Meaning and Purpose

5.1 The technique described provides an indirect measurement of the thickness of a material section up to a temperature of 93°C[200°F]. Measurements are made from one side of the object without touching the rear surface.

5.2 Ultrasonic thickness measurement is widely used for basic shapes and products of many materials, precision machinations of parts, and determination of process equipment wall thinness caused by corrosion and erosion.

5.3 For recommendations to determine the functionality and limitations of ultrasonic thickness gauges in specific applications, see the cited references.

ASTM E797-2021 Practice for Measuring Thickness by Artificial Ultrasonic Pulse Echo Contact Method

Scope of

1.1 This Practice 2 provides guidance for measuring material thickness using the contact pulse echo method at temperatures not exceeding 93 °C [200 °F].

1.2 This practice is applicable to any material from which ultrasonic waves propagate at a constant velocity throughout the part and from which back-wall reflections can be obtained and resolved.

1.3 This practice is mainly applicable to planar elements with parallel surfaces and has limited applicability for elements with non-parallel or concentric surfaces (per 1.2).

1.4 Units-Values expressed in SI units or ink-pound units should be treated as standard values separately. The values specified in each system are not necessarily the same; Therefore, to ensure compliance with the standards, each system should be used independently of each other and the values of the two systems should not be combined.

1.5 This standard is not intended to address all safety issues, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health and environmental practices and to determine the applicability of regulatory restrictions prior to use.

1.6 This international Standard has been developed in accordance with the internationally recognized standardization principles established in the Decision on Principles for the Development of International Standards, Guidelines and Recommendations issued by the Committee on Technical Barriers to Trade of the World Trade Organization.