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ISO Metric Screw Thread
The ISO metric screw thread is the most commonly used type of general-purpose screw thread worldwide. They were one of the first international standards agreed when the International Organization for Standardization (ISO) was set up in 1947. The "M" designation for metric screws indicates the nominal outer diameter of the screw thread, in millimetres. This is also referred to as the "major" diameter in the information below. It indicates the diameter of smooth-walled hole that an externally threaded component (e.g. on a bolt) will pass through easily to connect to an internally threaded component (e.g. a nut) on the other side. For example, an M6 screw has a nominal outer diameter of 6 millimetres and will therefore be a well-located, co-axial fit in a hole drilled to 6 mm diameter. Basic profile The design principles of ISO general-purpose metric screw threads ("M" series threads) are defined in international standard ISO 68-1. Each thread is characterized by it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screw Thread
A screw thread is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a ''straight'' thread and the latter called a ''tapered'' thread. A screw thread is the essential feature of the screw as a simple machine and also as a threaded fastener. The mechanical advantage of a screw thread depends on its ''lead'', which is the linear distance the screw travels in one revolution. In most applications, the lead of a screw thread is chosen so that friction is sufficient to prevent linear motion being converted to rotary, that is so the screw does not slip even when linear force is applied, as long as no external rotational force is present. This characteristic is essential to the vast majority of its uses. The tightening of a fastener's screw thread is comparable to driving a wedge into a gap until it sticks fast through friction and slight ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Standard Cycle
British Standard Cycle (BSC or BSCy or CEI) is a British Imperial screw thread standard. Unlike other major British imperial thread standards (British Standard Whitworth and British Standard Fine) the thread runs at a 60 degrees rather than a 55 degrees angle. All sizes inch and larger use 26 threads per inch (tpi), making them similar to 1 mm ISO threads, which are 25.4 per inch and also run at a 60 degrees angle. It was originally used with both bicycles and motorcycles. However it is now believed to be obsolete in motorcycle manufacture. In the bicycle industry it is still found on virtually all bottom bracket threads and the wheel axles of low-end models manufactured in China, which are derived from pre-WWII British roadsters. BS 811: 1950 provides specifications for British standard cycle threads. Cycle thread in and inch sizes also come in 20 tpi and 24 tpi options. 1/4" diameter cycle thread nuts and bolts have the same 26tpi as 1/4" BSF, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Association Screw Threads
British Association screw threads, or BA screw threads, are a set of small screw threads, the largest being 0BA at 6 mm diameter. They were, and to some extent still are, used for miniature instruments and modelling. They are unusual in that they were probably the most "scientific" design of screw, starting with 0BA at 6.0 mm diameter and 1.0 mm pitch and progressing in a geometric sequence where each larger number was 0.9 times the pitch of the last size. They then rounded to 2 significant figures in metric and then converting to inches and rounding to the thousandth of an inch. This anticipated worldwide metrication by about a century. The design was first proposed by the British Association in 1884 with a thread angle and depth based on the Swiss Thury thread, it was adopted by the Association in 1903. The Thury thread was different in that it went both positive and negative all the way up to a size of −20 which was 75.2 mm diameter by 8.23 mm pitch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASTM F568M
ASTM F568M is an ASTM International standard for metric bolts, screws and studs that are used in general engineering applications. It is titled: ''Standard Specification for Carbon and Alloy Steel Externally Threaded Metric Fasteners''. It defines mechanical properties for fasteners that range from M1.6 to 100 in diameter. The standard was withdrawn in 2012.. and has been replaced by ISO 898-1. This standard defines ''property classes'', the metric equivalent of a screw ''grade'', that are almost identical to those defined by ISO 898-1, except for the addition of the 8.8.3 and 10.9.3 classes. These two additional standards are fasteners that have the same mechanical properties as their base property class (i.e. 8.8 and 10.9), but are made from weathering steel. The standard is referenced by ASME B18.29.2M, which defines insert length selection for helical coil screw thread inserts. This is a standard set by the standards organization ASTM International, a voluntary standards deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASTM A325
ASTM A325 is an ASTM International standard for heavy hex structural Bolt (fastener), bolts, titled ''Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength''. It defines mechanical properties for bolts that range from in diameter. The equivalent metric standard is ASTM A325M, which is titled ''Standard Specification for Structural Bolts, Steel, Heat Treated 830 MPa Minimum Tensile Strength''. It defines mechanical properties for sizes M12–36.. This is a standard set by the standards organization ASTM International, a voluntary standards development organizations that sets technical standards for materials, products, systems, and services. In 2016, ASTM officially withdrew specification A325 and replaced it with ASTM F3125. To minimize confusion, bolt head markings are unchanged and the designation A325 is retained as a grade name within the new standard. In 1951, A325 bolts were recognized as equivalent to a hot driven ASTM A141 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japanese Industrial Standards
