This practice is intended primarily for the mechanized ultrasonic examination of pipe girth welds used in the construction of gas and oil pipelines. This practice, with appropriate modifications due to changes in weld profile, may also be used to examine repaired welds. Manual techniques such as described in Practice E164 may also be used to examine production or repaired welds. This practice, with appropriate modifications, may also be used to examine other forms of butt welds including long seams.

Techniques used are to be based on zonal discrimination whereby the weld is divided into approximately equal vertical examination sections (zones) each being assessed by a pair of ultrasonic search units. See Fig. 1 for typical zones.

Thicknesses of material examined are normally 7 to 25 mm (0.28 to 1.00 in.) and pipe diameters 15 cm (6.0 in.) and greater but this standard may apply to other thicknesses and diameters if the techniques can be proven to provide the required zonal discrimination.

Examination zones are typically 2 to 3 mm (0.08 to 0.12 in.) in height. For most applications this will require the use of contact focused search units to avoid interfering signals originating from off-axis geometric reflectors and to avoid excessive overlap with adjacent zones.

1. Scope

1.1 This practice covers the requirements for mechanized ultrasonic examination of girth welds. Evaluation is based upon the results of mechanized ultrasonic examination. Acceptance criteria are based upon flaw limits defined by an Engineering Critical Assessment (ECA) or other accept/reject criteria defined by the Contracting Agency.

1.2 This practice shall be applicable to the development of an examination procedure agreed upon between the users of this practice.

1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

CSA Standard

ASTM Standards

E164 Practice for Contact Ultrasonic Testing of Weldments

E317 Practice for Evaluating Performance Characteristics of Ultrasonic Pulse-Echo Testing Instruments and Systems without the Use of Electronic Measurement Instruments

E543 Specification for Agencies Performing Nondestructive Testing

E1316 Terminology for Nondestructive Examinations

ASNT Standard

AIA Standard

API Standard

Keywords

contact focused search units; girth welds; mechanized ultrasonics; Contact focus probes; ECA (Engineering Critical Assessment); Flaw detection; Girth welds; Mechanized ultrasonic testing; Nondestructive evaluation (NDE); Probe methods; Ultrasonic testing; Welding/welds; Zonal discrimination

ICS Code

Citing ASTM Standards

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