Sechskantschrauben mit Schaft; Gewinde M1, B bis M39; Produktklassen A und B

This standard, together with DIN ISO 4014, September 1987 edition, supersedes the December 1982 edition.

This standard should be used together with ISO 4014, For details, see Explanatory notes, it is intended to withdraw the present standard by 1 July 1992 at the latest.

In keeping with current practice in standards published by the International Organization for Standardization (ISO), a comma has been used throughout as the decimal marker.

Dimensions in mm

1 Field of application

This standard specifies requirements for M1.6 to M36 hexagon head bolts assigned to product grade A for thread sizes up to and including M24 and lengths smaller than 10d or 150mm, and assigned to product grade B for thread sizes above M 24 or lengths exceeding 10d or 150mm.

If , in special cases ,bolts are to comply with specifications other than those given in this standard, e.g. regarding nominal lengths, these shall be selected in accordance with the appropriate standard.

2 Dimensions

                                            Continued on pages 2 to 7

4  Designation

Designation of an M 12 hexagon head bolt of nominal length, l= 80 mm, with material assigned to property class 8.8: Hexagon head bolt DIN 931- M12×80-8.8

If product grade A is required for sizes up to M24 with lengths over 15o mm or with l greater than 10d, or for sizes above M 24 , then this shall be indicated in the designation by adding ‘A’ , e.g.

Hexagon head bolt DIN 931-M30×100-8.8- A

DIN 962 shall apply with regard to the designation of designs and types ,with additional details to be given when ordering, DIN 6900 shall apply with regard to the designation of types with captive components .

The DIN 4000-2-1 tabular layout of article characteristics shall apply to bolts covered in this standard .

Footnotes for the tabbies on pages 2 to 4:

1) P= pitch of thread (coarse pitch thread).

2) For l≤125mm.

3) For l＞125mm≤200mm.

4) For l＞200mm.

Page 6 DIN 931 Part 1

Appendix A

Additional thread sizes for spare parts

The previous thread sizes M 1,7, M2,3 and M 2,6, which are not included the International selection of screw thread for bolts, screws and nuts, shall no longer be used. In consideration of existing documents and of the demand for spare parts, they may, however, still be ordered in accordance with DIN 931, November 1970 edition. The table below shall apply with regard to the dimensions o bolts (DIN 13 Parts 1 and 15 applying with regard to screw threads).

Standards referred to and other documents

DIN 13 Part 1    ISO metric screw threads; 1 mm to 68 diameter coarse pitch threads; nominal sizes

DIN 13 Part 12    ISO metric screw threads; coarse and fine pitch threads with diameters from 1 to 300 mm; selection for diameters and pitches

DIN 13 Part 15    ISO metric screw threads; fundamental deviations and tolerances for screw threads of 1 mm diameter and larger

DIN   78       Thread ends and of projection of bolt ends ISO metric threads in accordance with DIN 13

DIN 267 Part 1    Fasteners; technical delivery conditions; general requirements

DIN 267 Part 2    Fasteners; technical delivery conditions; finish and dimensional accuracy

DIN 267 Part 5    Fasteners; technical delivery conditions; acceptance inspection

DIN 267 Part 9   Fasteners; technical delivery conditions; electroplated components

DIN 267 Part 10  Fasteners; technical delivery conditions; hot-dip galvanized components

DIN 267 Part 11  Fasteners; technical delivery conditions; with addenda to ISO3506; corrosion resistant stainless steel components

DIN 267 Part 18  Fasteners; technical delivery conditions; non-forrous metal components

DIN 267 Part 19    Fasteners; technical delivery conditions; surface discontinuities on bolts Supplement 1 to

DIN 931 Part 1    Hexagon head bolts with shank; masses

DIN 963         Bolts, screws, studs and nuts; designations; types and finishes

DIN 4000 Part 2  Tabular layout of article characteristics for bolts, screws and nuts

DIN 6900        Screw and washer assemblies

DIN 7500 Part 1 Thread rolling screws for ISO metric threads; dimensions, requirements, testing

DIN 898 Part 1     Mechanical properties of fasteners; bolts, screws and studs

DIN 4759 Part 1    Tolerances for fasteners bolts, screws, and nuts with thread diameters≥1,6 and≤150 mm and product grades A, B and C

*) Withdrawn in 1982

DIN 931 Part 1 Page 7

Previous editions

DIN 932 Part 1 and Part 2:01.26; DIN 532: 11.29x; DIN Kr 551: 11.35,11.36;

DIN 931 Part 2: 01.28, 04, 42;   DIN 931:12.67, 11.70; DIN 931 Part 1: 01.26, 04.42, 12.52, 03.63, 07.62.

