Grain Systems PNEG-526 - Manual (Page 178)

Servicing – General Instructions
Same general instructions as listed on Page 6.
To Service Valve (15)
1. Remove bolts 38 and remove bottom cap 37.
2. Remove retaining ring 16a. Use Truarc 0400 pliers, Invensys Part
No. 1190647.
3. Remove both halves of valve holder 16b.
4. Remove valve 15, and wing 15a or spacer (wave washer 14 will
probably also come off...do not lose it).
– To reassemble, replace parts in reverse sequence.
To Service Main Diaphragm (11d)
1. Remove top cap 1.
2. Release adjustment 3 (count the turns of adjustment 3 and use for
returning the adjustment to this setting during reassembly).
3. Remove bolts 10 and housing 5 (3" and 4" 121-16 only).
4. Remove spring 9.
5. Remove bolts 22 and upper case 21.
6. Rotate diaphragm assembly 11 counterclockwise (this unscrews
11h from 12d) and remove.
7. To disassemble diaphragm assembly, remove nut 11a. Carefully
note location and position of all parts to be certain of correct reas-
sembly. Abrasive side of emery cloth washers face against
diaphragm.
– To reassemble, replace parts in reverse sequence.
Make the screwed connection between 11h and 12d loose by
approximately 1 /
2
turn. To do this, carefully rotate diaphragm
assembly 11 clockwise until this screwed connection bottoms (do
not jam it together). Then, back-off diaphragm assembly 11 counter-
clockwise approximately 1 /
2
turn...this is very important...the 11h to
12d screwed connection must not be tight.
To Service Orifice (19)
1. Remove valve 15 per section “To Service Valve (15)”.
2. Remove seal diaphragm assembly 12 per step 2 under “To Service
Seal Diaphragm (12b)”.
3. Remove retaining ring 19a. Use Truarc 0600 pliers, Invensys Part
No. 1190648.
4. Remove ring 33 and orifice 19 through top opening.
– To reassemble, replace parts in reverse sequence.
(On reassembly, be sure that 19a is fully seated in its groove. Also,
beveled edge of 19a faces downward toward bottom cap 37).
To Service Seal Diaphragm (12b)
1. Remove valve 15 per section “To Service Valve (15)”.
2. Remove bolts 29 and upper case assembly. Then remove seal
diaphragm assembly 12.
3. To disassemble 12, unscrew piston 12a from stem 12d. Use a
spanner wrench in notch in skirt of piston (this can also be done by
inserting a standard 7 /
32
" Allen wrench in the notch).
– To reassemble, replace parts in reverse sequence.
Make certain that fabric side of seal diaphragm 12b faces upward
and “rubber” side faces downward toward body.
Do not pinch loop in seal diaphragm 12b between ring 33 and cen-
terpiece 27. Also, rounded edge of 33 faces upward toward seal
diaphragm 12b.
Make the screwed connection between 11h and 12d loose by
approximately 1 /
2
turn. To do this, carefully rotate seal diaphragm
assembly 12 clockwise until this screwed connection bottoms (do
not jam it together). Then, back-off seal diaphragm assembly 12
counterclockwise approximately 1 /
2
turn...this is very important...the
11h to 12d screwed connection must not be tight.
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