



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3.2. Testing

3.2.1. Scope of the test

All welds are subjected to a 100% visual inspection.If other standards are not applicable the scope of the remaining non-destructive tests must

meet the all the points below.

At least one inspection of each type of weld by each welder.

All cruciform welds are to be inspected.

Inspection of points indicated by the welding inspectorate.

In total these tests must include at least 10% of the weld length classified as category 2.

If the welding must take place in both a workshop and at an assembly site, the scope of the

inspection must include 10% of the workshop welding and 10% of the on-site welding.

However, on the basis of experience gained during this inspection, the weldinginspectorate can increase the scope.

The nature of the non-destructive test (radiographic, ultrasonic, magnetic, etc.) is written

down in the welding plan.

Non-butt welds (with slot) are inspected magnetically or by liquid penetration.

Butt welds are inspected by radiography or ultrasound.

Supplementary magnetic or liquid penetration inspection can be prescribed.

3.2.2. Execution of the test

The visual inspection must be executed in accordance with EN 970.

The requirements laid down in EN 25817 classification B must be met.

The remaining non-destructive tests must be performed in accordance with the procedures

laid down in the appendices in Chapter 9.



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4.1. Execution

The material must be welded with the appropriate high-quality welding electrode orconsumable. The seams must be properly prepared and cleaned.

The welding must be carried out by experienced welders.

4.2. Test

A visual inspection must be performed in accordance with EN 970.

The welds are visually assessed in accordance with EN 25817, classification C.

4.3. Conditions

The supplier must meet one of the following conditions:

In possession of a valid certificate in accordance with EN 729, classification 4.




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5. REQUIREMENTS FOR STAINLESS AND HIGHLY HEAT-

RESISTANT STEEL

5.1. General

5.1.1. Material storage

Stainless and high-alloyed heat-resistant steel must be stored separately from other

materials. The supports against which stainless steel semi-finished products are placed may

not be made of carbon steel. Materials such as resin-free or coated wood, hardboard, etc.,

are recommended.

It is essential that materials are given identification markings before being stored. These

marks must all be placed on one side so that they can be checked on the non-processing

side.

5.1.2. Workshop accommodation

Welding must be carried out in a suitable area. The processing of stainless and highly heat-

resistant steel must take place in a separate area. If these conditions cannot be met,

effective measures must be taken to meet the approval of the Corus welding inspectorate.

5.1.3. Tools

Stainless and high-alloyed heat-resistant steel may not come into direct contact with

carbon steel tools, tacking equipment, hoisting equipment, etc.

Only grinding tools such as grinding discs, etc., may be used on stainless and highly heat-

resistant steel.

5.1.4. Weld preparation

Appropriate methods such as those below must be used in the preparation:

Machining

Plasma cutting

Laser cutting

Gouging may only be used in exceptional cases. After gouging the welding edges must

always be smoothly ground. The welding edges and the material adjacent to the weld to a

width of 50 mm, must be thoroughly cleaned.



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5.1.5. Welding execution

The execution of the welding must be part of the welding specifications in advance and

must be approved by the Corus welding inspectorate.

Stainless steel may never be welded using the autogenous method.

It is not permitted to strike the welding arc outside the weld seam.

The application of heat to the basic material must be restricted as much as possible.

The TIG process must be used to weld piping and stainless steel DN < 50.

The root in piping > DN 50 must be welded using the TIG process.

Oxidation of metal surfaces during the welding process must be prevented as much as

possible by means of a shielding gas.

See VM 42 for shielding gases.

The last bead (in the case of several layers) must be made on the corrosion side, if

possible.






Electrodes and other consumables must be stored in a dry environment.

5.2. Heat treatment

For heat treatment, please refer to VM 42, Chapter 10 and Appendix A of EN 10088-3.

5.3. Weld finishing

For weld finishing, please refer to VM 42, Chapter 11.The seam and area affected by heat must be finished to guarantee the required corrosion

resistance.



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6. LIST OF CLASSIFICATION OF WELDING IN WELDING

CATEGORIES

Please note:

In case welded joints are made between parts that are not classified in the same weldingcategory, the highest category applies.

6.1. Steel structures

6.1.1. Welding category 1

Crane runways, brake girders, crane runway column heads, brake gantries, rigid gantry

angles, machine foundations, hoisting lugs.

Structures that are subject to fatigue.


Columns, pedestals, trusses, floor beams, secondary beams, structures to support or

suspend boilers, pressure vessels and piping.


Channels and outlet pipes, steel window frames, stairs, platforms, railings, cable racks and

instrument cabinets.

6.2. Boilers / pressure vessels / machinery

If subject to inspection (Stoomwezen-inspection) also subject to Corus Standard

S1 30 04 01.


