Instruction Manual
D104223X012
A11 Valve
August 2017
9
Packing Adjustment and Shaft Bonding
WARNING
Personal injury could result from packing leakage. Valve packing was tightened before shipment; however, the packing
might require some readjustment to meet specific service conditions. Check with your process or safety engineer for any
additional measures that must be taken to protect against process media.
1.
For PTFE or graphite packing:
Tighten standard packing follower nuts only enough to prevent shaft leakage.
Excessive tightening of packing will accelerate wear and could produce higher rotating friction loads on the valve
shaft. If necessary, refer to the Packing Maintenance
section.
2.
For ENVIRO‐SEAL Packing Systems:
These packing systems will not require this initial re‐adjustment. Refer to the
separate ENVIRO‐SEAL Packing System for Rotary Valves Instruction Manual (
D101643X012
).
3. For hazardous atmosphere or oxygen service valves, read the following
Warning
, and provide the bonding strap
assembly mentioned below if the valve is used in an explosive atmosphere.
WARNING
The valve drive shaft is not necessarily grounded to the pipeline when installed. Personal injury or property damage could
result, if the process fluid or the atmosphere around the valve is flammable, from an explosion caused by a disk's charge of
static electricity from the valve components. If the valve is installed in a hazardous area, electrically bond the drive shaft to
the valve body.
Note
The packing is composed of all conductive packing rings (graphite ribbon packing) or partially conductive packing rings
(carbon‐filled PTFE female adaptor with PTFE V‐ring packing or graphite‐composition packing ring with PTFE/composition
packing) to electrically bond the shaft to the valve for hazardous area service. For oxygen service applications, and hazardous area
service where the standard packing doesn't provide sufficient shaft‐to‐valve body bonding, provide alternate shaft‐to‐valve body
bonding according to the following step.
4. Attach the bonding strap assembly (key 131, figure 4) to the shaft with the clamp (key 130, figure 4).
5. Connect the other end of the bonding strap assembly to the valve flange cap screws.
6. For more information, refer to the Packing Maintenance section below.
