Engineering:Thread angle

From HandWiki
Short description: Angle between flanks of a screw thread
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.[1] This is a defining factor for the shape of a screw thread. Standard values include:

Name Code Angle Profile Standards
Most V-threads M 60° 120px including DIN 13 / ISO, NPT and UTS
Whitworth threads W 55°[2] 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
Rd 30° 120px[6] DIN 405 / DIN 20400
Acme thread[7] 29° 120px ASME/ANSI B1.5-1988[8]
Metric trapezoidal threads[1] Tr 30° 120px DIN 103
Buttress threads[7] S 45° 120px DIN 2781
German buttress threads[7] S 30° 120px DIN 513
Square threads[1] Sq 0° (parallel) 120px ?
Panzergewinde, "steel conduit thread" Pg 80° 120px DIN 40430
British Association (BA) thread BA 47° 30' = 47.5° 90px BS 93:2008
Löwenherz thread[9] 53° 8' ≈ 53.1°
Bodmer thread[10] 50°
Thury thread[11][12] 47° 30' = 47.5°

References

  • List of DIN standards

Notes

  1. 1.0 1.1 1.2 Bhandari 2007, p. 203.
  2. BS 84: 1956
  3. Knuckle Thread DIN 405
  4. Knuckle Thread DIN 20400
  5. Bornemann
  6. Knuckle thread
  7. 7.0 7.1 7.2 Bhandari 2007, p. 204.
  8. Machinery's Handbook (1996), pp. 1716.
  9. Löwenherz thread
  10. Bodmer thread
  11. 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.
  12. Thury thread

Bibliography