Joints in pressurised*) components: shells, fronts, walls, pipe fittings with stiffeners, wall

stiffeners, flanges, pipe joints.

Fan blades, annealing hoods, hot-blast stoves, hoisting lugs.

*) Pressurised includes both overpressure and partial vacuum.



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Joints in non-pressurised components that form part of pressure systems. Climbing &

walking irons, insulation brackets, supports, fire tubes in boilers, various pressure vessels.


Welding that is not subject to pressure, outer cladding, screening.

6.3. Machines / instruments


Bearing houses and frames of motors and turbines, wheel constructions, flanges on axles,

machine tool bed structures, hoisting lugs, water-cooled rails in furnaces.


Gear boxes and foundations: stiffeners, consoles, inspection manholes and hatches.

Foundations of various machines.


Handwheels and control levers, light seat frames, protective panels.

6.4. Hoisting and transport equipment


Beams in loading ramps, jibs and cranes, gantries for cranes, equalizers, hoisting drums

multi-sheave blocks, hoisting trestles, bogies, balance beams, conveyor belt drums,

hoisting lugs.


Columns supporting conveyor belt beams, winch drums, frames for winches and drive

systems, stiffeners, gear boxes and track vehicles.


Protective casings, ladders and stairs, feed hoppers for conveyors, platforms and cabins.



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6.5. Pipelines


Steam pipes, oxygen pipes, pipelines for corrosive, flammable and toxic media, pipelinesused at low temperatures.

Gas distribution piping.


Cooling water piping, hydraulic piping.

Hydraulic piping must meet the requirements of the Technical Directives

R1 42 01 02 and R1 42 01 08.


Drinking water piping.



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7. REFERENCES

The following references are made in this Corus Standard:

EN

287-1

288-1 to 9

729

1418

10088-3

10204

25817

45001

970NPR-EGKS 2

DIN

462

54111-1

ISO

2553

9002

VM 42 Welding stainless and highly heat-resistant steel (latest issue).

or:

EN DIN

287-1 462

288 54111-1

729

1418

25817

45001

NPR-EGKS 2 ISO

2553

9002

Sheet T 0111

Sheet T 0117

Sheet T 0202

IIW Collection of reference radiographics



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Test procedures RTD:

UT 97001 and 97002

MT 97003

PT 97004

RT 97005

ASME Boiler and Pressure vessel Code Sect. I, II en VIIIASME Boiler and Pressure vessel Code Sect. V art. 5

DVS Katalog, quality classification BS.

ATVK (Mechanical specifications for electric cranes and bulk handling machines)

VM 42 Welding stainless and highly heat-resistant steel (latest issue).

Corus Standard:

S1 30 04 01 Ordering, realisation and inspection for making, repair or

modification of equipment subject to approval of Stoomwezen.

Technical Directive:

R1 42 01 02 Hydraulics-directive for suppliers, erection companies,

managers and users.

Part 2: General

R1 42 01 08 Hydraulics-directive for suppliers, erection companies,

managers and users.

Part 8: Selection piping

RTD: (Rntgen Technische Dienst bv)

Delftweg 144 3046 NC Rotterdam

Tel: +31 (0)10 2088208 Fax: +31 (0)10 4158022

Controlas: (Dutch organisation for specifying welding consumables)

PO box 85745 2508 CK Den Haag

Tel: +31 (0)70 3587301 Fax: +31 (0)70 3502020



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8. STATEMENT

Version 1.0:

This Corus Standard replaces HO standard 00.45.04.001.

Version 2.0:

Par 1.4 supplement to previous text

Par 1.5.2 supplemented with data on required documents

Par 1.9 supplemented

Par 2.2.2 Execution of the test added

Par 3.2.2 Execution of the test fully amended

Par 4.2 supplemented

Chapter 6 amended in List of classification of welding in welding categories

Chapter 9 Appendices non-destructive testing procedures added

Version 2.1Logo changed

Version 3.0:

Non-destructive testing procedure UT-97001 version 3 dated jan.22,2001 added.

Version 4.0:

Par.1.1.1: Scopecompleted.

Par.1.9: Stress relieving extended.

Par.1.10: Clad welding added (including sub paragraphs)

Alterations appendices (non-destructive testing procedures)

UT-97001 point 5.1

Text changed into:The vertical and horizontal linear measures must be checked every three months.

UT-97002

Point 4 changed into:Personnel must be in possession of a valid certificate in accordance with

EN-473, minimal level 1.

Point 6 changed.

MT-97003Point 3 changed into:Personnel must be in possession of a valid certificate in accordance with EN-

473, level MT-2.

PT-97004

Point 4 changed into:Personnel must be in possession of a valid certificate in accordance with EN

473, level PT-2.



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9. Appendices:

Non-destructive testing procedures

9.1. UT-97001 Procedure for ultrasonic examination.

9.2. UT-97002 Procedure for ultrasonic examination for internal

imperfections in steel.

