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Thread-locking Fluid
Thread-locking fluid or threadlocker is a single-component adhesive, applied to the threads of fasteners such as screws and bolts to prevent loosening, leakage, and corrosion. Most thread-locking formulas are methacrylate-based and rely on the electrochemical activity of a metal substrate to cause polymerization of the fluid. Thread-locking fluid is thixotropic, which allows it to flow well over time, yet still resist shocks and vibrations. It can be permanent or removable; in the latter case, it can be removed with heat, for example. Typically, brands are color-coded to indicate strength and whether they can be removed easily or if they require heat for removal. History Thread-locking fluid was developed by American professor Vernon K. Krieble in 1953. His company, American Sealants, founded the Loctite brand. An early version of the compound was patented in 1960. Properties Typically, thread-locking fluids are methacrylate-based, and cure anaerobically. Thread-lockin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loctite
Loctite is an American brand of adhesives, sealants, surface treatments, and other industrial chemicals that include acrylic, anaerobic, cyanoacrylate, epoxy, hot melt, silicone, urethane, and UV/light curing technologies. Loctite products are sold globally and are used in a variety of industrial and hobbyist applications. History In 1953, American Schwenkfelder professor Vernon K. Krieble developed anaerobic threadlocking adhesives in his basement laboratory at Trinity College in Hartford, Connecticut. Krieble’s company, American Sealants, founded the Loctite brand, which was promoted as ushering in a new era of mechanical reliability by eliminating the vibrational loosening of mechanical fasteners, a frequent cause of machine failure. In 1956, the name Loctite was chosen by Krieble’s daughter-in-law, Nancy Brayton Krieble. The Loctite sealant made its official public debut at a press conference at the University Club of New York on July 26 of that year. In 1963, Amer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glue Stick
Glue sticks are solid and hard adhesives in twist or push-up tubes. Users can apply glue by holding the open tube to keep their fingers clean and rubbing the exposed stick against a surface. Applications Most glue sticks are designed to glue paper and card stock together, and are not as strong as some liquid-based variants. They can be used for craft and design, office use and at school. There are several varieties: permanent, washable, acid-free, non-toxic, solvent-free, and dyed (e.g. to see where the glue is being applied). Brands In 1969, the German company Henkel invented the glue stick after studying the "twist-up ease" and convenience of lipstick applicators. The product was released under the Pritt Stick brand. By 1971 the Pritt Stick was being sold in 38 countries, by 2001 in 121. The first solvent-free, multipurpose glue stick that could be used for other materials (e.g. wood, glass and some plastics) was the "PowerPritt", which was put on the market in 2003. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acrylate Polymers
An acrylate polymer (also known as acrylic or polyacrylate) is any of a group of polymers prepared from acrylate monomers. These plastics are noted for their transparency, resistance to breakage, and elasticity. Acrylate polymer is commonly used in cosmetics, such as nail polish, as an adhesive. History The first synthesis of acrylic polymer was reported by G.W.A Kahlbaum in 1880. Acrylic elastomers Acrylic elastomer is a general term for a type of synthetic rubber whose primary component is acrylic acid alkylester (ethyl or butyl ester). Acrylic elastomer possesses characteristics of heat and oil resistance, with the ability to withstand temperatures of 170–180 °C. It is used primarily for producing oil seals and packaging related to automobiles. Acrylic elastomer can generally be characterized as one of two types. "Old" types include ACM (copolymer of acrylic acid ester and 2-chloroethyl vinyl ether) containing chlorine and ANM (copolymer of acrylic acid ester and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesives
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing, mechanical fastenings, or welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, the cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by ''reactive'' or ''non-reactive'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bolted Joint
A bolted joint is one of the most common elements in construction and machine design. It consists of a male threaded fastener (e. g., a bolt) 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. Joint types In a tension joint, the bolt and clamped components of the joint are designed to transfer an applied tension load through the joint by way of the clamped components by the design of a proper balance of joint and bolt stiffness. The joint should be designed such that the clamp load is never overcome by the external tension forces acting to separate the joint. If the external tension forces overcome the clamp load (bolt preload) the clamped joint components will separate, allowing relative motion of the components. The second type of bolted joint transfers the applied load in shear of the bolt shank and relies on the shear strength of the bolt. Tension loads on such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Safety Wire
