Emerson Rosemount 3408 - Torque specifications

2. Tighten the bolts and nuts (see Table 3-1).
Note
• Re-tighten after 24 hours and again after the first temperature
cycle.
• Check at regular intervals and re-tighten if necessary.
3.2 Torque specifications
The conditions used for the calculation are:
• Standard mating metal flange
• A193 B8M Cl.2 / A4-70 bolt material
• Friction coefficient of μ=0.16
Low strength bolt and non-metallic mating flange may require lower
tightening torque.
Table 3-1: Torque Values for Process Seal Antenna, lb-ft (N-m)
Process connection
size
Process connection rating
ASME B16.5 EN1092-1 JIS B2220
Class 150 Class 300 PN16 PN40 10K 20K
2-in./DN50/50A 29 (40) 52 (70) 26 (35) 29 (40) 18 (25) 37 (50)
3-in./DN80/80A 33 (45) 48 (65) 37 (50) 41 (55) 22 (30) 70 (95)
4-in./DN100/100A 59 (80) 52 (70) 37 (50) 74 (100) 26 (35) 74 (100)
6-in./DN150/150A 66 (90) 66 (90) 74 (100) 136 (185) 74 (100) N/A
September 2022 Quick Start Guide
Quick Start Guide 7