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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 a male thread (e.g. on a bolt) will pass through easily to create a well-located connection to an internally threaded component (e.g. a nut) on the other side. That is, 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 its Screw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screw Thread
A screw thread, often shortened to 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grub Screw
Grub can refer to Grub (larva), of the beetle superfamily Scarabaeoidea, or as a slang term for food. It can also refer to: Places * Grub, Appenzell Ausserrhoden, Switzerland * Grub, St. Gallen, Switzerland * Grub (Amerang), a hamlet in Bavaria, Germany * Grub am Forst, a town in the district of Coburg in Bavaria, Germany * Grub, Thuringia, a municipality in the district of Hildburghausen in Thuringia, Germany Science and technology * Headless set screw, a British term * GNU GRUB, the GNU project's bootloader software * Grub (search engine), a distributed search crawler platform Other uses *The Grubs are Zurg's henchmen in ''Buzz Lightyear of Star Command'' * Grub Street Until the early 19th century, Grub Street was a street close to London's impoverished Moorfields district that ran from Fore Street east of St Giles-without-Cripplegate north to Chiswell Street. It was pierced along its length with narrow entr ..., the former name of a London street, which became a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garden Hose Thread
A garden hose, hosepipe, or simply hose is a flexible tube used to convey water. There are a number of common attachments available for the end of the hose, such as sprayers and sprinklers (which are used to concentrate water at one point or to spread it over a large area). Hoses are usually attached to a hose spigot or tap. Terminology The alternative term "hosepipe" is a chiefly British, South African, and southern US usage; "hose" or "garden hose" is the predominant term in other English-speaking areas. The term "hose" is also used for other types of flexible, water-carrying tubes such as fire hose used by fire departments. Description Garden hoses are typically made of extruded synthetic rubber or soft plastic, often reinforced with an internal web of fibers. As a result of these materials, garden hoses are flexible and their smooth exterior facilitates pulling them past trees, posts and other obstacles. Garden hoses are also generally tough enough to survive oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineering Tolerance
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 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buttress Thread
Buttress thread forms, also known as sawtooth thread forms or breech-lock thread forms. are screw thread profiles with an asymmetric shape, having one square face and the other slanted. They are most commonly used for leadscrews where the load is principally applied in one direction. The asymmetric thread form allows the thread to have low friction and withstand greater loads than other forms in one direction, but at the cost of higher friction and inferior load bearing in the opposite direction. They are typically easier to manufacture than square thread forms but offer higher load capacity than equivalently sized Trapezoidal thread forms. Buttress thread characteristics The buttress thread form is designed to handle axial thrust applied principally in one direction. The load-bearing thread face is perpendicular or at a slight slant (usually no greater than 7°) to the screw axis. The trailing face is slanted, often at 45°. The resulting thread form has the same low friction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Standard Whitworth
British Standard Whitworth (BSW) is an imperial-unit-based screw thread standard, devised and specified by Joseph Whitworth in 1841 and later adopted as a British Standard. It was the world's first national screw thread standard, and is the basis for many other standards, such as BSF, BSP, BSCon, and BSCopper. History The Whitworth thread was the world's first national screw thread standard, devised and specified by Joseph Whitworth in 1841. Until then, the only standardization was what little had been done by individual people and companies, with some companies' in-house standards spreading a bit within their industries. Whitworth's new standard specified a 55° thread angle and a thread depth of 0.640327''p'' and a radius of 0.137329''p'', where ''p'' is the pitch. The thread pitch increases with diameter in steps specified on a chart. The Whitworth thread system was later to be adopted as a British Standard to become British Standard Whitworth (BSW). An example of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Standard Pipe Thread
British Standard Pipe (BSP) is a set of technical standards for screw threads that has been adopted internationally for interconnecting and sealing pipes and fittings by mating an external (male) thread with an internal (female) thread. It has been adopted as standard in plumbing and pipe fitting, except in North America, where NPT and related threads are used. Types Two types of threads are distinguished: * Parallel (straight) threads, ''British Standard Pipe Parallel thread'' (''BSPP''; originally also known as ''British Standard Pipe Fitting thread''/''BSPF'' and ''British Standard Pipe Mechanical thread''/''BSPM''), which have a constant diameter; denoted by the letter ''G''. * Taper threads, ''British Standard Pipe Taper thread'' (''BSPT''), whose diameter increases or decreases along the length of the thread; denoted by the letter ''R''. These can be combined into two types of joints: ; Jointing threads: These are pipe threads where pressure-tightness is made through t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Standard Fine Thread
British Standard Fine (BSF) is a screw thread form, as a fine-pitch alternative to British Standard Whitworth (BSW) thread. It was used for steel bolts and nuts on and in much of Britain's machinery, including cars, prior to adoption of Unified, and later Metric, standards. For highly stressed conditions, especially in motorcycles, a finer thread, British Standard Cycle (BSC), was used as well. BSF was developed by R. E. B. Crompton, and his assistant George Field. BSF threads use the 55 degree Whitworth thread form. It was introduced by the British Engineering Standards Association in 1908.Sidders 1969, p.16 The table provides BSF sizes, the threads per inch A screw thread, often shortened to 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 ... and spanner jaw sizes. The BSC column indicates where BSF and BSC thread ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Standard Cycle
British Standard Cycle (BSC or BSCy) 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. Cycle thread in and inch sizes also come in 20 tpi and 24 tpi options. Traditionally the parts it would be found on are: * Front axle and seat pin clamp bolt diameter, 24 or 26 tpi threading * Rear axle diameter, 26 tp ... [...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 dev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASTM A325
ASTM A325 is an ASTM International standard for heavy hex structural 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 rivet. Types The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
