fastener banner 3A fastener, abbreviated as FSTNR, is a type of hardware component used to mechanically join two or more objects together.  Fasteners are typically used to create a non-permanent joint that can be easily disassembled or reassembled, such as in the case of screws, bolts, nuts, rivets, and clips.  Fasteners come in many different shapes, sizes, and materials, and are designed to meet specific requirements of different applications.  For example, some fasteners are designed to be resistant to corrosion or high temperatures, while others are designed to provide a secure and tamper-resistant connection.  Fasteners are used in a wide variety of industries and applications, including construction, automotive, aerospace, and electronics.  They play a critical role in ensuring the safety and reliability of structures and products, and are often subjected to rigorous testing and standards to ensure their performance and durability.

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fastener Index


fastener Design Classification

  • Permanent  -  These fasteners are single use, intended to join two materials and can’t be removed once installed.
    • Nail
      • Box Nail
      • Bright Nail
      • Casing Nail
      • Coated Nail
      • Common Nail
      • Duplex Nail
      • Drywall Nail
      • Finish Nail
      • Galvanized Nail
        • Electrogalvanized Nail
        • Hot-dip Galvanized Nail
        • Mechanical Galvanized Nail
      • Head Nail
      • Helix Nail
      • Length Nail
      • Phosphate-coated Nail
      • Point Nail
      • Ring Shank Nail
      • Shank Nail
      • Sinker Nail
      • Spike Nail
    • Rivet
      • Blind Rivet
      • Conical Head Rivet
      • Countersunk Rivet
      • Drive-pin Rivet
      • Flathead Rivet
      • Flush Rivet
      • Friction-lock Rivet
      • Mushroom Head Rivet
      • Pan Head with Tapered Neck Rivet
      • Self-piercing Rivet
      • Solid Rivet
      • Snap Head Rivet
      • Split Rivet
      • Tubular Rivet
    • Weld
  • Removable  -  These fasteners are designed specifically to join two materials or objects, with the option to be removed and reused without damaging the objects they hold together.
    • Bolt
      • Carriage Bolt, Fin Neck
      • Carriage Bolt, Ribbed Neck
      • Carriage Bolt, Short Neck
      • Timber Bolt
      • Elevator Bolt
      • Wire Eye Bolt
      • Forged Eye Bolt
      • Forged Machinery Eye Bolt
      • Forged Eye Bolt with Shoulder
      • Forged Machinery Eye Bolt with Shoulder
      • Wire Eye Lag
      • Hanger Bolt
      • Hex Heavy Bolt
      • Hex Bolt Full thread tap bolt
      • Lag Bolt
      • Shoulder Bolt Socket drive
      • Square Bolt
      • J-Bolt Round bend
      • U-Bolt Round bend
      • U-Bolt Square bend
    • Nut
      • T-Nut
      • Two-way Reversible Lock Nut
        • Wing Nut
      • Square Nut
      • Square Heavy Nut
      • Square Machine Screw Nut
      • Hex Slotted Castle Nut
      • Hex Slotted Heavy Nut
      • Hex High Crown Cap Nut
      • Hex Low Crown Cap Nut
      • Hex Finished Jam Nut
      • Hex Heavy Jam Nut
      • Hex Jam Nylon Lock Nut
      • Hex Lock Nut Nylon Insert
      • Hex K-Lock Nut
      • Prevailing Torque Lock Nut
      • Hex Machine Screw Nut
      • Hex Heavy Coupling Nut
      • Hex Finished Coupling Nut
      • Hex Flange Nut
      • Hex Finished Nut
      • Hex Heavy Nut
      • Hex Acorn Nut
      • Hex Cap Nut
    • Screw
      • Decking Screw
      • Double Ended Screw
      • Drywall Screw
      • Eye Bolt Screw
      • Framing Screw
      • Fillister Head Screw
      • Hammer Drive Screw
      • Hex Cap Screw
      • Lag Screw
      • Machine Screw
      • Masonary Screw
      • Oval Head Screw
      • Pan Head Screw
      • Particle Board Screw
      • Pocket Hole Screw
      • Security Screw
      • Selt Tapping Screw
      • Set Screw
      • Sheet Metal Screw
      • Shoulder Screw
      • Socket Head Screw
      • Tamper Proof Screw
      • Thread Cutting Machine Screw
      • Washer Faced Screw
      • Weld Screw
      • Wood Screw
    • Stud
      • Bonding Stud
      • Clinch Stud
      • Double-end Stud Bolt
      • Double-end Stud Bolt with Reduced Shank
      • Dowel Screw
      • Full Threaded Stud Bolt
      • Flange Stud Bolt
      • Tap End Stud Bolt
      • Welding Stud
    • Washer
      • Dock Washer
      • Fender Washer
      • Finishing Washer
      • Flat Washer
      • SAE Flat Washer
      • USS Flat Washer
      • Lock Washer
      • Lock Washer External Tooth
      • Lock Washer Internal Tooth
      • High Collar Lock Washer
      • Ogee Washer
      • Square Dock Washer
      • Spring Washer
      • Tapper Washer
      • Tooth Washer



