April 2022
Installation, Operation and Maintenance Manual
E-90090007 Rev. 0
24
Section 7: Maintenance
Maintenance
7.4
Reassembly
NOTE:
Refer to Section 7.2 and reassemble the unit in reverse order. Make sure to reassemble
parts in the same orientation as before. Pay extra attention to the following items below.
Make sure all operator component parts are cleaned and lubricated (if required) prior to
installing seals.
1.
Use only new replacement seals (available as an operator-specific kit from
Emerson Process Management).
2.
Lubricate seals, rods, and cylinder bore with a generous amount of
recommended grease.
3.
Lubricate bushing and guides with a light coating of recommended grease.
4.
Apply recommended grease/lubricant to the sealing surfaces and around the
cylinder plate bore when installing the drive rod (1) and piston (11) onto the
pedestal assembly (140). Do not rub the bore on cylinder plate.
5.
If piston (11) and drive rod (1) are disassembled, (which means piston center seal
(52) will be replaced) make sure to apply recommended grease prior to attaching
the drive rod (1) to the piston (11). Apply thread locking adhesive (for example,
Loctite) to thread(s) of hex nut or jackscrews.
a.
Fix the drive rod by securely clamping the flat surface on its bottom
using some mechanical means if using a hex nut. Refer to Table 4 for
torque per specifications.
Table 4.
Specification of Piston Hex Nut Tightening Torque
Piston Hex Nut Size
(-)
Tightening Torque
(lbf.ft)
1/2 NC
50
5/8 NC
90
3/4 NC
160
7/8 NC
240
1 - 8UN
370
1-1/4 - 8UN
800
1-1/2 - 8UN
1500
1-3/4 - 8UN
2400
