hardness procedure.doc

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Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

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No.NBTC M3 QC HRDT 22.0 Cont. No.: 03UT02-053

Rev. No. 4 Page 2 of7

TITLEPROCEDURES FOR HARDNESS TESTING.

TABLE OF CONTENTS

SECTION TITLE PAGE

1.0 SCOPE 3

2.0 REFERENCES 3

3.0 DEIFNITIONS 3

4.0 PROCEDURE 3~4

4.1 EQUIPMENT 3

4.2 METHOD 3~4

4.3 SURFACE PREPARATION 4

4.4 EQUIPMENT CALIBRATION 4

4.5 MEASURING 4

4.6 EXTENT OF TESTING 4~5

4.7 REPORTING 5

4.8 ACCEPTANCE CRITERIA 5

4.9 SAFETY 5

5.0 ATTACHMENTs 5

6.0 Response to Owners Reply for K053 RFI 083 6

7.0 Checking the Magnetic Field by using Gauss Meter 7

NBTC-M3-HT-12.01 (Hardness Test Report)

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1.0 SCOPE

This document describes the minimum requirements for hardness testing of metals using

EQUOTIP 3 with D type Impact Device D. This document has specific reference to the

project- OL2K Mechanicalworks (M3). This procedure is applicable to production welds. This

procedure is not applicable to test welded PQR specimen.

2.0 REFERENCES

2.1 ASME SecV -Non-Destructive Examination

2.2 ASME B 31.3 -Chemical Plant and Petroleum Refinery Piping.

2.4 NACE MR-0175 -Sulfide stress cracking resistance metallic material for oil field

equipment.

2.5 K85-6500-01 -Additional requirement to Project specification (G8S- 6500-01)

2.6 ASTM A956 - 06 -Standard test method for leeb hardness testing.

3.0 DEFINITIONS

3.1 ASME - American society of mechanical engineers3.2 ASNT - American society for non-destructive testing.

4.0 PROCEDURE

4.1 EQUIPMENT

Testing shall be performed using the portable test equipment EQUOTIP 3 with Impact

device type 'D'.

4.2 METHOD

When a local hardness check is required on any welds of ferritic steels.

Prepare the test locations by using the 200 grit grinding wheel or disc for surface finish

63 in. (2m). The testing position is to be adjusted to the required testing position and

Impact device to be released. 5 (Base Metal, Heat affected Zone, Weld Metal, Heat

affected Zone, Base Metal) readings shall be taken to constitute and average of all the

readings is one value in an area of 1 sq in. Readings shall be noted in the Hardness Test

Report - (NBTC-M3-QF-14.01, Rev-3, and Date 02-08-2007)

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4.2.1 A spring loaded impact device hits the surface to be tested and rebounds. The impact and

rebound velocities are measured in a contact less manner at the precise moment, where

the spherical test tip is located at approximately 1 mm from the test surface.

4.2.2 The ratio between the two velocities is determined electronically and the hardness of the

material is given digitally for immediate reading.

4.2.3 For each spot of hardness test, a minimum of 3 readings shall be taken and average is

calculated as the hardness value of that spot.

4.3 SURFACE PREPARATION

4.3.1 The specimens shall have smooth surface to obtain correct values. Corroded surface,

roughly ground surface etc. may give erroneous measurements.

4.3.2 While preparing the surface for hardness test, over heating shall be avoided.

4.3.3 Light weight specimens shall be rigidly held with non-yielding supports to avoid flexing

during the impact load

4.3.4 All the spots shall be grind to make smooth surface with 200 grit grinding wheel for 63

in (2m).

4.4 CALIBRATION

4.4.1 Equipment shall be calibrated once in a year and calibration certificate shall be made

available for record and references. On site calibration shall be performed using a

certified test block provided with the equipment prior to use.

4.4.2 In no case Hardness testing shall be performed if the temperatures are above 380c without

submitting the correction curve.

4.5 MEASURING

4.5.1 Measurements shall be made on properly prepared surfaces of the weld and heat affected

zones.

4.5.2 The temperature of testing area (Joint) shall be checked with digital thermometer and will

be allowed for measuring if and only if temperature is below 380c.

4.5.3 The impact devices shall be internally spring loaded type.

4.5.4 The device is held firm on the test surface and the trigger is activated.

4.5.5 the spring loaded weight hits the test surface and rebounds

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4.5.6 The hardness value is obtained from the digital meter.

4.5.7 The hardness value shall be in HV.

4.6 EXTENT OF TESTING

4.6.1 In general, hardness survey shall be applied to all heat treated production weld in order to

check weather PWHT is applied satisfactorily as required by the standard and

specification. Heat treated socket and fillet weld shall be checked as far as practicable, at

any requirement location. Each repair welds shall be re-tested.