  • FSTNR - Fastener
  • ANTP - American National Taper Pipe
  • ANPT - Aeronautical National Pipe Taper
  • ANS - American National Standard replaced with UNS
  • BA - British Association
  • BSF - British Standard Fine
  • BSP - British Standard Pipe
  • BSW - British Standard Whitworth
  • ISO - International Organization for Standardization
  • NPT - National Pipe Thread Tapered Thread
  • NPTF - National Pipe Taper Fuel - Dryseal
  • UNS - Unified National Standard
  • USS - United States Standard
  • UTS - Unified Thread Standard


fastener standards

ASME Standards

  • ASME B1.20.1 - Pipe Threads, General Purpose, Inch
  • ASME B1.20.3 - Dryseal Pipe Threads, Inch
  • ASME B18.12 - Glossary of Terms for Mechanical Fasteners
  • ASME B18.18 - Quality Assurance for Fasteners


Fastener Glossary


  • Active Coils  -  Coils that are free to move under load.
  • Aerotight Nut  -  A torque prevailing nut for all metal construction. The nut is slotted in two places which, after the nut has been tapped, are bent slightly inwards and downwards.  When the nut is screwed onto the bolt thread the two slotted parts are forced back to their original position.  Their stiffness causes the nut threads to bind onto the bolt threads and thus provides a prevailing torque. 
  • Allowance  -  The clearance is between internal or external threads.  Not all classes of threads have an allowances.  For metric threads the allowance is called the fundamental deviation.
  • Alloy Steel  -  A steel that one or more elements (other than carbon) have been added.
  • Anchor  -  Types of anchores.
  • Anchor Bolt  -  Anchor bolt is a threaded item used to secure an embed fastener into concrete, structural supports, walls, etc..
  • Angle Controlled Tightening  -  A tightening procedure in which a fastener is first tightened by a pre-selected torque (called the snug torque) so that the clamped surfaces are pulled together, and then is further tightened by giving the nut an additional measured rotation.
  • Anti-friction Coating  -  These coatings are dry lubricants consisting of suspensions of solid lubricants, such as graphite, PTFE or molydbenum disulphide of small particle size in a binder.
  • Anti-seize Compound  -  An anti-seize compound is used on the threads of fasteners in some applications.  The purpose of the compound depends upon the application.
  • Annealing  -  A process of heat treatment that changes the properties of metals.
  • Applied Force  -  Can come from different types of forces, one of them could be Newton's Second Law.
  • Autolock Nut  -  A torque prevailing nut.


