ASTM F38-18 - 1.8.2018
 
Significance and Use

4.1 These test methods are designed to compare related materials under controlled conditions and their ability to maintain a given compressive stress as a function of time. A portion of the torque loss on the bolted flange is a result of creep relaxation. Torque loss can also be caused by elongation of the bolts, distortion of the flanges, and vibration; therefore, the results obtained should be correlated with field results. These test methods may be used as a routine test when agreed upon between the consumer and the producer.

Note 1: Test Method B was developed using asbestos gasket materials and at issuance substantiating data were not available for other gasket materials.

 
1. Scope

1.1 These test methods provide a means of measuring the amount of creep relaxation of a gasket material at a predetermined time after a compressive stress has been applied.

1.1.1 Test Method A—Creep relaxation measured by means of a calibrated strain gauge on a bolt.

1.1.2 Test Method B—Creep relaxation measured by means of a calibrated bolt with dial indicator.

1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.

1.3 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

 
2. Referenced Documents

A193/A193M-23

Standard Specification for Alloy-Steel and Stainless Steel Bolting for High Temperature or High Pressure Service and Other Special Purpose Applications

B637-23

Standard Specification for Precipitation-Hardening and Cold Worked Nickel Alloy Bars, Forgings, and Forging Stock for Moderate or High Temperature Service

D3040-81

Practice for Preparing Precision Statements for Standards Related to Rubber and Rubber Testing (Withdrawn 1987)

F104-11(2020)

Standard Classification System for Nonmetallic Gasket Materials

Relaxometer, Method A () A print of this apparatus is available at a nominal cost from ASTM International Headquarters. Order Adjunct No. . Original adjunct produced in 1965.

Relaxometer, Method B () Detailed working drawings of this apparatus are available from ASTM International Headquarters. Order Adjunct No. . Original adjunct produced in 1965.