CSFI

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Installation and Torque

With respect to installation and torque, there are three important design calculations and they are as follows:

Since there are wide ranges of sealing applications, more calculations may be required. If you are using standard sealing applications, then the calculations have already been done. On the other hand, if the application is unique, then these calculations will need to be tabulated. IMPORTANT: Calculations must be as accurate as possible to avoid an end result of leakage.

UNC

Nominal
Screw Size

Installation
Torque

(#4)

112 – 40 UNC – 2A

5 in-lbs

(#6)

138 – 32 UNC – 2A

9 in-lbs

(#8)

164 – 32 UNC – 2A

20 in-lbs

(#10)

190 – 32 UNF – 2A

23 in-lbs

(#10)

190 – 24 UNC – 2A

23 in-lbs

(#1/4)

250 – 20 UNC – 2A

75 in-lbs

(#5/16)

312 – 18 UNC – 2A

142 in-lbs

(#3/8)

375 – 16 UNC – 2A

263 in-lbs

Metric

Nominal
Screw Size

Installation
Torque

M3

0.6 Nm

M4

2.3 Nm

M5

4.0 Nm

M6

8.5 Nm

M8

18 Nm

M10

36 Nm

M12

60 Nm

*Please note that the above values are recommended average values only. Variations in local conditions and the material may require significant deviations from these recommended values.