1. Scope

1.1 This practice covers the procedures to be followed when performing ultrasonic shear and longitudinal wave tests on turbine-generator retaining rings with an inside diameter to wall thickness ratio equal to or greater than 5:1 and with wall thicknesses from 1 to 4 in. (25 to 102 mm).

1.2 Although this practice describes methods of ultrasonically testing retaining rings by either the contact or immersion method, it shall not restrict the use of improved inspection methods as they are developed. It is recognized that techniques for examination and evaluation may be chosen in order to enhance or improve the results or to accommodate variations in procedures, equipment, or capabilities. Considering these characteristics, forgings may be inspected by a combination of both the contact and the immersion methods, as mutually agreed upon between the manufacturer and the purchaser.

1.3 This practice and the applicable material specifications are expressed in both inch-pound units and SI units. However, unless the order specifies the applicable 'M' specification designation SI units, the material shall be furnished to inch-pound units.

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.

ASTM Standards

A288 Specification for Carbon and Alloy Steel Forgings for Magnetic Retaining Rings for Turbine Generators

A289/A289M Specification for Alloy Steel Forgings for Nonmagnetic Retaining Rings for Generators

E127 Practice for Fabricating and Checking Aluminum Alloy Ultrasonic Standard Reference Blocks

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

Keywords

angle beam examination; back-reflection; contact method; generator; immersion method; longitudinal wave testing; nondestructive testing; reference-block; reference-notch; retaining rings; shear wave testing; steel forgings-alloy; turbine; ultrasonic apparatus; ultrasonic couplants; ultrasonic examination;

ICS Code

ICS Number Code 21.060.60 (Rings, bushes, sleeves, collars)

DOI: 10.1520/A0531_A0531M-91R01

ASTM International is a member of CrossRef.