9.3. MT-97003 Procedure for magnetic examination.

9.4. PT-97004 Procedure for penetrant examination.

9.5. RT-97005 Procedure for radiographic examination.



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29/69

Number : UT-97001

Revision : 3 ULTRASONIC EXAMINATION PROCEDURE

Date : 22.01.2001

Page : 4 of 14

6 Range

Calibration on V1/V2

For lamination check at least two backwall echoes shall be visible

For weld examination the range depends on type of weld connection and

material thickness (see chapter 12 table 1 u/i 5)

7. Transfer correction

When reference blocks or DAC scales are used for establishing reference levels a

measurement shall be made of the transfer differences, between test object and block, at

a representative number of locations. These measurements will be established by placing

two probes opposite from each other and comparing the resulting reflections of equal

sweep range.

If the differences are less than 2 dB, correction is not required.

If the differences are greater than 2 dB but smaller than 12 dB, they shall be compensated

for.If transfer losses exceed 12 dB, the reason shall be considered and further preparation of

the scanning surfaces shall be carried out, if applicable.

8. Sensitivity

Lamination check

Second backwall echo of the object to be examined shall be set at 80% screen height

Weld examination

The sensitivity for weld examination will be established by constructing a DAC curve

from the reference block in which two or more, equally divided through thickness, holes

have been drilled with a diameter of 3 mm.

In case no blocks are available the RTD/ASME diagrams will be used. In addition by

wallthicknesses over 50 mm the sensitivity will be increased by 2 dB.

The 100% DAC line is the reference level.


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Number : UT-97001


Date : 22.01.2001

Page : 5 of 14

9. Test sensitivity

During examination, sensitivity shall be increased by a minimum of 6 dB. Evaluation of

indications shall be carried out at normal sensitivity.

10. Calibration control

A calibration control has to be executed:

- at the start and end of each examination- after every 4 hours of examination- when a part of the examination system has been changed

If deviations are found during these checks then the measures shown in the table must be

implemented.

Deviation in

sensitivity

Measure

Deviations < 4 dB The stetting must be corrected for the remainder of the test.

Reduction in the

sensitivity > 4 dB

The setting must be corrected and all tests carried out in the previous period must

be repeated.

Increase in the sensitivity> 4 dB

The setting must be corrected and all indications recorded must be re-tested andre-evaluated.

Deviation in

measuring range

Measure

Deviations < 2 %

in the measuring range

The setting must be corrected for the remainder of the test.

Deviations > 2 %

in the measuring range

The setting must be corrected and all tests carried out in the pervious period must

be repeated.

11. Lamination test

The areas next to the weld across which the corner transducer(s) move (see point 12) must

be tested in advance of the weld test using the straight transducer type B2S-N.

If flaws are detected then their influence on the weld test that is to be performed must be

evaluated and, if necessary, the techniques must be adapted accordingly, for example by

testing from the other surfaces. The consequences of the flaws on the test must be reported

to the client.


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Number : UT-97001


Date : 22.01.2001

Page : 6 of 14

12. Performing the test, transducer movements and test directions

This chapter deals with testing the different types of welds.

12.1 Welds in plates and pipes

For transducer movement A or B for each stroke a minimum overlap of 10 % of thecrystal width must be taken into account and the transducer must be rotated as it is

moved (approx. 10 degrees).

For movements X, Y, W and Z the angle with weld direction is approximately 15degrees.

The tests A,X and Y or B, W and Z must be carried out on both sides of the weld. Ifit is not possible to perform the test from both sides then perform the test from

direction A,X and Y as well as from and from direction B, W and Z.

Tabel 1Thickness of

the parent

material

in mm (t)

Transducers

for

longitudinal

flaws

Transducer

positions

Scanning

distance SZW

Transducer

for transverse

flaws

Transducer position

8 < t < 15 MWB 70

4 MHz

A or B 1,25 x skip MWB 70

4 MHz

(X and Y) or (W and Z)

15 !t < 40 MWB 70 and

60 4 MHz

A or B 1,25 x skip MWB 60 4

MHz.


40 !t < 60 WB 60 and 45

2 MHz.

A or B 1,25 x skip WB 60 and 45

2 MHz.


60 !t !100 WB 60 and 45

2 MHz.

A or B 1,25 x skip WB 60 and 45

2 MHz.

(C and D) of (E and F)

B

SZW

D

C

A

X

Y

(B)

(W)

(Z)

(E)

(F)

AX,Y

W,Z


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Page : 7 of 14

12.2 T (K)- connections in constructions

For transducer movement A or B for each stroke a minimum overlap of 10 % of thecrystal width must be taken into account and the transducer must be rotated as it is

moved (approx. 10 degrees).

