Instruction Manual

Instruction Manual
D100390X012
ED Valve
October 2014
8
3. Loosen the packing flange nuts (key 5, figure 18) so that the packing is not tight on the valve stem. Remove any
travel indicator parts and stem locknuts from the valve stem threads.
WARNING
To avoid personal injury or property damage caused by uncontrolled movement of the bonnet, loosen the bonnet by
following the instructions in the next step. Do not remove a stuck bonnet by pulling on it with equipment that can stretch
or store energy in any other manner. The sudden release of stored energy can cause uncontrolled movement of the bonnet.
Note
The following step also provides additional assurance that the valve body fluid pressure has been relieved.
CAUTION
Avoid damaging the seating surface caused by the valve plug and stem assembly dropping from the bonnet (key 1, figure
18) after being lifted part way out. When lifting the bonnet, temporarily install a valve stem locknut on the valve stem. This
locknut will prevent the valve plug and stem assembly from dropping out of the bonnet.
If the cage starts to lift with the bonnet, tap it with a plastic mallet, or other soft material, to be sure it stays in the valve.
4. Hex nuts (key 16, figure 19, 20, or 21) or cap screws (not shown) attach the bonnet (key 1, figure 18) to the valve
body (key 1, figure 19, 20, or 21). Loosen these nuts or cap screws approximately 3 mm (1/8 inch). Then loosen the
body-to-bonnet gasketed joint by either rocking the bonnet or prying between the bonnet and valv e. Work the
prying tool around the bonnet until the bonnet loosens. If no fluid leaks from the joint, remove the nuts or cap
screws completely and carefully lift the bonnet off the valve.
5. Remove the locknut and separate the valve plug and stem from the bonnet. Set the parts on a protective surface to
prevent damage to gasket or seating surfaces.
6. Remove the bonnet gasket (key 10, figure 19, 20, or 21) and cover the opening in the valve to protect the gasket
surface and prevent foreign material from getting into the valve body cavity.
7. Remove the packing flange nuts, packing flange, upper wiper, and packing follower (keys 5, 3, 12, and 13, figure
18). Carefully push out all the remaining packing parts from the valve side of the bonnet using a rounded rod or
other tool that will not scratch the packing box wall. Clean the packing box and the metal packing parts.
8. Inspect the valve stem threads and packing box surfaces for any sharp edges which might cut the packing.
Scratches or burrs could cause packing box leakage or damage to the new packing. If the surface condition cannot
be improved by light sanding, replace the damaged parts by following the appropriate steps in the Trim
Maintenance procedure.
9. Remove the cover protecting the valve body cavity and install a new bonnet gasket (key 10, figure 19 through 21),
making sure the gasket seating surfaces are clean and smooth. Place the valve plug and stem into the valve body,
making sure it is properly centered on the seat ring. Then slide the bonnet over the stem and onto the stud bolts
(key 16, figure 19, 20, or 21) or onto the valve body cavity if cap s crews (not shown) will be used instead.