Siemens SIMOTICS GP Operating Instructions Manual page 77

Terminal box Screws:
Frame Size
143/145,
182/184,
213/215,
254/256,
284/286.
324/326,
364/365,
404/405,
444/445, 447 y
449
A specific condition of use is included to indicate that fasteners
should only be replaced by identical ones.
Tightening Torques in motors
All screws tightening torques for screws in threaded joints of
bearing shields, housing and bearing caps should have the following
torques according to the size of the screw
Diameter
(Inches)
5/32"
3/16"
1/4"
5/16"
3/8"
7/16"
1/2"
5/8"
3/4"
7/8"
Unrestricted
Screws
1 / 4" - 20NC
5 / 16" – 18NC
HEXAGONAL SCREW HEAD GRADE 5
Threads per inch
32
24
20
18
16
14
13
11
10
9
Grade
(mínimum)
5
5
.
Minimum
(Nm)
3.1
4.4
10.7
21.7
38.2
61.0
92.0
184.0
322.0
450.0
77
Tensile Strength
(minimum)
(PSI)
120,000
120,000
Nominal Maximum
(Nm) (Nm)
3.5 3.8
4.9 5.4
11.9 14.2
24.2 29.2
42.5 47.0
67.9 75.0
103.0 114.0
204.0 224.4
358.0 393.0
490.0 520.0
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