Nuts & bolts

Nuts & bolts

Engineering science related to nuts, bolts, threaded fasteners and tightening techniques.

Contributors in Nuts & bolts

Nuts & bolts

Steel fasteners exposed to hydrogen can fail prematurely at a stress level well below the materials yield strength. Hydrogen embrittlement occurs in fasteners usually as a result of the part being ...

stress area

Machine tools; Nuts & bolts

The effective cross sectional area of a thread when subjected to a tensile force. It is based upon a diameter which is the mean of the pitch (or effective) and the minor (or root) diameters of the ...

unified national extra fine (UNEF)

Machine tools; Nuts & bolts

UNEF is a Unified thread form with a very fine (small) pitch that are typically used on instruments and parts requiring a fine adjustment.

pooching

Machine tools; Nuts & bolts

Pooching is a term sometimes used to describe the effect of the area immediately surrounding a tapped hole being raised up as a result of the tension from the stud. Tapped holes are often bored out ...

major diameter

Machine tools; Nuts & bolts

This is the diameter of an imaginary cylinder parallel with the crests of the thread; in other words it is the distance from crest to crest for an external thread, or root to root for an internal ...

class of fit

Machine tools; Nuts & bolts

The Class of Fit is a measure of the degree of fit between mating internal and external threads. Three main Classes of Fit are defined for metric screw threads: * Fine: This has a tolerance class of ...

high strength friction grip bolts

Machine tools; Nuts & bolts

Sometimes abbreviated to HSFG bolts. Bolts which are of high tensile strength used in conjunction with high strength nuts and hardened steel washers in structural steelwork. The bolts are tightened ...