4.7 REPORTING

4.7.1 The hardness value shall be reported in the format as shown in the attached report - form

no (M3-QF-14.01, Rev-3, Date-02-08-2007)

4.8 ACCEPTANCE CRITERIA

4.8.1 The hardness shall be determined as an average of three (3) tests as follows:

4.8.2 The weld itself, the heat affected zone and the base material of each shell section,

Head and nozzle and each longitudinal, girth and nozzle weld with a minimum of one

hardness determination per weld seam.

4.8.3 On carbon steel parts readings shall be made on the inside, on alloy steel parts readings

shall be made on the inside and the outside. All hardness readings to be reported in the

hardness test report.

4.8.4 The maximum allowable hardness's:

Carbon steel: 210 HV10.

Molybdenum and chromium-molybdenum steel: 235 HV10.

4.9 SAFETY

4.9.1 All Requirements of the Contractors Approved HSE Plan and Fire & Safety Regulations

of OL2K Project shall be strictly applied on the all phase of the execution of Hardness

Testing.

5.0 ATTACHMENTs

5.1 Form no (M3-QF-14.01, Rev-3, Date-02-08-2007)5.2 ASTM A 956 06

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5.3 Test Report for Magnetic Fields

5.4 Calibration Certificates

5.5 User Manual

6.0 Response to Owners Reply for K053 RFI 083

1. Type of Hardness tester to be used. EQUOTIP TYPE 3

2. Type of Impact device to be used.Impact Device 'D'

3. Checks to be made prior to verifyingcalibration of the Instrument

Before a Leeb hardness instrument is verified, theinstrument shall be examined to ensure that:

1. The batteries are in good condition and Not

discharged.

2. Impact device spherical is free from dust, dirt,

and any other foreign Matters

3. Impact device tip is free from Cracks or any other

deformation

4. Test Block shall be placed on a firmly supported

base.

4. Type of Calibration Block used and

Frequency of Calibration Test Block 'D'Every time Tested with Test Block for directional

Impact (Once in a year Calibrated with NIST)

5. Requirement to provide a copy of most

recent equipment calibration CertificateYes will be provided (Attached)

6. Minimum Surface Finish required 63in (2 m) by using 200 grit grinding disc or

wheel

7. Surface Curvature Requirements Surface may be either Convex or Concave

Specimen dia not less than 2" (50 mm) for Impact

Device 'G'.

Specimen dia not less than 13

/16" (30 mm) for theother Impact Devices.

8. Maximum allowable residual Magnetic

FieldResidual Magnetic Field shall be less than '4G'.

9. Requirement for item to be tested at rest

(e.g. no Vibration)Test Piece to be at rest.

10. Allowable temperature range pls to take

on

Testing Procedure shall be performed with

temperature of test piece between 400F (40C) and

1000F (380C).

12. Spacing between indentations Two times of diameter of edge to edge in between

two impact points and three time of diameter edge

to edge from the edge of Specimen.

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13. Correction factor when impact device is

not held perpendicular to the test piece.Correction Factor according to the Table 1 given in

the ASTM A 956 for Impact Device 'D'.

14. Samples of reports to be provided

documenting the hardness test results.Attached herewith (Inspection Test Report M3-QF-22.01

Rev.1 dtd 5-7-2007

7.0 Checking the Magnetic Field using Gauss Meter

7.1 The Magnetic Field can be checked with Gauss Meter.

7.2 Range of Gauss Meter NBTC acquired is 200G, 2kG. 20kG

7.3 Manufacturer LAKE SHORE CRYOTRONICS, Inc.

7.4 Model No. 410.

7.5 Sl. No. 43286.

7.6 Procedure for checking the Magnetic Field .

7.6.1 The Joint to be checked or surface to be checked is to be prepared by Buffing or

Sandering.

7.6.2 Buffing of any Ferritic surface area will rise the magnetism of local area for some time.

7.6.3 Sand Wheel cleaning is recommended for checking Magnetism and thus Hardness.

7.6.4 On the Gauss meter.

7.6.5 Check the Low Battery display if any,

7.6.6 Incert the Probe (Axial or Transeverse) with / without extension cable.

7.6.7 Look for the Probe CAL No. Display and should be the same as given on Probes.

7.6.8 Make the reading Zero by using Zero Probe (Soft Key).

7.6.9 Select Auto Range or Range required (0-200G).

7.6.10 Select the measuring Unit required preferably Gauss.

7.6.11 Instrument is Battery sensitive and sensitive reading may be ignored.

7.6.12 Hold the probe around 3 5 mm distance from the Pipe to sense the magnetic field.

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7.6.13 Note down the Max. Reading and can be taken as Max. Residual Magnetism.

7.6.14 User Manual provided can be followed for detailed Instructions.

NBTC-M3-HT-22,REV-4,29-03-2008

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hardness procedure.doc