Emerson Rosemount 8732EM, Reference Manual

Page: 20 / 254

If leakage occurs at the suggested torque values, the bolts can be tightened in additional
10% increments until the joint stops leaking, or until the measured torque value reaches
the maximum torque value of the bolts. Practical consideration for the integrity of the liner
often leads to distinct torque values to stop leakage due to the unique combinations of
flanges, bolts, gaskets, and sensor liner material.
Check for leaks at the flanges after tightening the bolts. Failure to use the correct
tightening methods can result in severe damage. While under pressure, sensor materials
may deform over time and require a second tightening 24 hours after the initial
installation.
Flange bolt torquing sequence Figure 3-6:
Prior to installation, identify the lining material of the flow sensor to ensure the suggested
torque values are applied.
Lining material Table 3-1:
Fluoropolymer liners Other liners
T - PTFE P - Polyurethane
F - ETFE N - Neoprene
A - PFA L - Linatex (Natural Rubber)
K - PFA+ D - Adiprene
Suggested flange bolt torque values for Rosemount 8705 (ASME) Table 3-2:
Size
Code
Line Size
Fluoropolymer liners Other liners
Class 150
(pound-feet) Class 300
(pound-feet) Class 150
(pound-feet) Class 300
(pound feet)
005 0.5-in. (15 mm) 8 8 N/A N /A
010 1-in. (25 mm) 8 12 6 10
015 1.5-in. (40 mm) 13 25 7 18
020 2-in. (50 mm) 19 17 14 11
Sensor Installation
14 Rosemount ® 8732EM Transmitter with HART Protocol Reference Manual