For movements X, Y, W and Z the angle with weld direction is approximately 15degrees.

When tested with a straight beam probe from position C for t < 15 mm the probeshall be moved opposite the centre of the weld and for t > 15 mm the probe shall be

moved over distance c.

Tabel 2

Thickness of

the parent

material

in mm (t)

Transducers

for

longitudinal

flaws

Transducer

positions

Scanning

distance SZW

Straight

probe

Transducer

for transverse

flaws

Transducer

position

8 !t < 15 MWB 70

4 MHz

A or B 1,25 x skip MB4S-N MWB 70

4 MHz

(X and Y) or

(W and Z)

15 !t < 40 MWB 60

4 MHz

A and B 1,25 x skip MB4S-N MWB 60

4 MHz

(X and Y) or

(W en Z)

40 !t !100 WB 60 en 45

2 MHz.

A and B 0,75 x skip B2S-N WB 60 en 45

2 MHz.

(X and Y) or

(W and Z)

X(W) Y(Z)

A (B)

BA

C

C

C

Cross-section Side view


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Number : UT-97001


Date : 22.01.2001

Page : 8 of 14

12.3 L- connections in constructions

For transducer movement A or B for each stroke a minimum overlap of 10 % of the crystalwidth must be taken into account and the transducer must be rotated as it is moved (approx.

10 degrees).

For movements X en Y the angle with weld direction is approximately 15 degrees.

When tested with a straight beam probe from position C the probe shall be moved overdistance c as a minimum.

Tabel 3

Thickness of

the parent

material

in mm (t)

Transducers

for

longitudinal

flaws

Transducer

positions

Scanning

distance

SZW

Straight

probe

Transducer for

transverse flaws

Transducer

position

8 !t < 15 MWB 70

4 MHz

A or B 1,25 x skip MB4S-N MWB 70

4 MHz

X en Y

15 !t < 40 MWB 70 en

60 4 MHz

A or B 1,25 x skip MB4S-N MWB 60 and 45

4 MHz

X en Y

40 !t !100 WB 60 en 45

2 MHz.

(H or A)

and B

0,75 x skip B2S-N WB 60 and 45

2 MHz.

D en E

X Y

B(A)

C

Side view

H

ED

H

C

C

H

A B

t

Cross-section


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Number : UT-97001


Date : 22.01.2001

Page : 9 of 14

12.4 Set in nozzle welds

For transducer movement A, B, D and E for each stroke a minimum overlap of 10 % of thecrystal width must be taken into account and the transducer must be rotated as it is moved

(approx. 10 degrees).

For movements X, Y, W and Z the angle with weld direction is approximately 15 degrees.

If possible the examination from inside the nozzle will be carried out, positions C, D and E.

Position C will be moved over distance c and D and E will be moved over distance d and e

respectively.

Tabel 4

Thickness of

the parent

material

in mm (t)

Transducers

for

longitudinal

flaws

Transducer

positions

Scanning

distance SZW

Straight

probe

Transducer

for transverse

flaws

Transducer

position

8 !t < 15 MWB 70

4 MHz

A or

D

1,25 * skip or d MB4S-N MWB 70

4 MHz

X and Y

15 ! t < 40 MWB 60

4 MHz

A or

D and E

1,25 * skip or

d + e

MB4S-N MWB 60

4 MHz.

X and Y

40 !t < 60 WB 60

2 MHz.

A or B D

and E

1,25 * skip

d + e

MB4S-N WB 60

2 MHz.

(X and Y) and

(W and Z)60 !t !100 WB 60 en 45

2 MHz.

A and B

D en E

0,5 * skip

d + e

B2S-N WB 60 and 45

2 MHz.

(X and Y) and

(W and Z)

D,E

C

A

(B) X

(W)

Y

(Z)

c

e

d

D

C

E

B

A

Cross-section Top view

Shell

Nozzle


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Number : UT-97001


Date : 22.01.2001

Page : 10 of 14

12.5 Set-on nozzle welds

For transducer movement A or B for each stroke a minimum overlap of 10 % of the crystal

width must be taken into account and the transducer must be rotated as it is moved (approx.

10 degrees).

For movements X en Y the angle with weld direction is approximately 15 degrees.

The examination from the inside of the nozzle, positions B, X and Y, will be executed if

accessible.

