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Installing/mounting
4.4 Installation instructions
SITRANS LR250 with FOUNDATION FIELDBUS
Operating Instructions, 09/2021, A5E32221411-AH
33
Flange bolting: recommended torque
Pressure class
Nominal pipe size
(NPS)
Number of bolts
Recommended torque
(Nm)
ASME B16.5, Class 150
2"
4
30 – 50
3"
50 – 70
4"
8
40 – 60
6"
70 – 90
EN1092-1, PN16 /
JIS B 2220, 10K
DN50/50A
4
30 – 50
DN80/80A
8
DN100/100A
DN150/150A
60 – 80
Flange bolting instructions:
1.
Use cross-pattern sequence as shown.
2.
Check uniformity of the flange gap.
3.
Apply adjustments by selective tightening if required.
4.
Torque incrementally until desired value is reached.
5.
Check/re-torque after 4 to 6 hours.