Title:
RECOMMENDED ACTUATOR MOUNTING SCREW TIGHTENING TORQUES
NOTE: This chart is provided for guidance only. If in doubt, refer to screw manufacturer's data.
METRIC UNITS
Actuator
Size
Thread
Size (mm)
No. of
Screws
PCD
(mm)
020
030
050
070
080
090
100
120
140
150
160
180
200
300
4
5
5
8
8
10
10
12
16
16
24
30+
30+
30+
4
4
6
4
6
4
4
4
4
4
4
4
8
8
25.50
31.10
34.90
50.90
50.80
65.00
102.00
77.80
98.80
140.00
152.70
226.30
226.30
226.30
Thread
Size
No. of
Screws
PCD
(inches)
4
4
6
4
6
4
4
4
4
4
4
4
8
8
1.00
1.22
1.37
2.00
2.00
2.56
4.02
3.06
3.89
5.51
6.01
8.91
8.91
8.91
Recommended Tightening
Torque (Nm)
@ 5.5 Bar @ 7 Bar
1.7
4.0
4.6
18.0
16.7
35.7
36.3
83.5
204.0
244.0
455.0
840.0
778.0
1170.0
2.4
5.0
6.0*
23.0
21.0
45.0
46.0
104.0*
260.0*
306.0*
570.0*
1050.0
980.0
1170.0
ENGLISH UNITS
Actuator
Size
029
039
059
079
089
099
109
129
149
159
169
189
209
309
8-32 UNC
10-24 UNC
10-24 UNC
5/16 UNC
5/16 UNC
3/8 UNC
3/8 UNC
1/2 UNC
5/8 UNC
5/8 UNC
7/8 UNC
1 1/8 UNC+
1 1/8 UNC+
1 1/8 UNC+
Recommended Tightening
Torque (lbf.in)
@ 80 psi @ 100 psi
17
32
38
157
144
310
316
770
1800
2160
3660
7090
6560
9834
21
40
48*
197
180
390
395
980*
2250*
2700*
4600
8870
8195
9834
- The above data assumes that the mounting surfaces are flat and exhibit a coefficient of friction 0.2
(e.g. two painted surfaces) and provides a safety factor of 2 to allow for shock loading.
- Screw thread engagement should be at least 75% of the maximum available.
- The torques stated assume full double acting actuator torque at the air pressures specified. For
spring return or reduced air supply pressures, these torques can be reduced in proportion to the
reduction in actuator output torque.
- The type of screw (i.e. Hexhead or socket head) does not affect the recommended torque.
For sizes marked thus "*" use high tensile steel screws (minimum grade 8.8 BS3692) or
high tensile stainless steel screws (minimum grade A4 ISO3506).
For M30 or 1 1/8 UNC marked thus "+" use carbon steel only. Ensure that if zinc plating is
applied to screws, it does not suffer from "hydrogen embrittlement".
For all other sizes use Grade 8.8 carbon steel, A2 or A4 stainless steel specification screws.
Issue Signed
H
Date
D.G.W. 19/02/14
AR5881
Trading Estate Farnham Surrey England
Doc.No. TD111
Page 1 of 1
KF – 227 – 10/94