Epson C Series, Maintenance Manual

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C12 Maintenance 2. General Maintenance
C Series Maintenance Manual Rev.2 441
2.4 Tightening Hexagon Socket Head Bolts
Hexagon socket head cap bolts (hereinafter, “bolts”) are used in places where mechanical
strength is required. These bolts are fastened with the tightening torque shown in the
following tables.
When it is required to refasten the bolts in some procedures in this manual (except special
cases as noted), use a torque wrench so that the bolts are fastened with appropriate tightening
torque as shown below.
Bolt Tightening Torque
See below for the set screw.
M3 2.0 ± 0.1 N
⋅
m (21 ± 1 kgf
⋅
cm) Set Screw Tightening Torque
M4
4.0 ± 0.2 N ⋅ m (41 ± 2 kgf ⋅ cm)
M4
2.4 ± 0.1 N ⋅ m (26 ± 1 kgf ⋅ cm)
M5
8.0 ± 0.4 N ⋅ m (82 ± 4 kgf ⋅ cm)
M5
3.9 ± 0.2 N ⋅ m (40 ± 2 kgf ⋅ cm)
M6
13.0 ± 0.6 N ⋅ m (133 ± 6 kgf ⋅ cm)
M6
8.0 ± 0.4 N ⋅ m (82 ± 4 kgf ⋅ cm)
M8 32.0 ± 1.6 N
⋅
m (326 ± 16 kgf
⋅
cm)
M10 58.0 ± 2.9 N
⋅ m (590 ± 30 kgf ⋅ cm)
M12 100.0 ± 5.0 N
⋅
m (1,020 ± 51 kgf
⋅
cm)
It is recommended to fasten the bolts aligned on a circumference in a crisscross pattern as
shown in the figure below.
1
5
3
7
2
6
4
8
Bolt hole
Do not fasten all bolts securely at one time.
Divide the number of times to fasten the bolts into
two or three and fasten the bolts securely with a
hexagonal wrench. Then, use a torque wrench to
fasten the bolts with tightening torques shown in the
table above.