Advertisement
February 2014
Flange bolts
Do not bolt one side at a time. Tighten each side simultaneously. Example:
1. Snug upstream
2. Snug downstream
3. Tighten upstream
4. Tighten downstream
Do not snug and tighten the upstream side and then snug and tighten the
downstream side.
Failure to alternate between the upstream and downstream flanges when
tightening bolts may result in liner damage.
Suggested torque values by sensor line size and liner type are listed in
page 12
. Consult the factory if the flange rating of the sensor is not listed.
Tighten flange bolts on the upstream side of the sensor in the incremental
sequence shown in
Repeat the process on the downstream side of the sensor. For sensors with more
or less flange bolts, tighten the bolts in a similar crosswise sequence. Repeat this
entire tightening sequence at 40%, 60%, 80%, and 100% of the suggested torque
values or until the leak between the process and sensor flanges stop.
If leakage has not stopped 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 the user 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. Sensors require a second
tightening 24 hours after the initial installation. Over time, sensor liner materials
may deform under pressure.
Figure 9. Flange bolt torquing sequence
For torque values not listed in Table 1, Table 2, or Table 3, contact technical
support.
Figure 9 on page 11
to 20% of the suggested torque values.
Quick Start Guide
Table 1 on
11
Advertisement