  • Baking  -  Heating of electroplated springs to relieve hydrogen embrittlement.
  • Band Hanger  -  A pipe attachment providing vertical adjustment, normally of a formed steel strap.
  • Basic Thread Profile  -  This is the theoretical profile of external and internal threads with no manufacturing tolerance applied.
  • Beam Clamp  -  A clamp that is used to attach rod hangers to beams by clamping onto the beam flange.
  • Black Bolts and Nuts  -  The word black refers to the comparatively wider tolerances employed and not necessarily to the colour of the surface finish of the fastener.
  • Bolt  -  A fastener with a head and threaded on one end only.
  • Bolt Head  -  Formed by heating the end of a round piece of steel round bar then forged in to a head shape.
  • Bolt Grip Length  -  Total distance between the underside of the nut to the bearing face of the bolt head, includes washer and gasket thickness etc.
  • Bolt Identification Marking  -
  • Bolt Inch to Metric  -
  • Bolt Normal Length  -  The distance from the bottom of the bolt head to the end of the bolt.
  • Bolt Stud  -  A bolt stud is threaded on both ends or the full length.
  • Bolt Torque  -  Torque, also called moment of force, is a rotational moment. It is a measure of how much twisting is applied to tighten (turn) the nut on a bolt.
  • Bolt Wrench Size (in)  -
  • Bolt Wrench Size (mm)  -
  • British Sandard Fine  -  A thread form based upon the British Standard Whitworth form but with a finer thread (more threads per inch for a given diameter).  This thread form was first introduced in 1908, the thread form is specified in BS 84: 1956.
  • BSW  -  British Standard Whitworth
  • Buckling  -  Bowing or lateral displacement of a compression spring when compressed, related to slenderness ration L/D.
  • Bump Thread  -  It is a modified thread profile.  The thread form has a small projection at the pitch diameter that eliminates the clearance from the thread assembly on both flanks.  By doing this it is claimed that resistance to vibration loosening is significantly improved.


  • Center Beam Clamp  -  A jaw type beam clamp use with I-beams and wide flange beams which provides a centered beam connection.
  • Clevis Hanger  -  A fastener that provides vertical adjustment, consisting of a clevis type top bolted to a formed steel bottom strap.
  • Closed Ends  -  The ends of a compression springs with coil pitch angle reduced to touch the adjacent coil, can be one or more coils.
  • Closed and Ground Ends  -  Same as closed ends except the ends are ground to have a flat surface.
  • Close Wound  -  Adjacent coils are touching.
  • Cold Forming  -  A material is placed between two dies and compressed into a shape.
  • Compression Spring  -  A compression spring is a open-coil helical springs wound to resist the compression force along the wind axis.  The spring will always resist and pushing back the compression force to its origional length.
  • Compression Strength  -  Compression strength is the ability of a material to withstand applied loads without failure.
  • Corrosion Resistant  -  The ability to resist corrosin under certain conditions.
  • Cut Thread  -  A threading method produced by removing material from the surface with a form cutting tool.


  • Dacromet  -  A high performance surface coating that can be applied to fasteners.  The coating consists of zinc flakes that are oven heated onto the metal surface.
  • Decompression Point  -  The point at which there is zero pressure at the joint interface as a result of forces applied to the joint.
  • Deflection or Displacement  -  The motion of spring ends by adding or removal of an external load.
  • Deformation  -  Is measured by how much an object is deformed from its origional dimensions.
  • Direct Tension Indicator  -  Projections on the face of the washer that deform under pressure as the bolt is put under tension. An indication of the tension in the bolt can be made by measuring the gap between the washer face and the nut or bolt head. The smaller the gap - the greater the tension in the bolt.
  • Dynamic Friction  -  Resistance to relative movement of two bodies that are already in motion.


  • Effective Diameter  -  See pitch diameter
  • Elasticity  -  Measures the stiffness of an elastic material.
  • Elastic Modulus  -  The ratio of the stress applied to a body or substance to the resulting strain within the elastic limits.
  • Elastic Potential Energy  -  The energy stored in objects as the result of deformation, such as a spring when stretching or compressing.
  • Extension Hook  -  The hook is made from the end coil and bent at the center opening extended from the coil.
  • Extension Spring  -  A helical spring like a compression spring with hooks on each end.
  • External Thread  -  A screw thread that is formed on the external cylinder.  Also called male thread.


