left hand thread - tradução para Inglês
![BA]] standards are discussed. The SAE series was not mentioned—at the time this edition of the ''Handbook'' was being compiled, they were either still in development or just newly introduced.](https://commons.wikimedia.org/wiki/Special:FilePath/American Machinists Handbook--2e--p21--v001.png?width=200 "BA]] standards are discussed. The SAE series was not mentioned—at the time this edition of the ''Handbook'' was being compiled, they were either still in development or just newly introduced.")
![The basic profile of all [[UTS thread]]s is the same as that of all [[ISO metric screw thread]]s. Only the commonly used values for ''D''<sub>maj</sub> and ''P'' differ between the two standards.](https://commons.wikimedia.org/wiki/Special:FilePath/ISO and UTS Thread Dimensions.svg?width=200 "The basic profile of all [[UTS thread]]s is the same as that of all [[ISO metric screw thread]]s. Only the commonly used values for ''D''<sub>maj</sub> and ''P'' differ between the two standards.")
![SAE]] standards (including screw size standards), reported in the journal ''Horseless Age'', 1916](https://commons.wikimedia.org/wiki/Special:FilePath/Survey results on use of SAE standards Horseless Age v37 n9 1916-05-01 p353.png?width=200 "SAE]] standards (including screw size standards), reported in the journal ''Horseless Age'', 1916")
left:40px">общая лексика
left:60px">левая резьба
left:40px">медицина
left:60px">шаг резьбы
left:40px">нефтегазовая промышленность
left:60px">шаг резьбы (в замке или на муфте)
Definição
Wikipédia
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 through friction and slight elastic deformation.
