Consolidated Tech Man - Holo-Krome

TABLE 58 HOLO-KROME METRIC BUTTON HEAD AND FLAT COUNTERSUNK HEAD
SOCKET CAP SCREWS
MECHANICAL PROPERTIES
Standard Metric Holo-Krome Alloy Steel Button and Flat Countersunk
Head Cap Screws are manufactured from Holo-Krome analysis high
grade alloy steel, hardened and tempered to provide the following
mechanical properties.
The tensile strength of the screws, because of head configuration are
based on 980 MPa as shown in ASTM F 835M.
NOTES FOR TABLE 58
86
TABLE 58 HOLO-KROME METRIC BUTTON HEAD AND
FLAT COUNTERSUNK HEAD SOCKET CAP SCREWS
NOMINAL
SIZE AND THREAD
PITCH
MM
M3 x 0.5
M4 x 0.7
M5 x 0.8
M6 x 1
M8 x 1.25
M10 x 1.5
M12 x 1.75
M16 x 2
M20 x 2.5
THREAD
STRESS AREA
(mm 2 )
5.03
8.78
14.2
20.1
36.6
58.0
84.3
157
245
BUTTON HEAD CAP SCREWS ARE DESIGNED FOR LIGHT FAS-
TENING APPLICATIONS ONLY, SUCH AS SHEETMETAL COVERS,
PLASTIC GUARDS, ETC. THEY SHOULD NOT BE USED IN CRITI-
CAL HIGH STRENGTH APPLICATIONS WHERE SOCKET HEAD
CAP SCREWS SHOULD BE USED.
The mechanical properties listed are for screws tested at normal room
temperatures. In applications where the temperature are considerably
Tensile Strength * .............................................. 1220 MPa
Yield Strength* ................................................... 1100 MPa
Elongation in 2 inches* ...................................... 8%
Reduction of Area* ............................................. 35%
Hardness ............................................................ 38 Rockwell C min.
*Apply to cylindrical test specimens only.
TENSILE
STRENGTH
(kN)
4.93
8.60
13.9
19.7
35.9
56.8
82.6
155
240
TABLE 59 TIGHTENING TORQUE - N•m
NOMINAL
SIZE AND THREAD
PITCH
MM
M3 x 0.5
M4 x 0.7
M5 x 0.8
M6 x 1
M8 x 1.25
M10 x 1.5
M12 x 1.75
M16 x 2
M20 x 2.5
HEX KEY SIZE
(mm)
2
2.5
3
4
5
6
8
10
12
BUTTON HEAD
1.25
2.9
5.9
10
24
48
84
207
SINGLE SHEAR
STRENGTH
(THREAD SEC.)
(kN)
3.81
6.65
10.7
15.2
27.7
43.9
63.9
119
185
1.85
3.4
6.9
12
28
56
99
246
400
Torque to tighten screw with key, not by turning nut.
These torques apply to standard black screws in rigid joints, when torqued with standard
hex keys or bits.
above or below room temperature the effect of the temperature on the
screw strength must be considered. Short time tensile, creep and
stress relaxation should be considered for applications where the
temperature exceeds 204° C. Lower ductility, impact strength and
fatigue life must be considered for screws subject to temperatures
below -29° C.
Applicable Standards and Specifications
ASTM F 835M
MAX. TIGHTENING
TORQUE
(N . m)
FLAT COUNTERSUNK
HEAD
MAX. TIGHTENING
TORQUE
(N . m)