Amendments

The following amendments have been made to the July 1982 edition.

a) A note on the period of validity of this standard has been included.

b) The specification regarding the underhead fillet has been deleted.

c) For sixes M 10, M 12, M 14 and M 22, the widths across flats specified in ISO 272 have been deleted.

d) A reference line for the determination of the bearing face diameter, d_w has been included.

Explanatory notes

For more than 20 years efforts have been directed towards the achievement of the international interchangeability of fasteners by preparing international standards for the product concerned. ISO Standards have now been published for the most important types of fasteners (see ISO Standards Handbook 18).

However, international efforts only serve a useful purpose if national standards are adapted as far as possible to international standards, or, ideally, replaced by them. Current DIN Standards, but still differ in some respects, as for instance in the widths across flats for hexagon products. The Federal Republic of Germany adopted international Standard ISO 272 on widths across flats as national standard DIN ISO 272 in October 1979. Nevertheless, widths across flats deviating from DIN ISO 272 are still being used in Germany for nominal sizes M 10, M 12, M 14 and M 22. The table below compares the previous widths across flats with the new ones specified for the four nominal sizes referred to.

The manufacturers and users of hexagon products participating in the work of the Normenausschub Mechanische Verbindungselemente (Festeners Standards Committee), together with representatives of the dealers in fasteners, have decided to introduce the new widths across flats in all relevant product standards. Since experience has shown, that the introduction of the new widths across flats has not been advanced by their inclusion in DIN Standards merely as preferred alternatives to the previous widths across flats, the following decisions have been reached to accelerate the changeover procedure.

Supplementary to current DIN Standards specifying the previous widths across flats, DIN ISO Standards dealing with the same products will, wherever ISO Standards are available, be published which, besides introducing a number of other minor amendments, will specify the new widths across flats conforming to ISO 272, In both DIN and Din ISO Standards attention will be drawn to the fact that the relevant ISO Standards are to be preferred and that the DIN Standard is to be replaced after a transition period of 5 years.

If no relevant ISO Standard is available, the DIN Standard will contain a foreword stating that the previous width across flats specifications are to be with drawn after a transition period of 5 years and replaced by those specified in ISO 272.

This sets a time limit for both manufacturer and user of hexagon products by which the changeover to the new widths across flats must be effected. The responsible committee is of the opinion, that it will still be possible after this period to obtain fasteners complying with the superseded specifications as spare parts.

In some cases, the replacement of the previous DIN Standards by the relevant ISO Standards will have further consequences, besides the changeover to the new widths across flats, attention being drawn to this circumstance in the national foreword of the relevant DIN ISO Standards. These consequences result from the fact that the ISO Standards have not yet reached the same level of completeness the DIN Standards. Thus a number of nominal sizes, as well as several product specifications for fine pitch threads are not found in the ISO product standards. Furthermore, ISO Standards on technical delivery conditions are still in the initial stages, so that specific requirements are still subject to separate agreement when ordering products in accordance with ISO Standards, as they are not included in the designation for order purposes.

Besides these consequences, which are of importance when applying the new ISO Standards, the amendment of the widths across flats also have a number of consequences as regards the use of the new products which the designer must take into consideration, Besides the amended assembly sizes, this applies above all to the different surface pressure for the bearing area of the nut or the heads of the bolts. These difficulties are discussed in Recommendation VDA 262*) published by the Verband der Automobilindustrie e.V.(German Automobile Manufacturers Association).

International Patent Classification

F 16 B 35/00

*) Obtainable from: Dokumentation Kraftfahrwesen e.V., Grunerstraße 5, D-7140 Ludwigsburg: