4 tightening torques, Tightening torques, Series nks-c, nksp-c, nkl-c, nklp-c – Richter NKLP-C Series Butterfly Valves User Manual
Page 6
Series NKS-C, NKSP-C, NKL-C, NKLP-C
Page 6
9520-072-en
Revision 01
TM 8176
Edition 03/2011
1.4 Tightening torques
All screws greased, tighten in diametrically
opposite sequence!
After the plant has been started up (especially with the
first temperature load) the tightening torques must be
checked and the correct value set again.
The tightening torques for pipe screws and body
screws mentioned must not be exceeded. For an ex-
ception, see Section 8, flange connection valve/pipe
is leaking.
The following tightening torques are recommended:
Pipe screws, flanges to ISO/DIN
Standard threaded hole
Flange
nom. size
Screws
Tightening torque
[mm]
[ISO/DIN]
[Nm]
50
4 x M16
35
65
8 x M16
40
80
8 x M16
45
100
8 x M16
50
125
8 x M16
60
150
8 x M20
70
200
8 x M20
85
250
12 x M20
95
300
12 x M20
105
350
16 x M20
145
400
16 x M24
165
450
20 x M24
185
500
20 x M24
215
600
16 x M27
230
700
24 x M27
280
750
---
---
800
24 x M30
380
900
28 x M30
460
1000
28 x M33
500
Pipe screws flanges ISO/DIN drilled to ASME Class
150 Standard threaded hole
Flange nom.
size
Screws
Tightening
torque
[mm]
[inch]
[ASME]
[Nm]
[in-lbs]
50
2“
4 x
⅝“-11UNC
35
310
65
2½“
4 x
⅝“-11UNC
40
354
80
3“
4 x
⅝“-11UNC
45
398
100
4“
8 x
⅝“-11UNC
50
442
125
5"
8 x ¾“-10UNC
60
532
150
6“
8 x ¾“-10UNC
70
620
200
8“
8 x ¾“-10UNC
85
753
250
10“
12 x
⅞“-9UNC
95
842
300
12“
12 x
⅞“-9UNC
105
931
350
14“
12 x 1“-8UNC
145
1285
400
16“
16 x 1“-8UNC
165
1463
450
18"
16 x 1
⅛“-7UNC
185
1640
500
20"
20 x 1
⅛“-7UNC
215
1906
600
24"
20 x 1¼“-7UNC
230
2039
700
28"
28 x 1¼“-7UNC
280
2482
---
30"
28 x 1¼“-7UNC
300
2660
800
32"
28 x 1½“-7UNC
380
3369
900
36"
32 x 1½“-6UNC
460
4078
1000
40"
36 x 1½“-6UNC
500
4433
Pipe screws,
flanges to ISO/DIN,
through hole
NKS-C+NKSP-C from size DN 350 (14") upwards
with lug-style body and through hole
Flange
nom. size
Screws
Tightening
torque
[mm]
[ISO/DIN]
[Nm]
50
4 x 18
35
65
8 x 18
40
80
8 x 18
45
100
8 x 18
50
125
8 x 18
60
150
8 x 22
70
200
8 x 22
85
250
12 x 22
95
300
12 x 22
105
350
16 x 22
145
400
16 x 26
165
450
20 x 26
185
500
20 x 26
215
600
20 x 30
230
700
24 x 30
280
750
---
---
800
24 x 33
380
900
28 x 33
460
1000
36 x 42
500