EMERSON ENVIRO Seal PTFE Instruction Manual

EMERSON ENVIRO Seal PTFE

Design A, E, EH, HP, YD, and YS ENVIRO-SEAL PTFE Packing for 3/8-inch and 1/2-inch Stem Sizes

Use these instructions to install ENVIRO‐SEAL packing in valves that have standard packing or when inspecting or replacing ENVIRO‐SEAL packing. For additional information, see Fisher™ ENVIRO‐SEAL Packing Systems for Sliding-Stem Valves Instruction Manual ().

  WARNING

Avoid personal injury or property damage from sudden release of process pressure or uncontrolled movement of parts. Before performing any maintenance operations:Disconnect any operating lines providing air pressure, electric power, or a control signal to the actuator. Be sure the actuator cannot suddenly open or close the valve.Use bypass valves or completely shut off the process to isolate the valve from process pressure. Relieve process pressure from both sides of the valve. Drain the process media from both sides of the valve.Vent the pneumatic actuator loading pressure and relieve any actuator spring pre compression. If a spring-return actuator is used, be sure the actuator is resting on its travel stop before disconnecting the stem connector.Use lock‐out procedures to be sure that the above measures stay in effect while you work on the equipment.

If you are installing the system in a valve that is still connected to an actuator, remove the actuator from the valve to provide sufficient space to install the packing assembly. Refer to the appropriate valve and actuator instruction manuals to remove the actuator.

1. Carefully remove the old packing parts from the packing box. The surface condition of the valve stem and the packing box wall is critical in obtaining a good seal. If the valve stem needs to be replaced, or any other valve part, refer to the appropriate valve instruction manual for replacement procedures. Complete all valve maintenance before installing the ENVIRO‐SEAL packing system into the bonnet.
2. If a retrofit kit is being installed in place of the original packing, it may be necessary to remove the old studs from the valve because they are too short. Check stud length by installing the packing and the spring pack assembly using the following assembly procedures, and try installing the packing nuts. If the packing nuts will not start on the threads of the studs, it will be necessary to install new studs and nuts from the retrofit kit.NoteEnsure that the packing box parts are assembled in the correct order. Packing parts can not function properly if the Belleville springs or other packing parts are not stacked correctly.
3. Use the drawing provided to ensure that the packing parts are assembled in the correct order. Install the ENVIRO‐SEAL packing parts into the packing box.
4. Install the spring pack assembly (key 217), which includes the attached springs, and packing flange (key 201), on the stem. Install the nuts and hand tighten them.NoteLubrication is required for the packing studs and nuts. Although it is important to properly lubricate the stud threads and internal nut threads, it is also important to properly lubricate the contacting face of the nut.
5. You will obtain maximum benefit from your ENVIRO‐SEAL packing system when you tighten the packing flange nuts and compress the Belleville springs to their “target load.” The target load is the point where the Belleville springs are designed for optimum performance, when they are 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:● Tighten the packing flange nuts alternately and evenly, keeping the packing flange parallel with the valve flange, until the Belleville springs are compressed 100% (or completely flat). Refer to the ENVIRO-SEAL Packing Instruction Manual () for more information.● For PTFE packing, loosen each packing flange nut 1/2 turn (180 degrees rotation). The “target load” of 85% compression has now been reached.
6. Refer to the appropriate valve and actuator instruction manuals when connecting the valve to the actuator. Under normal conditions, the packing nuts should not require re-tightening.

Packing Kits

For additional information concerning the installation of this packing kit, please consult the appropriate product instruction manual.

Stems and packing box constructions that do not meet Emerson stem finish specifications, dimensional tolerances, and design specifications, may adversely alter the performance of this packing kit.

Neither Emerson, Emerson Automation Solutions, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user.

ENVIRO-SEAL and Fisher are marks owned by one of the companies in the Emerson Automation Solutions business unit of Emerson Electric Co. Emerson Automation Solutions, Emerson, and the Emerson logo are trademarks and service marks of Emerson Electric Co. All other marks are the property of their respective owners.

The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are governed by our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications of such products at any time without notice.

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References

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