Type 99
8. Four machine screws (key 130) hold both yoke
caps (keys 37 and 116) to the yoke legs (key 31).
Separate these parts to expose the pilot valve.
9. Unscrew the inlet orifice (key 38) to inspect its
seat, the inlet valve plug (key 117), and valve
spring (key 124).
Note
Make certain that the yoke assembly is square with respect to the cross member of the body casting so that it will not bind on the body.
10. When reassembling, screw in the inlet orifice all
the way and secure the yoke caps to the yoke
legs. Replace two diaphragm plates, the
diaphragms, and inserts, two more diaphragm
plates, the hex nut, and the relief valve assembly.
11. Assemble the control spring and spring seat
into the body and spring case, being careful
that the diaphragms are free of wrinkles and
properly in place, and evenly installing the cap
screws in a crisscross pattern to avoid placing a
strain on the unit. Install the body flange adapter
with seal washers and cap screws. Install a new
gasket and secure the pilot to the lower casing
with eight cap screws. Set the control spring
according to the adjustment information in the
Startup section.
Converting the PilotNote
A complete pilot assembly rather than individual parts may be ordered for the following conversion procedure. When a low pressure pilot is ordered for field conversion of a high pressure pilot or vice versa, the replacement pilot assembly comes complete with a pilot cover (key 132, Figure 9). Remove this cover before installing replacement pilot on the existing regulator. The cover can then be installed on the removed pilot to form a complete Type 61 (low or high pressure) pilot for use elsewhere.
When changing one pilot construction (low pressure, high pressure, or extra high pressure) for another, all parts attached to the lower casing (key 29, Figure 9) may need to be replaced with those appropriate for the desired construction. At the very least, when changing from a
low to high pressure pilot or vice versa, everything below the lower pilot diaphragm (key 40, Figure 9) except the cap screws and the hex nut (keys 47 and 13, Figure 9) will need to be replaced. Actuator and main valve parts may remain unchanged unless a change in service conditions requires a change in seat construction, main spring, or main spring seat. See the Parts List sections for obtaining the appropriate conversion parts.
Main Valve Trim with Disk orThis procedure is to be performed if inspecting, cleaning, or replacing trim parts. Part key numbers for a Type 99 regulator with disk or
Note
All trim maintenance may be performed with the valve body (key 17, Figure 9 or 11) in the line and with the elbow (key 23, Figure 9 or 11), pilot supply tubing (key 24, Figure 9 or 11), and pilot supply regulator (key 155, Figure 11, if used) attached to the valve body unless the valve body itself will be replaced.
1. Disconnect the pilot supply tubing and downstream
control line.
2. Loosen the union nut (key 14, Figure 9) and
remove the lower casing (key 29, Figure 9) with
the cap screw (key 22, Figure 9) or disk and
holder assembly (key 18, Figure 11) on
disassembly or reassembly. A
may be used to remove the orifice.
3. Access to the disk or
be gained by removing the cap screw and retainer
(key 21, Figure 9), while on the 1000 psig
(69,0 bar) maximum inlet regulator the entire
disk and holder assembly is removed as a unit.
If necessary, the holder (key 18, Figure 9 or 11) or
adapter (key 157, Figure 11) can be removed by
taking out the cotter pin (key 25, Figure 9 or 11).
4. Install a new body gasket (key 16, Figure 9) and
a new disk,
as necessary. Then slide the entire assembly into
the valve body and secure with the union nut.
5. Connect the pilot supply tubing and downstream
control line, then refer to the Startup section for
putting the regulator into operation.
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