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Dowels Pins

Dowels Pins

DIN 7, DIN 6325, DIN 7979D, ISO 2338, ISO 8734

Dowels are solid pins, usually precision ground to narrow limits to permit accurate fitting, they are traditionally used to hold parts together in a fixed alignment, relying on the tightness of fit to stay in place.
Some applications for solid pins require clearance or transition fits on at least one of the components to be fastened.
There are three factors that determine the size of hole needed:

  • The Dimensional Standard of the dowel
  • The tolerance on the dowel
  • The tightness of fit needed
  • The hardness of the components into which the dowel is to be fitted

Dowel Pin Standards

DIN 7 DIN 6325 DIN 7979D ISO 2338 ISO 8734

Dowel Pin Tolerances And Fits

Our range standardises on m6 tolerance, which corresponds to the ISO and DIN standards*. The m6 tolerance is a 'plus tolerance' range and is normally used for interference fits. Also available are the minus tolerance ranges, h7 and h8

Dowel Pin Hole Tolerance Guide

Hole material Hardened steel Mild steel Aluminium / zinc / brass
Interference fit Pin Ø less 5 microns Pin Ø less 25 microns Pin Ø less 35 microns
Transition fit Pin Ø less 2 microns Pin Ø less 5 microns Pin Ø less 5 microns
Clearance fit Pin Ø plus 25-60 microns Pin Ø plus 25-60 microns Pin Ø plus 25-60 microns

Fitting Dowels Into Blind Holes

When a dowel is interference-fitted into a blind hole, it increases the pressure of the air trapped in the hole. It is recommended that the dowel should have an air release flat ground along its full length to prevent the dowel being ejected under the pressure of compressed air, or bursting the component into which it is driven.

Dowel Pin Materials

Through hardened steel 100Cr6, WS 1.3505 hardened and tempered to HV 550-650
Mild steel, unhardened WS 1.0718 (9SMnPb28)
Stainless a2 WS 1.4305 or 303S31
Stainless a4 WS 1.4571 or 316S11

Material Grades

  • Carbon Steel 1018, 1020, 1040, 1045
  • Alloy Steel 4130, 4140, 4142, 4340, 6150, 8620
  • Chrome Moly Steel 25CRMO4, 21CRMOV5-7, 42CRMO4, 42CRMOV4-6
  • Austenitic Stainless Steel 301, 302, 303, 304, 316, 317, 321, 310, 309, 329, 347 & 348
  • Martensitic / Ferritic Stainless Steel 403, 405, 409, 410, 414, 416, 418, 420 & 430F
  • Super Austenitic Stainless Steel 904l, 254-Smo, 253Ma, Alloy 20, Sanicro Alloy 28, Al-6xn, 310Moln, Alloy 230, Alloy 330 , Alloy 333
  • Precipitation Hardening Stainless Steel Alloy A-286, A453 GRADE 660, 17-4 PH, 15-5 Ph , 15-7 Ph, 17-7 Ph
  • Nitronic 50 , 60 ( xm-19), 30, 32, 33, 40
  • Duplex 32205 (F60), 31803 (F51);Super Duplex 32750 ( F53) , 32760 (Zeron 100), (F55), 329, Ferralium 255, 255FG46
  • Inconel 600, 601, 602, 603, 617, 625, 686, 702, 713, 718, 725, 738, 740, 783, X-750, 701, 901, 939
  • Incoloy 800, 800H, 800HT, 825, 925, 926, 945
  • Hastelloy C276, C22,C-2000,C4,B, B2, B3, G30, X, N
  • Monel Alloy 400, K-500, R405
  • Nimonic Alloy 80A, 90, 105, 115, 263
  • Titanium Grade1, 2, 3, 4, 5, 6, 7,8, 9, 11, 12, 19,23
  • Nickel 200, 201
  • Copper Nickel 70/30, 90/10
  • Silicon Bronze C651, C655, C656
  • Cobalt Alloys Invar 36 / 42, Waspalloy, MP35N / 159, Stellite 3/6/12/21, Rene 41, L605
  • Molybdenum Grade 361/363/364/365
  • Durehete 900/950/1055, JETHETE X19/M152, Hiduron 130/190, Tantalum, Zircoloy, Aluminium Alloy 2024, 6061, 7075