Emerson Anderson Greenwood 93 Series, Инструкция по установке и обслуживанию

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ANDERSON GREENWOOD SERIES 93T PILOT OPERATED SAFETY RELIEF VALVES
INSTALLATION AND MAINTENANCE INSTRUCTIONS
PARTS LIST
Item Description
1 Cap
2 Pressure adj. bolt
3 Bonnet
4 Spring
5 Sense plate
6 Upper case
7 Spacer ring
8 Lower case
9 Boost spacer
10 Spindle diaphragm
12 Nozzle
13 Seat
14 Body
15 Vent
17 Check plate
18 Pilot diaphragm
19 Boost plate
20 Sense spacer
21 Blowdown needle
22 Seal, body
23 Filter
24 Seat retainer
25 Retainer ring
26 Bonnet gasket
27 Bushing seal
28 Blowdown seal
29 Diaphragm gaskets
30 Diaphragm gasket
31 Boost tube seal
FIGURE 3
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4 PILOT ADJUSTMENT
4.1 General
Two adjustments are provided; one for varying
the pressure at which the pilot opens and
one for varying the pressure at which the
pilot closes. The first adjustment controls the
“set” or “popping” pressure, the second the
“reseat” or “blowdown” pressure. To adjust set
pressure, a test set-up similar to that shown in
Figure 4 should be used.
4.2 Set pressure
This adjustment is obtained by turning the
pressure adjusting bolt, clockwise (in) to
increase set pressure and counter- clockwise
(out) to decrease set pressure.
4.3 Reseat pressure
This adjustment is obtained by turning the
blowdown needle adjusting screw, clockwise
(in) to increase blowdown, counter-clockwise
(out) to decrease blowdown. A small interaction
between set pressure and reseat pressure
adjustments will occur, therefore it may be
necessary to readjust the set pressure after
setting reseat pressure.
Note: if the blowdown adjusting screw has been
moved or turned to either extreme, positioning
it midway will aid in obtaining the corrected
blowdown. There are approximately 7 to 8 turns
to obtain full travel of the adjustment. Midway
from either end should produce a blowdown
for “snap action”. For “modulating pilot action”,
back the adjustment screw out (counter-
clockwise) to obtain the adjustment limits given
in paragraph 4.5.
4.4 Range of adjustment
All Pilots can be adjusted ± 10% beyond the
nameplate setting.