ASTM C 1129:2017

1.1 The mathematical methods included in this practice provide a calculational procedure for estimating heat loss or heat savings when thermal insulation is added to bare valves and flanges. 1.2 Questions of applicability to real systems should be resolved by qualified personnel familiar with insulation systems design and analysis. 1.3 Estimated accuracy is limited by the following: 1.3.1 The range and quality of the physical property data for the insulation materials and system, 1.3.2 The accuracy of the methodology used in calculation of the bare valve and insulation surface areas, and the quality of workmanship, fabrication, and installation. 1.4 This procedure is considered applicable both for conventional-type insulation systems and for removable/reuseable covers. In both cases, for purposes of heat transfer calculations, the insulation system is assumed to be homogenous. 1.5 This practice does not intend to establish the criteria required in the design of the equipment over which thermal insulation is used, nor does this practice establish or recommend the applicability of thermal insulation over all surfaces. 1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.7 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.