are the standardization, standards used for industrial activities in Japan, coordinated by the Japanese Industrial Standards Committee (JISC) and published by the Japanese Standards Association (JSA). The JISC is composed of many nationwide committees and plays a vital role in standardizing activities across Japan. History In the Meiji (era), Meiji era, private enterprises were responsible for making standards, although the Japanese government too had standards and specification documents for procurement purposes for certain articles, such as munitions. These were summarized to form an official standard, the Japanese Engineering Standard, in 1921. During World War II, simplified standards were established to increase matériel output. The present Japanese Standards Association was established in 1946, a year after Japan's defeat in World War II. The Japanese Industrial Standards Committee regulations were promulgated in 1946, and new standards were formed. The Industrial Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tolerances
Engineering tolerance is the permissible limit or limits of variation in: # a physical dimension; # a measured value or physical property of a material, manufactured object, system, or service; # other measured values (such as temperature, humidity, etc.); # in engineering and safety, a physical distance or space (tolerance), as in a truck (lorry), train or boat under a bridge as well as a train in a tunnel (see structure gauge and loading gauge); # in mechanical engineering, the space between a bolt and a nut or a hole, etc. Dimensions, properties, or conditions may have some variation without significantly affecting functioning of systems, machines, structures, etc. A variation beyond the tolerance (for example, a temperature that is too hot or too cold) is said to be noncompliant, rejected, or exceeding the tolerance. Considerations when setting tolerances A primary concern is to determine how wide the tolerances may be without affecting other factors or the outcome of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grub Screw
In American English, a set screw is a screw that is used to secure an object, by pressure and/or friction, within or against another object, such as fixing a pulley or gear to a shaft. A set screw is normally used without a nut (which distinguishes it from a bolt), being screwed instead in a threaded hole drilled in only one of the two objects to be secured. A set screw is often headless and threaded along its entire length, so that it will sit entirely inside that hole; in which case it may be called a grub screw or blind screw. Once fully and firmly screwed into the first object, the projecting tip of the set screw presses hard against the second object, acting like a clamp. The second object may have a machined detent (recess) to ensure that it cannot slide under the tip of the screw. On a shaft, this may be simply a flattened area. A set screw may have any type of drive, such as hex or square head, slot, or recessed --- cross (Phillips), hex (Allen), star (Torx), or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Button Head Screw
A button is a fastener that joins two pieces of fabric together by slipping through a loop or by sliding through a buttonhole. In modern clothing and fashion design, buttons are commonly made of plastic but also may be made of metal, wood, or seashell. Buttons can also be used on containers such as wallets and bags. Buttons may be sewn onto garments and similar items exclusively for purposes of ornamentation. In the applied arts and craft, a button can be an example of folk art, studio craft, or even a miniature work of art. In archaeology, a button can be a significant artifact. History Buttons and button-like objects used as ornaments or seals rather than fasteners have been discovered in the Indus Valley civilization during its Kot Diji phase (c. 2800–2600 BC). Buttons as apparel have been found at sites of the Catacomb culture, Russia (2500-1950 BC), at the Tomb of the Eagles, Scotland (2200–1800 BC), and at Bronze Age sites in China (c. 2000–1500 BC) and Ancient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Socket Head Cap Screw
Socket may refer to: Mechanics * Socket wrench, a type of wrench that uses separate, removable sockets to fit different sizes of nuts and bolts * Socket head screw, a screw (or bolt) with a cylindrical head containing a socket into which the hexagonal ends of an Allen wrench will fit * Socket termination, a termination used at the ends of wire rope * Socket, the receptacle into which a tapered tool is inserted * Socket, an opening in any fitting that matches the outside diameter of a pipe or tube Biology * Eye socket, a region in the skull where the eyes are positioned * Tooth socket, a cavity containing a tooth, in those bones that bear teeth * Dry socket, an opening as a result of the blood not clotting after a tooth is pulled * Ball and socket joint Computing * Network socket, an end-point in a communication across a network or the Internet * Unix domain socket, an end-point in local inter-process communication * socket(), a system call defined by the Berkeley sockets API * CP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hex Cap Screw-no Markings
Hex usually refers to: * A curse or supposed real and potentially supernaturally realized malicious wish * Hexadecimal, a base-16 number system often used in computer nomenclature Hex, HEX, or The Hex may also refer to: Magic * Hex sign, a barn decoration originating in Pennsylvania Dutch regions of the United States * Hex work, a Pennsylvania Dutch (German) folk magic system also known as pow-wow Engineering and technology * Hex key, a tool also known as a hex wrench or Allen wrench, used to drive fasteners * Hex key, a number sign (#) key on telephones (regional term used in Singapore and Malaysia) * High-energy X-rays, sometimes abbreviated "HEX-rays" * Hexcentric, an item of climbing protection equipment * Heat exchanger, a device for heat transfer * Hypersonic Flight Experiment, a planned mission of the Indian Space Research Organisation * Intel HEX, a computer file format * Uranium hexafluoride, a compound used in nuclear fuel refinement * Hex color, a six-digit, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
