Fisher EZ easy-e Instruction Manual page 10

EZ Valve
November 2017
3. Hex nuts (key 16, figure 11) attach the bonnet to the valve. 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 valve body. Work the prying tool around the bonnet until the bonnet loosens.
4. Loosen the packing flange nuts (key 5, figure 11) so that the packing is not tight on the valve stem. Remove any
travel indicator parts and stem locknuts from the valve stem threads.
CAUTION
Avoid damaging the seating surface caused by the valve plug and stem assembly dropping from the bonnet 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.
5. Completely remove the cap screws (not shown) or hex nuts (key 16, figure 12) that bolt the bonnet and valve body
together and carefully lift the bonnet off.
6. 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.
7. Remove the bonnet gasket (key 10, figure 12) and cover the opening in the valve to protect the gasket surface and
to prevent foreign material from getting into the valve body cavity.
8. Remove the packing flange nuts, packing flange, upper wiper, and packing follower (keys 5, 3, 12, and 13, figure
11). 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.
9. Inspect the valve stem threads and the 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.
10. Remove the covering protecting the valve cavity and install a new bonnet gasket (key 10, figure 12), making sure
the gasket seating surfaces are clean and smooth. Then slide the bonnet over the stem and onto the stud bolts (key
15, figure 12), or onto the valve cavity if cap screws (not shown) are used instead.
Note
Proper performance of the tightening procedures in step 11 compresses the spiral wound gasket (key 12, figure 12) enough to
both load and seal the seat ring gasket (key 13, figure 12). The tightening procedures also compresses the outer edge of the
bonnet gasket (key 10, figure 12) enough to seal the body‐to‐bonnet joint.
The accepted bolting procedures referred to in step 11 include‐‐but are not limited to‐‐ensuring that bolting threads are clean, and
evenly tightening the cap screws, or the nuts onto the studs, in a crisscross pattern. Because of the boltup characteristics of spiral
wound gaskets, tightening one cap screw or nut may loosen an adjacent cap screw or nut. Repeat the crisscross tightening pattern
several times until each cap screw or nut is tight and the body‐to‐bonnet seal is made. When the operating temperature has been
reached, perform this torquing procedure once again.
Note
Stud(s) and nut(s) should be installed such that the manufacturer's trademark and material grade marking is visible, allowing easy
comparison to the materials selected and documented in the Emerson/Fisher serial card provided with this product.
WARNING
Personal injury or damage to equipment could occur if improper stud and nut materials or parts are used. Do not operate or
assemble this product with stud(s) and nut(s) that are not approved by Emerson/Fisher engineering and/or listed on the
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Instruction Manual
D100401X012