  • Fastener Length  -  Measured from the top of the head to the bottom of the threads.
  • Force  -  The push or pull of an object resulting in a change from rest or motion.
  • Forging  -  The process of forming raw steel by displacement under force into specified shapes.
  • Free Length  -  Overall length of a spring which is not under load.
  • Friction  -  The mechanical resistance to the relative movement of two surfaces.
  • Friction Coefficient  -  The ratio between two contacting surfaces and the frictional force that resists the normal force of the object.


  • Galling  -  A severe wear which occurs during the pressure of sliding contact, one surface relative to another.


  • Hex Head Bolt  - A bolt with six sided head.
  • Hex Head Cap Screw  -  A hex head screw with a flat and washer faced bearing surface under the head.
  • Hooke's Law  -  States that the amount of spring force, compressed or stretched, is proportional applied to the spring deformation.  The minus sign shows that the force is in the opposite direction of the force that is compressed of stretched.


  • IFI  -  Industrial Fasteners Institute
  • Initial Tension  -  A force that keep coils of an extension spring closed and must be overcome before the coils start to open.
  • Internal Thread  -  A screw thread that is formed inside a hole.  Also called female thread.




  • Leaf Spring Stiffness  -  Leaf springs are spring made of thin strips of metal (could be a single strip) stacked in layers to asorbe the vibration.  They are normally used on suspension systems for wheeled vehicles or trailers.
  • Left Hand Thread  -  A screw head that rotates counterclockwise direction.  Not as widely used as righthanded threads.
  • Load  -  The force applied to a spring that causes a deflection.
  • Lock Nut  -  Resists loosening under vibration and torque.


  • Major Diameter  -  The largest diameter of a screw thread.
  • Mean Coil Diameter  -  The outside diameter minus one wire diameter.
  • Minor Diameter  -  The smaller diameter of a screw thread.
  • Moment Arm  - The distance from the pivot point to the point where the force occurs.


  • Nail  -  Types of nails.
  • National Pipe Thread  -  NPT pipe threades or American Standard Taper Pipe Threads are used frequently in the oil and gas industry.
  • Nominal Diameter  -  The external size diameter designated of pipe or threads.
  • Number of Active Coils  -  Active coils are the open wound coils exerting energy while under a load of compression, extending, or deflection.
  • Nut  -  Types of nuts.
  • Nut Runner  -  A torque control fastener tightening tool that is usually powered by compressed air.



  • Pitch  -  Distance from center to center of wire in adjacent coils.
  • Pitch Diameter  -  See thread pitch diameter
  • Plain End  -  End coils of a compression spring having a constant pitch and ends not squared.
  • Preload  -  The tension created in a fastener when first tightened but reduces after a period of time.
  • Pressure  -  The force exerted perpendicular to the surface of an object and is expressed as force per unit area.
  • Proof Load  -  The amount of stress that the fastener can withstand without experiencing deformation.


  • Quenching  -  A process of quickly cooling an elevated temperature.


  • Right Hand Thread  -  A screw head that rotates clockwise.