Tabel 5

Thickness of

the parent

material

in mm (t)

Transducers

for

longitudinal

flaws

Transducer

positions

Scanning

distance

SZW

Straight

probe

Transducer

for

transverse

flaws

Transducer

position

8 !t < 15 MWB 70 + 60,4 MHz

A 1,25 x skip NA MWB 704 MHz

X and Y

15 !t < 40 MWB 60 + 70,

4 MHz

A 1,25 x skip MB4S-N MWB 60

4 MHz.

X and Y

40 !t < 60 WB 60 + 45

2 MHz.

A and B 1,25 x skip

0,5 x skip

MB4S-N WB 60 + 45

2 MHz.

X and Y

60 !t !100 WB 60 + 45

2 MHz.

A and B 1,25 x skip

0,5 x skip

B2S-N WB 60 + 45

2 MHz.

X and Y

Dwarsdoorsnede Bovenaanzicht

A

B

x,y A

B

XY


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Number : UT-97001


Date : 22.01.2001

Page : 11 of 14

13. Onderzoeksvolume

During the test at least the weld and 10 mm on both sides of the weld must be tested.

A 10 mm 10 mm

A = width of the test volume

14. Determination of the length of indications

The length of an indication is determined by recording the distance over which the

amplitude of the echo is above the evaluation level.

The evaluation level is 33% DAC (= -10 dB)

15. Evaluation of indications

15.1 Noise level

During the test the noise level must remain at least 12 dB below the evaluation level (33%DAC) (in other words a noise level of < 8% DAC). If the noise level is higher then these

areas are to recorded in the report as not tested.

15.2 Evaluation and recording indicationsStep 1:

All indications with a level of > 33% DAC must be tested further and then characterised

as flat or volumetric flaws. This means that indications of < 33% DAC are not to be taken

into consideration.

Step 2:

All weld flaws, characterised as flat, are to recorded by their position, length and echoheight. The type of flaw is also to be determined: crack (E), lack of fusion (C) or

incomplete penetration (D).Step 3:

All volumetric flaws above 50% DAC are to be recorded by their position, length and

echo height for examination with acceptance level 2 and above 80% DAC for examination

with acceptance level 3.The type of flaw is also to be determined: gas (A), slag (B)Step 4:

Evaluate the permissibility of all indications that are recorded for acceptance level 2

according to 15.3 and for acceptance level 3 according to 15.4.


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Date : 22.01.2001

Page : 12 of 14

15.3 Acceptance level 2

Flat flaws are not permitted, irrespective of their length.

The acceptance for volumetric flaws is shown in the figures below for individuallongitudinal and transverse flaws, in relation to material thickness. For accumulative flaws

and flaws in line see 15.5.

= Acceptance level for volumetric flaws

--------- = Evaluation level

Reference level : 0 dB (=100% DAC)

Registration level for volumetric indications = Reference level 6dB

0

2

-2

-4

-6

-8

4

6

-10

-12

1t0.5t 1.5t 2t

8 mm =< t =< 15 mm

lengte van de indicaties

relatieveechoamplitude

0

2

-2

-4

-6

-8

4

6

-10

-12

1t0.5t 1.5t 2t

15 mm =< t =< 100 mm


relatieveechoa

mplitude

dB

dB

-14

-14


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Number : UT-97001


Date : 22.01.2001

Page : 13 of 14

15.4 Acceptance level 3

Flat flaws are not permitted, irrespective of their length.

The acceptance for volumetric flaws is shown in the figures below for individuallongitudinal and transverse flaws, in relation to material thickness. For accumulative flaws

and flaws in line see 15.5.

= Acceptance level for volumetric flaws

--------- = Evaluation level

Reference level : 0 dB (=100% DAC)

Registration level for volumetric indications = Reference level 2dB

0

2

-2

-4

-6

-8

4

6

-10

-12

1t0.5t 1.5t 2t

8 mm =< t =< 15 mm


relatieveechoamplitude

0

2

-2

-4

-6

-8

4

6

-10

-12

1t0.5t 1.5t 2t

15 mm =< t =< 100 mm


relatieveechoa

mplitude

dB

dB

-14

-14


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42/69

Number : UT-97002


Date : 18.02.2000

Page : 3of 5

8 Couplant

A waterbased couplant is preferable.

9 Range

The range with a single crystal probe shall be adjusted in such a way that at least two

backwall echoes appear on the screen. With a double crystal probe, at least the minimum

thickness of the steelplate shall be adjusted.

10 Sensitivity

- steelplate examination - Class S3 see table 1

- material edge examination - Class E4 see table 2

Table 1: plate surface

Acceptable clusters of discontinuitiesClass Area of Unacceptable individual

discontinuity mm2

Area1)

mm2 Maximum densitynot greater than

S3 Inclusions which a reflection

> DAC for a cylindrical

hole 8 mm

N3(between 5 mm

and 8 mm)

10 in the most

populated

1 m x 1 m square

a) Dimensions of each discontinuity within the assessed

Table 2: Material edge

Permissible individual

discontinuity size

Class

Maximum

Dimension

Lmax

mm

Maximum

Area

Smax

Mm

2

Minimum

Discontinuity

dimension

Considered

Lminmm

Permissible

number of

discontinuities

smaller than the

maximum size and

longer than

Lminper1 m length

E4 20 50 10 2


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Number : UT-97002


Date : 18.02.2000

Page : 4of 5

11 Sensitivity setting weld preparation examination

This examination will only be carried out when the plates already have been

cut and the welds preparations are machined.

