PROCEDURE FOR HARDNESS TESTING

PAGE 00638-04-HT-MAG-QI

PROCEDURE FOR HARDNESS TESTING

Section No.CONTENTS

1.0SCOPE

2.0REFERENCE DOCUMENTS

3.0PERSONNEL

4.0EQUIPMENT & ACCESSORIES

5.0Surface Preparation

6.0Extent of Examination

7.0Methods of Measurement

8.0Acceptance Criteria

9.0Records

ANNEXURE 1 HARDNESS TEST REPORT

1.0 SCOPE

1.1This procedure details the requirements for measuring the hardness of metallic materials having a thickness of 5mm and above using portable hardness testing equipments.

2.0REFERENCE DOCUMENTS

ASTM A956 Standard Test method for Leeb Hardness Testing of Steel Products.

ASTM E140 Standard for the Conversion of hardness units.

ASME B31.1 Code for Chemical Plant and Refinery Piping.

ASME SEC VIII Code for Boiler and Pressure Vessel.

NACE MR 0175 (Latest Edition)

3.0PERSONNEL

3.1The personnel using this procedure shall be suitably qualified and trained in the use of the equipment listed in this document.

4.0EQUIPMENT & ACCESSORIES

4.1Any one of the following equipment shall be used for measuring the hardness of metallic materials having a thickness of 5mm and above.

Equipment with Dyna D Impact device

5.0SURFACE PREPARATION

5.1The surface temperature of the part to be measured shall be between 15C and + 50C.

5.2The surface shall be free of coatings (both metallic / nonmetallic), rust, scale, oil, grease, oxides and all other foreign materials.

5.3The location of the measurement area shall be smoothly ground to a finish of not less than 220grit using silicon carbide or alumina oxide grinding papers for the indentation and proper seating of the impact device.

6.0EXTENT OF EXAMINATION

6.1The percentage of hardness readings to be taken shall be verified against the relevant drawing or client specification.

6.2When measuring the hardness on piping components in excess of 50mm in diameter, four clock positions shall be measured. All other components (Structural) shall be tested on at least five locations minimum or ten locations per square meter as described by the client.

7.0METHODS OF MEASUREMENT

7.1EQUIPMENT WITH D IMPACT

7.1.1Calibrate the instrument prior to commencing any hardness testing on the calibration block provided and verify the HL values are within the specified tolerance. The frequency of calibration shall be after every 1000 readings of continuous use provided the unit is not switched off. Calibration should also be performed after changing the batteries or if any malfunction is suspected.

7.1.2Select the material to be tested on the instrument (within the nine groups of materials), select the hardness unit, preferably HV, then select other parameters such as average and conversion standard. The equipment is now prepared for testing. There is no need to note the angle of impact device, this is self detected along with gravitational force and is compensated for by the machine.

7.1.3Since, this equipment is operating under the rebound principle, impact support is required for small components between 0.05 5kg. When the thickness of component is between 5-20mm (e.g., pipe spool) no additional support is required. If the component is not rigid, additional support is required to avoid springing of the internal impact device. If the component is above 20mm thickness no additional support is required.

7.1.4After surface preparation place the loaded instrument gently on the surface of the part to be tested and release the button recording the reading.

8.0ACCEPTANCE CRITERIA

8.1

9.0

9.1The acceptance criteria shall be as per the referencing CODE section or Client specification, as applicable RECORD

All the readings shall be recorded as per Annexure 1