mainero 2240 - Page 68

68
VALUES OF IT PRESSES OF THE METRIC SCREWS
DO NOT USE these values if the especial application requires a different value. The values are related use
in general. Verify periodically the screws. The screws of controlled breaking were designed to brake under
certain load. Replace the screws of controlled breaking always with screws of the same class.
The mechanism of xing has to be replaced by others with similar or higher class. In this case the screws
have to be screwed with the original value.
Prove if the thread of the xings are clean and that they start to screw correctly. This prevent the fail of the
screws while screwing.-
Screw the nuts from plastic or metal con 50% of the value indicated for “dry” xing. Screw the crenellated
nuts with the highest indicated value.
a “ Greased” means, that screws were oiled with motor oil or that the screws were oiled or got covered with
phosphate. “Dry” means, that they used normal xings or galvanized without lubrication.
4.8
4.8
4.8
5
5
8.8
8.8 9.8
9.8
10
10
8.8 9.8
5 10
10.9
10.9
10.9
10
10
10
12.9
12.9
12.9
12.9
12.9
12
12
12
Grade and
marks in
heads
Grade and
marks in
nuts
Diameter
class 4.8 class 8.8 o 9.8 class 10.9 class 12.9
greased
a
dry
a
greased
a
dry
a
greased
a
dry
a
greased
a
dry
a
Nm Lb-ft Nm Lb-ft Nm Lb-ft Nm Lb-ft Nm Lb-ft Nm Lb-ft Nm Lb-ft Nm Lb-ft
M6
M8
M10
M12
M14
M16
M18
M20
M22
M24
M27
M30
M33
M36
4.8
12
125
40
63
100
135
190
260
330
490
675
900
1150
3.5
60
92
29
47
73
100
140
290
250
360
490
675
850
6
15
29
50
80
125
175
240
330
425
625
850
1150
1450
4.5
11
21
37
60
92
125
180
250
310
450
625
850
1075
9
22
43
75
120
190
260
375
510
650
950
1300
1750
2250
6.5
16
32
55
88
140
195
275
375
475
700
950
1300
1650
11
28
55
95
150
240
330
475
650
825
1200
1650
2200
2850
8.5
20
40
70
110
175
250
350
475
600
875
1200
1650
2100
13
32
63
110
175
275
50
80
125
924
1350
1850
2500
3200
9.5
24
47
80
130
200
37
60
92
675
1000
1350
1850
2350
17
40
80
140
225
350
475
675
925
1150
1700
2300
3150
4050
12
30
60
105
165
255
350
500
675
850
1250
1700
2350
3000
15
37
75
130
205
320
440
625
850
1075
1600
2150
2900
3750
11.5
28
55
95
150
240
325
460
625
800
1150
1600
2150
2750
19
47
95
165
260
400
560
800
1075
1350
2000
2700
3700
4750
14.5
35
70
120
190
300
410
580
800
1000
1500
2000
2750
3500