Type 99
10
On reassembly of the regulator, it is recommended 
that a pipe thread sealant be applied to pressure 
connections and ttings as indicated in Figures 7 
and 9 and lubricant be applied to sliding and bearing 
surfaces as indicated in Figures 7 and 9, and that an 
anti-seize compound be applied to adjusting screw 
threads and other areas indicated in Figures 9 and 11.
Actuator and Standard P590 Series Filter
This procedure is to be performed if changing the main 
spring and spring seat for those of a different range, 
or if inspecting, cleaning or replacing any other parts. 
Unless otherwise indicated, part key numbers for a 
Type 99 regulator with low or high-pressure pilot and 
disk or O-ring seat are referenced in Figures 9 through 
15, part key numbers unique to the 1000 psig / 69.0 bar 
maximum inlet regulator are referenced in Figure 17 and 
part key numbers for a Type 61HP (extra high pressure) 
pilot are referenced in Figure 18.
1.  Access to all internal actuator parts can be gained 
without removing the main valve body from the 
line. Disconnect the loading tubing from the 
upper casing.
CAUTION
If the regulator has an indicator 
assembly, perform the following step 
carefully to avoid bending the travel 
indicator stem (key 103, Figure 6).
Note
The O-rings and gaskets (keys 111 and 
108, Figure 6) in the indicator assembly 
are static seals and need not be 
disturbed, unless they are leaking.
2.  Remove the four cap screws (key 58, Figure 9) and 
lift off the spring case (key 1). Remove the travel 
indicator stem, if any, by unscrewing the indicator 
stem adaptor (key 101, Figure 6).
3.  Remove the main spring seat (key 2, Figure 9) 
and main spring (key 3).
4.  Remove the 12 cap screws (key 12, Figure 9) and 
hex nuts (key 13), and lift off the upper casing.
5.  Remove the diaphragm (key 11, Figure 9) and 
diaphragm plate (key 10) by tipping it so that the 
lever (key 9) slips out of the pusher post (key 8).
6.  Separate the diaphragm (key 11, Figure 9) and 
diaphragm plate (key 10) by unscrewing the 
diaphragm rod (key 4) from the pusher post (key 8). 
Inspect the diaphragm (key 11) and pusher post 
gasket (key 7). Either part must be replaced if it is 
damaged or no longer pliable.
7.  If the unit has a stem seal O-ring (key 64, Figure 7 
or 17), this O-ring may be replaced by removing 
the retaining ring or cotter pin (key 28, Figure 9) 
and disconnecting the lever (key 9) from the valve 
carrier (key 26, Figure 9 or 17), removing the union 
nut (key 14, Figure 9), disconnecting the pilot supply 
tubing (key 24, Figure 9 or 17), and sliding the lower 
casing (key 29) away from the valve body (key 17, 
Figure 9), with a disk or O-ring seat, the valve carrier 
must be pulled out of the lower casing (key 29, 
Figure 9 or 17) to gain access to the O-ring. Another 
O-ring, held captive by the pressed-in bushing, is 
part of the lower casing assembly on a stem seal unit 
and normally does not require replacement.
8.  If clogging is suspected in the upstream regulator 
passages, disconnect the pilot supply tubing 
(key 24, Figure 9 or 17), remove the lter 
assembly (key 75, Figure 9), and blow through it 
to check for lter clogging. If necessary, to clean 
or replace lter parts in a standard P590 Series 
lter assembly, remove the following as shown 
in Figure 16: lter body (key 1), machine screw 
(key 4), spring washer (key 6), gasket (key 7), 
washers (key 5) and lter element (key 2). Upon 
reassembly, one of the two washers (key 5) must 
go between the lter element (key 2) and lter 
head (key 3) and the other must go between the 
lter element (key 2) and gasket (key 7).
9.   If the lower casing (key 29, Figure 9) was 
removed, install a new body gasket (key 16) and, 
with a disk or O-ring seat, slide the valve carrier 
(key 26) into the casing (key 29). Then slide 
the entire assembly into the valve body (disk 
or O-ring seat) and secure with the union nut 
(key 14). Secure the lever (key 9) to the valve 
carrier (key 26) with the retaining ring or cotter 
pin (key 28).
10.  Loosely reassemble the diaphragm (key 11, 
Figure 9) and diaphragm plate (key 10) so that 
the bolt holes (key 11) and loading connection 
hole in the diaphragm can be properly aligned 
with the corresponding holes in the lower casing 
(key 29) when the lever (key 9) is tted properly 
into the pusher post assembly (key 8). When this 
orientation is made, install the collar (key 6) and 
tighten the diaphragm rod (key 4) into the pusher 
post (key 8).
11.  In order for the regulator to operate properly, the 
assembled collar (key 6), diaphragm (key 11),