DIN 7991-10.9 / ISO 10642 Flat Head Countersunk Socket

Socket Cap Screws

10.9 Grade

*Flat Head Countersunk

S025 - 7991-10.9 Bare Steel
S029 - 7991-10.9 Zinc Plated

DIN 7991

ISO 10642

DIN 7991 Technical Drawing

*90° Countersink For Diameter M2 to M20 / 60° Countersink for Diameter M22 and Over

Diameter M2 M2.5 M3 M4 M5 M6 M8
b up to 125 12 14 16 18 22
b up to 200 24 28
t 0.75 0.8 1.2 1.8 2.3 2.5 3.5
e 2.3 2.87 3.44 4.58 5.72
s 1.3 1.5 2 2.5 3 4 5
k max. 1.2 1.5 1.7 2.3 2.8 3.3 4.4
d1 4 5 6 8 10 12 16
R.S. Torque (NM) 1.15 2.7 5.4 9.15 22
Length (mm) Bare Zinc Bare Zinc Bare Zinc Bare Zinc Bare Zinc Bare Zinc Bare Zinc
S025 S029 S025 S029 S025 S029 S025 S029 S025 S029 S025 S029 S025 S029
5 100 100 100
6 100 100 100 100
8 100 100 100 100 100 100 100 100 100
10 100 100 100 100 100 100 100 100 100 100 100
12 100 100 100 100 100 100 100 100 100 100 100
14 100 100 100 100 100 100
16 100 100 100 100 100 100 100 100 100 100 100
18 100
20 100 100 100 100 100 100 100 100 100 100
25 100 100 100 100 100 100 100 100 100 100
30 100 100 100 100 100 100 100 100 100
35 100 100 100 100 100 100 100 100
40 100 100 100 100 100 100 100
45 100 100 100 100 100 100
50 100 100 100 100 100
55 100 100
60 100 100 100
65 100
70 100 100 100
80 100 100
90 100
100 100
Order Number -> 7991-10.9 Bare 3x20 = S025-003-0020 | 7991-10.9 Bare 8x100 = S025-008-0100

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Diameter M10 M12 M14 M16 M18 M20 M24
b up to 125 26 30 34 38 42 46 54
b up to 200 32 36 40 44 48 52 60
t 4.4 4.6 4.8 5.3 5.5 5.9 10.3
e 6.86 9.15 11.43 11.43 13.72 13.72 16
s 6 8 10 10 10 12 14
k max. 5.5 6.5 7 7.5 8 8.5 14
d1 20 24 27 30 33 36 39
R.S. Torque (NM) 44 77 122 190 371
Length (mm) Bare Zinc Bare Zinc Bare Zinc Bare Zinc Bare Zinc Bare Zinc Bare Zinc
S025 S029 S025 S029 S025 S029 S025 S029 S025 S029 S025 S029 S025 S029
16 100
20 100 100 100 100
25 100 100 100
30 100 100 100 100 50 50
35 100 100 100 50 25
40 100 100 100 100 50 50 25
45 100 100 50 50 25
50 100 100 100 50 50 25 25
55 100 50 50 25
60 100 50 50 50 25 25
70 100 50 50 25 25 10
80 50 50 50 25 25 25 10
90 50 50 25 25 25 10
100 50 50 25 25 25 10
110 25 10
120 25 25 10
140 25 25
Order Number -> 7991-10.9 Bare 10x20 = S025-010-0020 | 7991-10.9 Bare 24x100 = S025-024-0100

NOTE

Limited Use:
Flat head countersunk socket cap screws DIN 7991 are not intended for high strength application. The purpose of producing them with a strength of the property class 10.9 is to increase the wear resistance of the sockets.
Tightening Procedure:
Insert the key into the socket and apply the torque on the nut while holding the key. Should however, the torque be applied on the screw itself it should be reduced accordingly.

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R.S. Torque = Recommended Seating Torque

Property Class 10.9
Hardness (HRC) 32-39
Tensile Strength (Mpa) 835 min.