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. Safety wire is available in a variety of gauges and materials, depending on the application. In aircraft and racing applications, stainless steel wire is used, such as in diameter. Typically, the wire is threaded through a hole drilled into a fastener or part, then twisted and anchored to a second fastener or part, then twisted again. Application Principle There are a few techniques for different applications. The word ''safetying'' is universally used in the aircraft industry. Briefly, safetying is defined as: "Securing by various means any nut, bolt, turnbuckle etc., on the aircraft so that vibration will not cause it to loosen during operation." These practices are not a means of obtaining or maintaining torque, rather a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jam Nut
A jam nut is a low profile type of nut, typically half as tall as a standard nut. It is commonly used as a type of locknut, where it is "jammed" up against a standard nut to lock the two in place. It is also used in situations where a standard nut would not fit. The term "jam nut" can also refer to any nut that is used in the same function (even a standard nut used for the jamming purpose). Jam nuts, other types of locknuts, lock washers, and thread-locking fluid are ways to prevent vibration from loosening a bolted joint. Use of two nuts to prevent self-loosening In normal use, a nut-and-bolt joint holds together because the bolt is under a constant tensile stress called the ''preload''. The preload pulls the nut threads against the bolt threads, and the nut face against the bearing surface, with a constant force, so that the nut cannot rotate without overcoming the friction between these surfaces. If the joint is subjected to vibration, however, the preload increases and decre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locknut
A locknut, also known as a lock nut, locking nut, self-locking nut, prevailing torque nut,. stiff nut or elastic stop nut, is a nut that resists loosening under vibrations and torque. Prevailing torque nuts have some portion of the nut that deforms elastically to provide a locking action. Free-spinning locknuts exist which carry the advantage of not requiring extra torque until seated. Types There are various kinds of specialised lock nuts, including: * Castellated nut * Distorted thread locknut ** Centerlock nut **Elliptical offset locknut ** Toplock nut **Philidas nut * Interfering thread nut ** Tapered thread nut * Jam nut * Jet nut (K-nut). * Keps nut (K-nut or washer nut) with a free-spinning washer. In the locknut form, this is a star-type lock washer. * Plate nut * Polymer insert nut (Nyloc nut) * Security locknut All steel reusable nut for high vibration and harsh environments. * Serrated face nut * Serrated flange nut * Speed nut (sheet metal nut or Tinnerman nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lock Washer
A washer is a thin plate (typically disk-shaped, but sometimes square) with a hole (typically in the middle) that is normally used to distribute the load of a threaded fastener, such as a bolt or nut. Other uses are as a spacer, spring (Belleville washer, wave washer), wear pad, preload indicating device, locking device, and to reduce vibration ( rubber washer). Washers are usually metal or plastic. High-quality bolted joints require hardened steel washers to prevent the loss of pre-load due to brinelling after the torque is applied. Washers are also important for preventing galvanic corrosion, particularly by insulating steel screws from aluminium surfaces. They may also be used in rotating applications, as a bearing. A ''thrust washer'' is used when a rolling element bearing is not needed either from a cost-performance perspective or due to space restraints. Coatings can be used to reduce wear and friction, either by hardening the surface or by providing a solid lubricant (i.e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidised
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogenation, C=C (and other) bonds ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yield Strength
In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. In some materials, such as aluminium, there is a gradual onset of non-linear behavior, making the precise yield point difficult to determine. In such a case, the offset yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pound-foot (torque)
A pound-foot (lbf⋅ft) is a unit of torque representing one pound of force acting at a perpendicular distance of one foot from a pivot point. Conversely one pound-foot is the moment about an axis that applies one pound-force at a radius of one foot. The value in SI units is given by multiplying the following exact factors: :One pound (mass) = :Standard gravity = 9.80665 m/s2 :One foot = 0.3048 m This gives the exact conversion factor: :One pound-foot = newton metres. The name "pound-foot", intended to minimize confusion with the foot-pound as a unit of work, was apparently first proposed by British physicist Arthur Mason Worthington. Despite this, in practice torque units are commonly called the foot-pound (denoted as either lb-ft or ft-lb) or the inch-pound (denoted as in-lb). In most US industrial settings, the torque ranges are given in ft-lb rather than lbf-ft. Practitioners depend on context and the hyphenated abbreviations to know that these refer to neither ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