- Sensitivity 5 mm ERG according to the A.V.G.-system.

12 Test sensitivity

During examination, sensitivity shall be increased by a minimum of 6 dB. Evaluation of

indications shall be carried out at original sensitivity.

13 Registration level

Plate examination : see table 1.

Weld preparation examination : see table 2.

Corus Weldinspection Department assesses the report for the acceptability of the

discontinuities.

14 Report form

The standard RTD report forms shall be used and be filled out completely.


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Number : UT-97002


Date : 18.02.2000

Page : 5of 5

Statement:

1. See table 2 for the value of the edge zone width2. Scan line3. Edge zone4. Principal rolling direction5. Flat product

6. Width7. Length

Dimensions of each discontinuity in the cluster in question


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47/69

Number : MT-97003

Revision : 2 MAGNETIC PARTICLE EXAMINATION PROCEDURE

Date : 21.02.2000

Page : 3of 5

4 Surface condition

The object to be examined at the location of the test shall be dry and free of oil, dirt,

weld spatter, rust, loose scale, loose paint or foreign matter that might interfere with

the examination.

If can be necessary to improve the surface condition, for example with sandpaper or

local grinding to allow a secure interpretation of the indications.

The temperature of the surfaces to be examined shall be 60C as a maximum.

5 Equipment and method of examination

5.1 A. Yoke magnet alternating current (AC)

In accordance with CP-31201

B. Prode Magnet unit alternating current (AC) coil methodIn accordance with CP-31208

5.2 Accessories

- Inspection ink

Black inspection ink, oil or water based.

The inspection ink has to be in accordance with CP-31203.

- Berthold indicator

The Berthold indicator shall be used to determine the direction of the field. Also the

inspection ink can be assessed for its adequacy.

The NDT technician shall be inpossession of the indicator and shall use the indicatoron a regular basis. In any case once a day and in case of relevant changes in the

examination circumstances.


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Number : MT-97003


Date : 21.02.2000

Page : 4of 5

6 Current to be used

6.1 (A) Examination-technique yoke magnet

Yoke magnets shall have a lifting power capacity of at least 4,5 kg.

6.2 (B) Examination with prodequipment

The amperages to be used shall > 5 A/mm prod spacing.

6.3 Coil technique

The amperages to be used shall be in accordance with following sketch.

N = number of coils

I = amperage

a = distance between the weld and the coil or cable

7 Direction of field

Two independant examinations shall be made in each area being tested.

The second examination shall be made with the lines of magnetic flux approximately

perpendicular to the first examination. The second examination may be carried out

using a different magnetising technique.


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Number : MT-97003


Date : 21.02.2000

Page : 5of 5

8 Examination coverage

The examination shall be carried out with sufficient overlap to assure that all areas to

be examined will be 100% examined with the required sensitivityopi. See following

sketch.

9 Application of test ink (continuous method)

The test ink is applied simultaneously with the appliance of the field and the

appliance will be continued after appliance of the testink to create the forming of theparticles.

10 Evaluation of indications

Not all indications are necessarily relevant indications. Excessive surface roughness,

magnetic permeability variations may produce similar indications.

Each doubtful indication shall be re-examined to determine if relevant

discontinuities are present or not.

11 Acceptance standard for the indicationsDimensions in mm

Acceptance levelType of indication

1

Linear indication

l = length of the indication l 1,5

Not-linear indication

d = dimensions of the primary axis d 2

12 Report form



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Number : PT-97004

Revision : 2 LIQUID PENETRANT EXAMINATION PROCEDURE

Date : 21.02.2000

Page : 3 of 5

5 Surface condition

All items to examined shall be free of dirt, oil, paint, weld spatter, rust, scale loose

paint or foreign matter that might interfere with the examination.

6 Penetrant types to be used

Colour contrast, solvent or water removable.

7 Type penetrant

Penetrant materials from the same brand.

8 Temperature of workpiece

Between 10and 55celcius.

9 Method of examination

9.1 Pre-cleaning

All surfaces to be examined shall be thoroughly cleaned. In case of inspection of

welds, the weld and both sides of the material to 25 mm shall be well cleaned.

9.2 Application of penetrant

After drying the penetrant may be applied by dipping brushing or spraying. If the

penetrant does not stay in an even layer, then pre-cleaning shall be repeated.

- dwell time minimum 20 minutes.

Warning:

Emphatically we point out that the use of aerosol containers in closed areas is

dangerous and therefor forbidden.


