ISO 18954:2026

This document specifies a test method to determine parameters of bolt tightening procedures for pretensioned bolted connections to be used in structural steelwork. The methods to establish bolt tightening procedures given in this document are applicable to pretensioned bolted connections for which no approved tightening parameters exist in national or international standards. For example, in cases where bolting assemblies have to be tightened by turning the head instead of the nut, when conditions deviate from a given harmonized standard for pretensioning of bolting assemblies, or when stainless steel bolting assemblies are to be pretensioned. In these cases, tightening parameters as well as tightening procedures can be determined with the use of the Bolt Tightening Qualification Procedure (BTQP) given in this document.