Sechskantschrauben mit Sechskantmuttern für stahlkonstruktionen

Supersedes January 1971 edition.

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.

The new widths across flats 18mm and 34mm as specified in ISO 272 should be used instead of the previous widths across flats 19mm and 32mm for thread sizes M12 and M22. It is intended to omit the obsolescent widths across flats by 1 November 1994 at the latest.

Dimensions in mm

1        Scope and field of application

This standard specifies requirements for M12 to M30 hexagon head bolts for supply with hexagon nut, assigned to product grade C, for use in structural steel bolting. These bolts shall always be used together with A type washers as specified in DIN 7989 (see clause 6).

2        Dimensions

                                         Continued on pages 2 to 6

4        Designation

Designation for an M16 hexagon head bolt of nominal length, l=50mm, for supply with hexagon nut (Mu)1), of property class 4.6:

Hexagon head bolt DIN 7990-M16×50-Mu-4.6

The designation signifies that the widths across flats for sizes M12 and M22 are those hitherto specified, i.e. 19mm and 32mm. If bolts are to be supplied with a new width across flats as specified in ISO 272 (18 mm or 34 mm), the width across flats (SW) shall be included in the designation, e.g.

Hexagon head bolt DIN 7990-M12×50-Mu-SW18-4.6

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

1)    Where the bolts are supplied in given quantities, the nuts may accompany the consignment in bulk packaging.

Page 8 DIN 7990

Standards referred to

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

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

DIN 78         Thread ends and lengths of projection of bolt ands for ISO metric threads as specified in DIN 13

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

DIN 267 Part 5  Fasteners; technical delivery conditions; acceptance inspection (modified version of ISO 3269, 1984 edition)

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

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

DIN 555      M5 to M100×6 Hexagon nuts; product grade C

DIN 400 Part 2 Tabular layout of article characteristics for bolts, screws and nuts

DIN 7989    Washers for structural steel bolting

ISO 272     Fasteners; hexagon products; widths across flats

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

ISO 4034        Hexagon nuts; product grade C

ISO 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

Previous editions

DIN 1050 Supplement 2: 12.43; DIN 7990: 10.56, 03.63, 01.71.

Amendments

The following amendments have been made to the January 1971 edition.

a)    Widths across flats 18mm and 34mm as specified in ISO 272 have been adopted additionally for thread sizes M12 and M22.

b)    A note on the use of obsolescent widths across flats has been included.

c)    The scope of the standard has been extended to include hexagon nuts as specified in ISO 4034.

d)    Nut height m is no longer specified.

e)    Specifications for the bearing face design have been included.

f)    Limits of size are now specified.

g)    Lengths l_s and l_g are now specified.

h)    Property class 3.6 is no longer specified.

j)    Property class 5.6 has been adopted.

k)    Hexagon bolts are now to be hot dip galvanized as specified in DIN 267 Part 10.

l)    The standard designation has been amended by including the property class.

m)    Dimension d2 is no longer specified.

n)    The standard has been editorially revised.

International Patent Classification

E 04 B 1/38

F 16 B 35/00

F 16 B 37/00

F 16 B 5/02

F 16 B 23/00