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Number : PT-97004


Date : 21.02.2000

Page : 4 of 5

9.3 Removal of penetrant

Excessive penetrant shall be removed sequently as follow:

a. Dry cloths

b. Cloths dampened with solvent or water

c. Dry cloths.

9.4 Application of developer

After drying, apply a very thin even layer.

The surface of the workpiece should be just visible.

- develop time minimum 20 minutes.

9.5 Examination

Start examination when developer has dried and continue until development time has

lapsed (minimum 20 minutes).

10 Evaluation of indications

- Not all indications are necessarily relevant indications, localized surface

irregularities due to machining marks or other surface conditions, may produce

false indications.

- Any questionable or doubtful indications shall be re-examined to determine

whether or not they are relevant.


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Number : PT-97004


Date : 21.02.2000

Page : 5 of 5

11 Acceptance levels of indicationsDimensions in mm

Acceptance levelType of indication

1

Linear indication

l = length of the indication l 2

Not-linear indication

d = dimensions of the primary axis d 4

12 Clustered indications

Indications in-line shall be assessed as one, continuing indication, if the distance is

smaller as the marndimension of the smallest indication.

13 Report form



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Number : RT-97005

Revision : 2 RADIOGRAPHIC EXAMINATION PROCEDURE

Date : 21.02.2000

Page : 2 of 14

1 Scope of examination

This procedure describes the method and assessment for the radiographic weld

examination.

For the assessment of the radiographs the following numbers of the EN 25817 will be

evaluated: 1, 2, 3, 4, 5, 6, 7, 8 and 9.

2 Extent of examination

The extent of the examination will be established by Hoogovens or the contractor.

The category of welding may be 1, 2, or 3.

Welding category 1:

Percentage of inspection 100%.

Assessment criteria according EN 25817 level B

Welding category 2:

All weld crossings, completed up to at least 10% of the total amount of welds. This

completion must be of the same welding category, 10% erection welds and 10%

prefab welds. The remaining welds will be pointed out by a weld inspector.

Assessment criteria according EN 25817 level C

Welding category 3:

No NDE dictated.

On a request of Hoogovens' Welding inspection welds can be dictated forexamination.

Assessment criteria according EN 25817 level D


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Number : RT-97005


Date : 21.02.2000

Page : 3 of 14

3. Equipment

3.1 X-ray equipment, directional type

Make : Balteau, Andrex or Seifert

Energy range : 10 300 keV

Effective focal spot size : 2 4 mm

3.2 X-ray equipment, orthogonal type

Make : Balteau, Andrex or Seifert

Energy range : 160 300 keV

Effective focal spot size : 3 5 mm

3.3 Gamma-ray equipment

Make : Techops

Ir-192 : Effective source size < 2,1 mmCo-60 : Effective source size between 2 and 4 mm

4. Films, screens, density and diagnostic film length

4.1 Films

The films used are conform EN 584-1: C3 and C4 respectively Agfa D4 and D5.

The films must be free of defects that may disturbed the evaluation of the results.

Such blemishes include but are not limited to:a. repairs to radiographs owing to processing;

b. scratches and dirtiness;c. static marks;d. false indications due to defective screens.


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Number : RT-97005


Date : 21.02.2000

Page : 4 of 14

4.2 Screens

Radioactive

source

Screen thickness

front/back

in mm

Material

X-ray

Ir-192

Co-60

0,027

0,125

0,5

Pb

Pb

Cu or SS

The thickness of the screens may be less if the required sensitivity keeps

demonstrable.

4.3 Density

Radiographs shall be within the density limits 2.3 and 3.5.

A tolerance of 0.1 in density shall be used for variations between densitometer

readings. Only films with a maximum fog density of 0.3 shall be used.

4.4 Diagnostic film length

The diagnostic film length will be specified by: the number of exposures, the

demonstrated quality and the density limits.

4.5 Film coverage

The film coverage shall be within the diagnostic film length. If the diagnostic film

length is more than the film size used the coverage shall be at least 20 mm.


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Number : RT-97005


Date : 21.02.2000

Page : 5 of 14

5. Image Quality Indicator (IQI)

5.1 IQI conform EN 462-1

Type and wire material of IQI.

Code en type Wire number Wire length

in mm

Wire material Material group

EN 1 Fe

EN 6 Fe

EN 10 Fe

EN 13 Fe

1 to 7

6 to 12

10 to 16

13 to 19

50

50 or 25

50 or25

50 or 25

unalloyed

steel

iron

5.2 Required image quality for the single wall technique (SW)

Single wall technique and theIQI on source side

Required quality wire diameter

Nominal wall thickness in

mm

Class B mm

1,5

2,5

4

2,5

4

6

W18

W17

W16

0,063

0,080

0,100

6

8

12

8

12

20

W15

W14

W13

0,125

0,16

0,20

20

30

35

30

35

45

W12

W11

W10

0,25

0,32

0,40

45

65

65

120

W9

W8

0,50

0,63

If Iridium 192 is used the required image quality within 12 to 40 mm shall be 1 wire

number lower.


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Number : RT-97005


Date : 21.02.2000

Page : 6 of 14

5.3 Required image quality for the double wall double image technique (DW-DI)

Double wall Double image technique

and the IQI on source sideRequired quality Wire diameter

Penetrated thickness in mm class B mm

1,52,5

4

2,54

6

1817

16

0,0630,080

0,100

6

8

12

8

12

20

15

14

13

0,125

0,16

0,20

20

30

35

30

35

45

12

11

10

0,25

0,32

0,40

45 65 9 0,50

5.4 Required image quality for the double wall single image technique (DW-SI)

Double wall single image technique and

IQI on film sideRequired quality Wire diameter

Penetrated thickness in mm class B mm

1,52,5

4

2,54

6

1817

16

0,0630,080

0,100

6

12

18

12

18

30

15

14

13

0,125

0,16

0,20

30

45

55

45

55

70

12

11

10

0,25

0,32

0,40


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Date : 21.02.2000

Page : 7 of 14

5.5 Number of IQI's

Weld in flat plates

At least one IQI across the weld with the thinnest wire in the thickest part to be

examined.

Welds in curved plates

Circumferentional welds examined in one exposure at least three IQI's equally spaced

across the weld. The maximum distance between two IQI's shall be less than 1 m.

Double wall single image technique (DW-SI)

One IQI just within the diagnostic film length.

Double wall double image technique (DW-DI)

With the DW-SI technique and a diameter smaller than 50 mm, one IQI parallel next

to the weld and perpendicular to the pipe axis in such a way that the IQI image will

not be projected in the weld area.

5.6 IQI location

The IQI shall be placed on the source side of the object to be examined.

If the source side is inaccessible the IQI will be placed on film side. A lead letter "F"

will be placed beside or on the IQI.

In general the IQI will be placed across the weld, except if the diameter is smaller than

50 mm.

6. Energy selection

The choice of the radiation source will be stipulated by the object thickness. For adouble wall technique the penetrated thickness is the sum of two walls.

6.1 X-ray up to 300 kV

The maximum kV-setting for steel: 100 kV + 8 kV/mm

The maximum kV-setting shall be raised with a maximum of 50 kV when the

reinforcement or thickening may influence the interpretation of the radiographs.


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6.2 Thickness range for radioactive sources

Gamma source Steel

Ir-192 20 to 100 mm

Co-60 60 to 150 mm

The thickness limitation will be reduced when the radiographic techniques useddemonstrate that the required radiographic sensitivity has been obtained

7. Film-focus distance

The minimum film focus distance (Fmin) shall be:

10x the thickness to be inspected. This calculation will be used for a 2 mm radiation

source.

In general : Fmin= B x 5 x (thickness to be inspected)

B = Radiation source size in mm

Fmin = Minimum Film focus distance in mm

8. Film identification and marking

8.1 Film identification

The identification may consist of:

a. order number or object number;b. weld number;

c. indication after a repair, R1 for first repair, R2 for second repair, etc.

8.2 Marking

In general fixed markers will be used to localise any radiograph. When the shape of

the material doesn't allow marking by hammering other method will be used, e.g.

yellow chalk.

For the radiographic inspection of circumferential welds measuring tape or overlap

ciphers will be used. When measuring tape is used at least one distance indicator shall

be visible on the next radiograph. The start and a direction indicator will be marked onthe object.


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Number : RT-97005


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Page : 9 of 14

9. Radiographic set-ups and techniques

9.1 Direction of radiation

The direction of the central beam of radiation will be centred on the area of interest. If

possible or practical, a single wall technique will be used. When a single wall

technique is not practical a double wall technique shall be applied.

9.2 Single wall technique

9.3 Double wall single image technique (DW-SI)

For the number of exposures for technique 13 see page 11


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9.4 Double wall double image technique (DW-DI)

For circumferential welds up to 75 mm diameter, if practical.

Elliptical projection Superimposed

10. Number of exposures

The number of exposures of circular welds in steel are given in the next two tables.

Table 1 for X-ray equipment and table 2 when Iridium 192 is used.

The code 2/3 means: 2 exposures with an elliptical projection (set-up 11) or 3

exposures with the superimposed technique at 600or

1200to each other (set-up 12), only when the ellipticalprojection is not practical.

The code X/XX means: X exposures with the DW-SI technique or

XX exposures with the DW-DI technique


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Number : RT-97005


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Page : 11 of 14

Number of exposures when an X-ray tube is used

table 1

mm 5S 10S 10 20 30 40S S 40 60 80S XS 80 100 120 140 160 XXS1/

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