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Instruction Manual
D104358X012
1.
Isolate the control valve from the line pressure.
2.
Release
pressure and drain process media from both sides of the control valve.
3. If using a power actuator, also shut off all pressure lines to the power actuator, and release all pressure from the
actuator. Use lock‐out procedures to be sure that the above measures stay in effect while working on the
equipment.
4.
Disconnect the operating lines from the actuator and any leak‐off piping from the bonnet.
5.
Disconnect the stem connector and then remove the actuator from the valve by unscrewing the yoke locknut.
6. Remove any travel indicator parts and stem locknuts from the valve stem threads.
7. Remove the packing nut (figure 3, 4, or 5, key 3) from bonnet.
8. Remove packing parts from bore using a packing extraction tool and check for damage to valve stem or packing
box bore.
9. Install the ENVIRO-SEAL packing parts into the packing box. Use figure 3, 4, or 5 to ensure the packing parts and
spring pack are assembled in correct order.
10. Install the spring pack assembly with the attached springs, onto the stem, ensuring the Belleville springs are
stacked properly and packing box parts are assembled in the correct order (figures 3, 4, or 5). Packing parts cannot
function properly if the Belleville springs or other packing parts are not stacked correctly.
11. Lubricate the packing nut (figure 3, 4, or 5, key 3) with anti-seize lubricant and install hand tight.
Tightening Procedures - Packing Nut
1. To achieve maximum benefit from the ENVIRO-SEAL packing system, the packing nut must compress the Belleville
springs to their "target load." The target load is the point where the Belleville springs are designed for optimum
performance, when compressed to 85% of their maximum deflection, or nearly flat. (Maximum deflection is when
the springs are 100% compressed, or completely flat). To obtain the target load of 85% compression of maximum
deflection, perform the following:
D Tighten the packing nut until the Belleville springs are compressed 100% (or completely flat), as detected by a rapid
increase in nut torque.
D For PTFE or Duplex packing, loosen packing flange nut 1/2 turn (180_ of rotation).
D For Graphite ULF packing, loosen packing flange nut 1/4 turn (90_ of rotation).
The "target load" of 85% compression has now been reached.
Refer to the appropriate valve and actuator instruction manuals when connecting the valve to the actuator. Under
normal conditions, the packing nut should not require retightening.
2. However, when servicing, if the springs do not remain at the target load of 85% compression, retighten the packing
box nut according to step 1 above.
Other Considerations
When repacking a valve with ENVIRO-SEAL packing that has been in service, check the condition of the packing bore
after the packing has been removed. A good guideline to use in checking the condition of the packing bore is the
20/20 rule. If less than 20% of the surface area of the bore is pitted and if there are no pits deeper than 0.020 inch, then
the packing should work as designed. This does not need to be an exact measurement; visual inspection is adequate. If
the packing bore does not meet these criteria, the unit should be replaced.
easy-e Trim Cartridge
October 2021
7
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