A well nut is a blind rivet-like type of fastener used to blindly fasten a piece (much like a molly bolt) and to seal the bolt hole.
They are often referred to by the proprietary name Rawlnut or Rawl nut, the name by which they are known in the UK.[ citation needed ]
A well nut consists of a flanged neoprene bushing with a nut embedded in the non-flanged end. The bolt is passed through one of the pieces to be fastened and threaded onto the nut from the flanged end. The non-flanged end is then inserted through the other piece to be fastened. As the bolt is tightened, friction from the neoprene flange against the piece being fastened prevents the nut from turning. The bushing is compressed by the nut, forming a lip behind the piece being fastened, which compresses the fastened piece and seals the bolt hole. It can also be used in a solid workpiece. As the bolt draws the embedded nut towards it, the walls of the well exert a force on the hole walls, anchoring it. [1]
Well nuts are not particularly strong, but are useful for sealing holes and/or isolating vibrations. [2]
The well nut was originally developed by the United Shoe Machinery Corporation (USMC). [1]
A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. It is a deformable material that is used to create a static seal and maintain that seal under various operating conditions in a mechanical assembly.
A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is called the tail. On installation, the deformed end is called the shop head or buck-tail.
A fastener or fastening is a hardware device that mechanically joins or affixes two or more objects together. In general, fasteners are used to create non-permanent joints; that is, joints that can be removed or dismantled without damaging the joining components. Steel fasteners are usually made of stainless steel, carbon steel, or alloy steel.
A bolted joint is one of the most common elements in construction and machine design. It consists of a male threaded fastener that captures and joins other parts, secured with a matching female screw thread. There are two main types of bolted joint designs: tension joints and shear joints.
A socket wrench is a type of spanner that uses a closed socket format, rather than a typical open wrench/spanner to turn a fastener, typically in the form of a nut or bolt.
A safety wire or locking-wire is a type of positive locking device that prevents fasteners from falling out due to vibration and other forces. The presence of safety wiring may also serve to indicate that the fasteners have been properly tightened.
A sex bolt is a type of fastener comprising a mated pair of screw and post, which are a machine screw and a nut that is barrel-shaped. The nut has a flange and a protruding boss that is internally threaded. The bolt sits within the components being fastened, and the flange provides the bearing surface.
A fitting or adapter is used in pipe systems to connect sections of pipe or tube, adapt to different sizes or shapes, and for other purposes such as regulating fluid flow. These fittings are used in plumbing to manipulate the conveyance of fluids such as water for potatory, irrigational, sanitary, and refrigerative purposes, gas, petroleum, liquid waste, or any other liquid or gaseous substances required in domestic or commercial environments, within a system of pipes or tubes, connected by various methods, as dictated by the material of which these are made, the material being conveyed, and the particular environmental context in which they will be used, such as soldering, mortaring, caulking, plastic welding, welding, friction fittings, threaded fittings, and compression fittings.
A nyloc nut, also referred to as a nylon-insert lock nut, polymer-insert lock nut, or elastic stop nut, is a kind of locknut with a nylon collar that increases friction on the screw thread.
A flange nut is a nut that has a wide flange at one end that acts as an integrated washer. This serves to distribute the pressure of the nut over the part being secured, reducing the chance of damage to the part and making it less likely to loosen as a result of an uneven fastening surface. These nuts are mostly hexagonal in shape and are made up of hardened steel and often coated with zinc.
A T-nut, T nut, or tee nut is a type of nut used to fasten a wood, particle or composite materials workpiece, leaving a flush surface.
A distorted thread locknut, is a type of locknut that uses a deformed section of thread to keep the nut from loosening due to vibrations, or rotation of the clamped item. There are four types: elliptical offset nuts, centerlock nuts, toplock nuts and partially depitched (Philidas) nuts.
A rivet nut, also known as a blind rivet nut, or rivnut, is a one-piece internally threaded and counterbored tubular rivet that can be anchored entirely from one side. It is a kind of threaded insert. There are two types: one is designed to form a bulge on the back side of the panel as a screw is tightened in its threads. The other is similarly drawn in using a screw, but is drawn into the sleeve instead of creating a bulge.
A barrel nut is a specialized forged nut, and is commonly used in aerospace and ready-to-assemble furniture applications.
A jet nut, also known as a k-nut, is a special type of hex locknut that is commonly used in the aerospace and automotive racing industries.
A swage nut or self-clinching nut is a type of nut or threaded insert that is used on sheet metal.
A screw is an externally helical threaded fastener capable of being tightened or released by a twisting force (torque) to the head. The most common uses of screws are to hold objects together and there are many forms for a variety of materials. Screws might be inserted into holes in assembled parts or a screw may form its own thread. The difference between a screw and a bolt is that the latter is designed to be tightened or released by torquing a nut.
A nut is a type of fastener with a threaded hole. Nuts are almost always used in conjunction with a mating bolt to fasten multiple parts together. The two partners are kept together by a combination of their threads' friction, a slight stretching of the bolt, and compression of the parts to be held together.
A bolt is an externally helical threaded fastener capable of being tightened or released by a twisting force (torque) to a matching nut. The bolt has an external male thread requiring a matching nut with a pre-formed female thread.
A square nut is a four-sided nut. Compared to standard hexagonal nuts, square nuts have a greater surface area in contact with the part being fastened, and therefore provide greater resistance to loosening. They are also much less likely to become rounded-off after repeated loosening/tightening cycles. Square nuts are typically mated with square-headed bolts. Square nuts are used along with flat washers to avoid damage from its sharp edges and increase the strength of the fastener. Square nuts can have standard, fine or coarse threading with platings of zinc yellow, plain, zinc clear, tin and cadmium, among others. Most can meet either the ASTM A194, ASTM A563, or ASTM F594 standard.