Anvil - The part of an installation tool nose assembly used to swage the collar of a lockbolt fastener. Commonly known as a swaging anvil.
Bearing Surface - The head or tail of the fastener which is in contact with the outer surface of the joint material.
Blind Fastener - A fastener that can be installed with access to only one side of the work piece. Please view fastener placing animation.
Blind Hole - A hole which can only be accessed from one end.
Blind Side - The side of the joint which cannot be accessed. E.g. the inside surface of a tubular or box section.
Body - The portion of a breakstem fastener that expands into the parent material.
Body Length - See 'Shank Length'
Breaker Groove - The weakened groove in the stem or pin of a fastener allowing it to break at a pre-determined load.
Breakstem Fastener - A fastener which is installed by gripping and pulling the end of the mandrel/stem. As installation is completed, the end of the stem fractures at the breaker groove and is discarded, leaving the head of the stem in the fastener body.
Broach - (with reference to Avdel® Speed Fastening System) The action of pulling the mandrel though the speed fastener in order to place it. Please view placing animation.
Broach Load - (with reference to Avdel® Speed Fastening System) The force required to pull the mandrel through the speed fastener in order to place it
BSW - Whitworth Thread - An imperial thread form standard, no longer in mainstream use. It is covered by British Standard BS 84.
Bulbing - The physical action of the fastener body swelling (bulbing radially) against the rear face of the joint when placed. Generally found in breakstem fasteners, speed fasteners and threaded inserts. Please view fastener placing animation.
Clamp Load - The compressive load induced in the joint by the installed fastener. The residual clamp load (or joint pre-tension) is the compressive load remaining in the joint after the fastener is installed. Higher clamp loads are experienced during fastener installation (pulling force).
Clench - The ability of a fastener to draw together and hold together initially separated joint material components, during the installation process. i.e. "Gap closing" ability.
Collar Cropper/Splitter - An installation tool attachment that removes collars from lockbolt fasteners.
Complete Hole Fill - Fasteners with this capability expand to fill irregular, slotted, oversize or misaligned holes.
Drive Screw - The male threaded part in the nose of a threaded insert installation tool, which engages the female thread of inserts.
Fastener Body - The section of the fastener, excluding the head, which is generally the functioning/expanding part in contact with the joint.
Fatigue Strength - The ability of a fastener to resist fracture when subjected to cyclic variations in stress.
Fillet Radius - The concave junction at two intersecting surfaces of a fastener.
Fit - The range of tightness within a joint, which can occur due to the combination of fastener and parent material tolerances.
Flange - A disc shaped rim formed on the end of a cylindrical object, often related to the head geometry of a fastener.
Flanged Collar - A type of lockbolt collar with a flange, which provides an increased bearing surface.
Full Collar - A standard full height lockbolt collar.
Gap Closing - See 'Clench'
Grip - The total thickness of a closed joint.
Grip Range - The difference between the minimum and maximum grip at which a fastener will operate.
Half Collar - A reduced height lockbolt collar used for minimal collar protrusion. Note: will reduce tensile performance.
Headform - The style characteristics of the fastener head. Eg. low profile, large flange, countersunk.
Hole Fill - The ability of a fastener to fill the clearance hole in which it is installed. It is achieved by radial expansion of the fastener body during the installation process.
Host Material - See 'Joint Material'
Hydro-Pneumatic - Refers to installation tools. The use of an air over oil intensification system to generate the necessary forces required for fastener installation.
Installation Tool - The tooling used to install a fastener. Can be hand operated or powered.
Joint Material - The application material which is being fastened together. Also referred to as the parent material.
Lead-in Chamfer - The tapered end of a fastener which aids insertion into the hole.
Lockbolt Fastener - A two piece fastener comprising of a pin and collar, e.g. Avdelok® or Maxlok®. Access is required to both sides of the joint and installation is achieved by swaging the collar onto the locking grooves of the pin.
Locking Grooves - A set of grooves on the pin of a lockbolt fastener, into which the collar is swaged.
