E... Glossary of Fastener and Fixing Terminology
GLOSSARY ALPHA LOCATOR
This is the diameter of an imaginary cylinder coaxial with the thread, which has equal metal and space widths. It is often referred to as pitch diameter. Sometimes referred to as the simple effective diameter to differentiate from the virtual effective diameter.
EFFECTIVE NUT DIAMETER
Twice the effective nut radius.
EFFECTIVE NUT RADIUS
The radius from the centre of the nut to the point where the contact forces, generated when the nut is turned, can be considered to act.
The maximum load per unit of area that may be applied without producing permanent deformation. It is common practice to apply the load at a constant rate of increase and also measure the increase of length of the specimen at uniform load increments. The point at which the increase in length of the specimen ceases to bear a constant ratio to the increase in load, is called the proportional limit.
Electroplating is carried out in a water-based solution containing a chemical compound of the metal to be deposited. The parts to be plated are immersed in the plating bath and an electrical current is passed through which causes the plating metal to precipitate out and to be deposited on the component parts in the plating bath. Coating
A relatively thin, hard coating that can be applied to threads and deposited uniformly. Bright metallic in appearance this coating has excellent resistance to wear and corrosion. Coatings
ELEVATOR BUCKET BOLT
A flat, plain, circular countersunk head bolt with a square neck to prevent rotation. Product
The increase in length of a test specimen after rupture in a tensile test, expressed as a percentage of the original length.
Localised plastic metal deformation which occurs in the vicinity of clamped fasteners or in the fastener threads. . Embedding is local metal deformations that occur under the nut face, in the joint faces and in the threads as a result of plastic flattening of the surface roughness. This occurs even when the loading is below the yield point of the bolt or limiting surface pressure of the joint material and is the result of the real area of contact between surfaces being less than the apparent area.
A bar threaded at both ends with various fits of thread and combinations of thread length. Product
ENVIRONMENTALLY ASSISTED CRACKING (EAC)
A process that can occur with the use of high strength steel fasteners in which crack initiation and growth occurs in the fastener at a comparatively low stress level as a result of interactions that occur with the environment. Hydrogen is suspected of causing EAC in high strength steel fasteners, the hydrogen being produced as a result of chemical reactions (galvanic corrosion in a moist environment) or being present from a plating process that may have been applied to the fastener.
A piece generally used to join a plate or shield, to cover or protect softer or more delicate materials or actions. Product
EXTERNAL FORCE OR LOAD
Forces exerted on a fastener as a result of an applied loading to the joint.
A screw thread which is formed on an external cylinder, such as on bolts, screws, and studs.
A bolt having a head in the form of an open or closed anchor ring, or of a flattened and pierced section, with or without a collar or shoulder under the head. Product
effective diameter andeffective nut diameter along with effective nut radius and elastic limit are only a few of the technical terms on this fastener site. electroplating-electroless-nickel-elevator-bucket-bolt-elongation-embedment-engineers-stud-environmentally-assisted-cracking-(eac)-escutcheon-pin-eye-bolt-external-force-load-external-thread