  • Set  -  Permanent change in height, length, or position after a spring is stressed beyond material's elastic limit.
  • Shank Diameter  -  The smooth part of the bolt above the threads.
  • Shear Stress  -  Tends to deform the material by breaking rather than stretching without changing the volume by restraining the object.
  • Shot Peening  -  Blasting surfaces of spring material with steel or glass pellets to induce compressive stresses that improve fatigue life.
  • Side Hook  -  The hook is made from the end coil and bent at the side opening close to the coil.
  • Slenderness Ratio  -  The ratio of spring length to mean coil diameter.
  • Solid Height  -  Length of a compression spring when under sufficient load to bring all adjacent coils into contact.
  • Spiral Spring  -  Springs formed on a wound spiral plane from a flat strip or wire.
  • Spring  -  Springs are mechanical devices of flat wire or round wire that can store potential energy because of its elasticity in a spiral coil used to compress, extend, pull, or rotate using an applied force.
  • Spring Constant  -  The ratio of opposing force to the displacement from the origional position or how much force is needed to change a springs distance.
  • Spring Diameter  -  Distance from center of wire diameter to center of wire diameter.
  • Spring Displacement  -  Spring deflection or travel distance, is the compression (a repulsive force) or stretching (an attractive force) of a spring.
  • Spring Energy  -  A measure of the potential energy stored in elastic materials as the result of their stretching or compressing.
  • Spring Index  -  The ratio between the spring and wire diameter for a helical spring.
  • Spring Load  -  The load applied to a spring to compress the length.
  • Spring Mean Coil Diameter  -
  • Spring Number of Active Coils  -  Active coils are the open wound coils exerting energy while under a load of compression, extending, or deflection.  A coil is formed when it is wound one complete 360 degree helix starting with the second coil and count to the second coil on the other end.
  • Spring Pitch  -  The angle of the coils.
  • Spring Potential Energy  -  The stored energy as a result of the objects elastic deformation.
  • Spring Rate  -  The change in load per unit of deflection.
  • Stress Relief  -  A low temperature heat treatment given to springs to relieve residual stresses produced by prior cold forming.
  • Spring Solid Coil Height  -  The total compression of all coils.
  • Spring Stretch Length  -
  • Spring Tension  -  How much load/force is initially exerted on the spring to expand it.
  • Spring Travel Length  -
  • Spring Wire Diameter  -
  • Spring Wire length  -
  • Spring Wire Stress  -
  • Static Friction  -  The force that resists  relative movement and keeps objects at rest.
  • Static Friction Coefficient  -  The amount of force that resists motion that is on the verge of motion.
  • Strain  -  The deformation, stretched or compressed, of a material compared to its original length.
  • Stress  -  The force per unit area of cross-section.


  • Tap bolt  -  A bolt that is threaded to the botom of the head.
  • Temperature  -  The amount of heat or cold, but it is neither heat or cold.
  • Tensile Strength  -  The maximum stress a material can resist before it starts to elongate.
  • Tension Strength  -  The capacity of a material to resist a force tending to stretch it.
  • Thread Angle  -  The angle between the thread flanks.
  • Thread Axis  -  The imaginary distance equally between the major and minor diameters.
  • Thread Count  -  The number of threads per inch (TPI), used for US threads.
  • Thread Crest  -  The peak of a thread at the major diameter.
  • Thread Flank  -  The side of a thread between the major and minor diameters.
  • Thread Height  -  The perpendicular distance between the major and minor diameters.
  • Thread Length  -  Length of the cylinder that is threaded.
  • Thread pitch  -  The distance measured parallel between the crests of one thread to the next thread.
  • Thread Pitch Diameter  -  The imaginary diameter equal distance between the major and minor diameters.  Also called effective diameter.
  • Thread Root  -  The bottom of the thread.
  • Torque  -  A rotational moment.
  • Tortion Spring  -  Helical springs that store mechanical energy to exert a torque or rotary force.  Compression springs and extension springs work with pulling and pushing forces, but tortion springs work with twisting forces.
  • Total Number of Coils  -  The sum of the number of active and inactive coils in a spring body.


  • Ultimate Tensile Strength  -  The maximum stress a material can resist before it starts to elongate.
  • UNC  -  United National Course
  • UNEF  -  United National Extra Fine
  • UNF  -  United National Fine
  • UNR  -  United National (UN)



  • Wahl Correction Factor  -  A method to find out the effect of direct sheat and change in coil curvature in a spring.
  • Washer  -  Types of washers.



  • Yield Point  -  The point where an elastic material is permanent change in length with no extra load force.
  • Yield Strength  -  The minimum stress that leads to permanent deformation of the material.


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Angle Controlled Tightening
Anti-friction Coating
Anti-seize Compound

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