Magazine-Fed - (with reference to Avdel® Speed Fastening System) Refers to a number of speed fasteners, which may be handled and loaded into an installation tool as a single item.
Mandrel - (with reference to Avdel® Speed Fastening System) A specially processed steel rod onto which the magazine of speed fasteners is loaded. The stem of a breakstem fastener can also be referred to as a mandrel.
Maximum Grip - The largest recommended thickness of joint material for a fastener.
Maximum Torque - The maximum recommended torque to be applied to the bolt, which will not cause thread distortion or failure in the threaded insert.
Mechanically Locked Stem - The stem or mandrel is locked in the fastener shell during placement via a mechanical system. This eliminates the risk of the stem vibrating loose from the fastener head and the problems associated with loose stems e.g. Monobolt®. Please view fastener placing animation
Minimum Grip - The smallest recommended thickness of joint material for a fastener.
Nose Assembly/Nose Equipment - A kit of parts fitted to an installation tool. The nose assembly must be matched to a specific fastener as it influences its installation and performance.
Nose Tip - The interchangeable front most part of a nose assembly. The nose tip must be matched to a specific fastener as it influences its installation and performance.
Parent Material - See 'Joint Material'
Passivation/Passivated - A process which enhances the appearance and corrosion resistance of certain plated finishes on fasteners.
Peel-type Tail - A rivet body which is designed to split open on the blind side of the joint during the installation process to provide a large blind side bearing area in soft materials e.g. T-Lok®. Please view fastener placing animation.
Pod - (with reference to Avdel® Speed Fastening System) A magazine of speed fasteners contained within a strip of bonded paper tape.
Pull Grooves - A set of grooves on a fastener stem to enhance the grip of the tool when pulling.
Pull-Out - The minimum force required to cause the insert to pull through and out of the parent material.
Pulling Force - The axial force the tool applies during the installation of fasteners.
Push-Out - The minimum force required to cause the insert to push through and out of the parent material.
Repetition Riveting - Refers to the Avdel® Speed Fastening System.
Residual Clamp Load - See 'Clamp Load'
Shank Length - A dimensioned length from the fastener head to the tail.
Shear Load - The load applied to a fastener along the joint interface.
Sheet Take-up - See 'Clench'
Speed Fastener - A tubular fastener which is specifically configured as part of the Avdel® speed fastening system. The fasteners are supplied as multiples in a disposable magazine, or loose for Avdel® continuous feed systems.
Speed Fastening System - (with reference to Avdel® Speed Fastening System) A speed fastening installation tool into which a magazine of fasteners is loaded. This system facilitates very rapid installation rates.
Splines - Raised ridges around the fastener body to facilitate continuity between the fastener and joint material.
Stem - The component part of a breakstem fastener that is retained within the body. Also known as the mandrel.
Stem Retention - The force required to separate the stem from the body of an uninstalled breakstem fastener.
Swaging - The action of permanently radially deforming the collar of a lockbolt onto the pin.
Tensile Load - The load applied to a fastener along its length.
Threaded Insert - An insert for installation into sheet material where a receptacle for a male threaded component is required. Please view installation animation of blind threaded inserts.
Through Hardened - A process to increase uniform material hardness.
TIR Approved - A standard used by the Vehicle Inspectorate - Executive Agency. It is an approved bonding scheme enabling goods vehicles to travel between countries approved by their respective Customs Authorities. The bonding scheme ensures that all load compartments, once sealed (using TIR approved fasteners), cannot have anything added or taken from them without breaking seals or leaving obvious traces of structural damage.
Torque-To-Turn - Typically the torque required to rotate the installed fastener in the application material, usually applies to threaded inserts.
Ultimate Shear Strength - The failure load of the fastener in a shear situation. It may not reflect the strength of the joint material.
Ultimate Tensile Strength - The failure load of the fastener in a tensile situation. It may not reflect the strength of the joint material.
UNC - Unified Coarse Thread - An imperial thread form standard, prefered in the USA. It is covered by British Standard BS 1580.
UNF - Unified Fine Thread - An imperial thread form standard, prefered in the USA. It is covered by British Standard BS 1580.