T-156
Table 17-5 Gears Without Case Hardening
HB
HV
37
42
46
49
55
60
39
42
45
48
51
55
58
61
64
68
71
74
77
81
51
55
58
61
64
68
71
74
77
81
84
87
90
93
71
74
77
81
84
87
90
93
97
100
103
106
110
113
117
126
136
147
157
167
178
189
200
210
221
231
242
252
263
167
178
189
200
210
221
231
242
252
263
273
284
295
305
231
242
252
263
273
284
295
305
316
327
337
347
358
369
380
120
130
140
150
160
170
180
190
200
210
220
230
240
250
160
170
180
190
200
210
220
230
240
250
260
270
280
290
220
230
240
250
260
270
280
290
300
310
320
330
340
350
360
10.4
12.0
13.2
14.2
15.8
17.2
13.8
14.8
15.8
16.8
17.6
18.4
19.0
19.5
20
20.5
21
21.5
22
22.5
18.2
19.4
20.2
21
22
23
23.5
24
24.5
25
25.5
26
26
26.5
25
26
27.5
28.5
29.5
31
32
33
34
35
36.5
37.5
39
40
41
G
S25C
H
G
S35C
H
SC37
SC42
SC46
SC49
SCC3
G
S43C
H
G
S48C
H
G
S53C
|
S58C
H
G
S35C
H
G
SMn443
H
G
S43C
H
G
SNC836
|
SCM435
H
G
S53C
|
S58C
H
G
SNCM439
H
G
S48C
H
G
SCM440
H
Tensile Strength
Lower limit
kgf/mm2
(Reference)
sF lim
kgf/mm2
Arrows indicate the ranges
Material
Cast
Steel
Gear
Normalized
Carbon
Steel
Gear
Quenched
and
Tempered
Carbon
Steel
Gear
Quenched
and
Tempered
Alloy
Steel
Gear
Hardness