final tightening torque applied by the torque wrench to the fastener or nut NOTE It is also called the “installation torque”.
3.2.2 clamped parts
regions of the joint that are compressed by the fastener
NOTE Among the clamped parts in a joint, there are always at least two flanges. Other clamped parts that have specialised functions include: washers, spacers, gaskets, etc.
3.2.3 female threaded part
threaded part into which the male threaded part is inserted during fastener installation
NOTE This is normally equivalent to either a nut or a threaded hole flange.
3.2.4 flange
clamped part that transmits loads from a threaded fastener to other regions of the structure
3.2.5 insert
part with a threaded hole, which is embedded in a weaker material in order to increase the loads that can be transmitted through the joint
NOTE It is normally a metallic part.
3.2.6 joint
region of the structure in the vicinity of the threaded fastener
NOTE The dimensional extents of the joint depend on the engineering issues under consideration.
3.2.7 locking device
physical means by which the fastener is held in tension during service and that avoids loosening of the fastener
NOTE Locking devices provide the so called "prevailing torque or self-locking torque or running torque".
3.2.8 male threaded part
threaded part that is designed to fit within a threaded hole NOTE This is normally equivalent to the threaded fastener.
3.2.9 nut
device with an internally threaded hole with the primary functions being the application of tension to the shaft of a threaded fastener and compression to the clamped parts.
3.2.10 nut-tightened joint
joint with a threaded fastener that is tightened by a nut
3.2.11 prevailing torque
torque provided by the locking device NOTE This torque needs to be overcome before the threaded fastener can loosen (also called "running torque or self-locking torque").
3.2.12 prying
change in a fastener's loading caused by a levering action in flexible flanges NOTE It occurs in eccentrically loaded joints, see Section 8.
3.2.13 running torque
See prevailing torque
3.2.14 seating torque
torque that, when applied, produces the compression of the flanges and the preload on the fastener. NOTE: When added to the prevailing torque the resulting torque is called the installation torque.
3.2.15 thread
helical groove on the external surface of a shaft (male thread) or the internal surface of a hole (female thread)
3.2.16 threaded hole flange
flange with a threaded hole into which a threaded fastener is inserted and tightened
3.2.17 threaded hole joint
joint in which the threaded fastener screws into a threaded hole flange
3.2.18 threaded interface
pair of internal and external threads that are designed to fit together allowing relative rotation, and thereby variation of the length of the threaded fastener system
3.2.19 threaded fastener
device that joins multiple parts together by compression of their flanges, where the compression is achieved by rotation of a threaded shaft into a threaded hole
NOTE This definition includes all commonly types of threaded fasteners such as; bolt, screw, threaded pin, etc. Throughout this document, the term threaded fastener is frequently simplified to the word fastener.