{{short description|Angle between flanks of a screw thread}} thumb|right|300px|Diagram of a thread angle
In mechanical engineering, the '''thread angle''' of a screw is the included angle between the thread flanks, measured in a plane containing the thread axis.<ref name="Bhandari2007p203">{{Harvnb|Bhandari|2007|p=203}}.</ref> This is a defining factor for the shape of a screw thread. Standard values include: {{clear}}
{| class="wikitable" border="1" ! Name ! Code ! Angle ! Profile ! Standards |- | Most V-threads | M | 60° | 120px | including DIN 13 / ISO, NPT and UTS |- | Whitworth threads | W | 55°<ref>[https://journeymans-workshop.uk/whitworth.php BS 84: 1956]</ref> | 120px | DIN 49301 / BS |- | British standard pipe thread | G | 55° | 120px | DIN / BS / EN / ISO 228-1 / ISO 7-1 |- | National Pipe Thread | NPT | 60° | 120px | ASME B1.20.-1983 Pipe Threads, General Purpose, Inch |- | {{plainlist| * Knuckle thread<ref>[http://www.gewinde-normen.de/en/knuckle-thread-din-405.html Knuckle Thread DIN 405]</ref><ref>[http://www.gewinde-normen.de/en/knuckle-thread-din-20400.html Knuckle Thread DIN 20400]</ref><ref>[http://www.bornemann-gewindetechnik.de/en/products/threading-technology/knuckle-threads.html Bornemann]</ref> * Round thread }} | Rd | 30° | 120px<ref>[http://www.bornemann-gewindetechnik.de/dateien/pdf/en/Rundgewinde_2_ZG.PDF Knuckle thread]</ref> | DIN 405 / DIN 20400 |- | Acme thread<ref name="Bhandari2007p204">{{Harvnb|Bhandari|2007|p=204}}.</ref> | | 29° | 120px | ASME/ANSI B1.5-1988{{sfnp|Machinery's Handbook|1996|pp=1716}} |- | Metric trapezoidal threads<ref name="Bhandari2007p203"/> | Tr | 30° | 120px | DIN 103 |- | Buttress threads<ref name="Bhandari2007p204"/> | S | 45° | 120px | DIN 2781 |- | German buttress threads<ref name="Bhandari2007p204"/> | S | 30° | 120px | DIN 513 |- | Square threads<ref name="Bhandari2007p203"/> | Sq | 0° (parallel) | 120px | ? |- | Panzergewinde, "steel conduit thread" | Pg | 80° | 120px | DIN 40430 |- | British Association (BA) thread | BA | 47°{{nnbsp}}30'{{nbsp}}= {{#expr: 47 + 30/60}}° | 90px | BS 93:2008 |- | Löwenherz thread<ref>[http://www.gewinde-normen.de/en/loewenherz-thread.html Löwenherz thread]</ref> | | 53°{{nnbsp}}8'{{nbsp}}≈ {{#expr: 53 + 8/60 round 1}}° | | |- | Bodmer thread<ref>[http://www.gewinde-normen.de/en/bodmer-thread.html Bodmer thread]</ref> | | 50° | | |- | Thury thread<ref>Brooks, Randall C. "Standard Screw Threads for Scientific Instruments. Part 1: Production Techniques and the Filière Suisse." ''History and Technology,'' vol 5, 1988, pp. 68.</ref><ref>[https://www.gewinde-normen.de/en/thury-thread.html Thury thread]</ref> | | 47°{{nnbsp}}30'{{nbsp}}= {{#expr: 47 + 30/60}}° | | |}
==References== * List of DIN standards
===Notes=== {{reflist}}
===Bibliography=== *{{Citation | last = Bhandari | first = V B | title = Design of Machine Elements | publisher = Tata McGraw-Hill | year = 2007 | url = https://books.google.com/books?id=f5Eit2FZe_cC | isbn = 978-0-07-061141-2}}. * {{MachinerysHandbook25e}}
Category:Screws Category:Metalworking terminology Category:Threading (manufacturing)