Product Description; Principle Of Operation - Emerson 63EG Instruction Manual

TYPE PILOT TYPE
6358
6358B
63EG
6358EB
6358EBH
1098-63EGR 6358B
1. Set pressure plus buildup should not exceed maximum differential pressure of 400 psig / 27.6 bar.

Product Description

Types 63EG and 1098-63EGR pilot-operated pressure
relief valves may be used for both liquid and gas
service. The Type 63EG is also suitable for throttling
backpressure or bypass applications. The main valves
in both constructions use a quick-change trim package
for fast maintenance.
Pilot Descriptions
The following pilot configurations are available
for the Type 63EG or 1098-63EGR relief valve or
backpressure regulator.
Relief Valve
For relief valve application use a Type 6358B, 6358EB
or 6358EBH relief pilot. The pilot bleeds constantly
while the relief valve is in operation. The pilot does
not bleed when inlet pressure is below set pressure.
The pilot exhaust can be connected directly to the
main valve exhaust pipe if the pilot connection and
the exhaust pipe are designed to prevent significant
backpressure buildup during full-flow conditions.
Type 6358B—Set pressure range from 10 to
125 psig / 0.69 to 8.62 bar in two ranges. This pilot is
available with a high, medium or low-gain restriction.
Type 6358EB—Set pressure range of 85 to 350 psig /
5.86 to 24.1 bar in three ranges. This pilot is available
with a high or low-gain restriction.
Type 6358EBH—Set pressure range of 250 to
400 psig / 17.2 to 27.6 bar in two ranges. This pilot is
available with a high or low-gain restriction.
Types 63EG and 1098-63EGR
Table 1. Relief Set Pressure and Backpressure Control Ranges
RELIEF SET
PRESSURE RANGE
(1)
psig bar
10 to 40 0.69 to 2.8
35 to 125 2.4 to 8.6
10 to 30 0.69 to 2.1
30 to 60 2.1 to 4.1
60 to 125 4.1 to 8.6
85 to 140 5.9 to 9.6
130 to 200 9.0 to 13.8
180 to 350 12.4 to 24.1
250 to 400 17.2 to 27.6
3 to 18 0.21 to 1.2
15 to 40 1.0 to 2.8
35 to 65 2.4 to 4.5
SPRING PART SPRING
NUMBER COLOR
1E392527022 Yellow
1K748527202 Red
1B788327022 Silver
1B788427022 Blue
1K748527202 Red
17B1261X012 Green
17B1263X012 Blue
17B1264X012 Red
17B1263X012 Blue
1B986027212 Green
1E392527022 Yellow
1K748527202 Red
Backpressure Regulator
The Type 6358 is a low bleed pilot, so it only exhausts
while it is repositioning the main valve. There is no
constant bleed with this construction which is useful for
backpressure applications where minimizing emissions
is important and the pilot exhaust can not be piped
to the downstream piping. This also minimizes dirt
buildup in the pilot. The Type 6358 has a set pressure
range of 10 to 125 psig / 0.69 to 8.62 bar in two
ranges. The Types 6358B, 6358EB and 6358EBH
relief pilots can also be used in backpressure
applications but they will exhaust any time inlet
pressure is above setpoint.

Principle of Operation

A pressure relief valve is a throttling pressure control
device that opens and closes to ensure the upstream
pressure does not rise above a predetermined
pressure. A backpressure regulator is a device that
controls and responds to changes in the upstream
pressure. It functions the same as a relief valve in that
it opens on increasing upstream pressure.
The Types 63EG and 1098-63EGR relief valves are
not ASME safety relief valves.
Type 63EG
Relief Valve
As long as the inlet pressure is below the set pressure,
the Type 6358B, 6358EB or 6358EBH pilot control
spring keeps the pilot valve plug closed. Inlet pressure
passes through the pilot restriction and through the
hollow passage of the valve plug then registers as
SPRING WIRE SPRING FREE
DIAMETER LENGTH
In. mm In. mm
0.148 3.76 2.00 50.8
0.187 4.75 2.19 55.6
0.142 3.61 2.13 54.1
0.182 4.62 1.94 49.3
0.187 4.75 2.19 55.6
0.225 5.72 3.70 94.0
0.262 6.65 3.85 97.8
0.294 7.47 4.22 107
0.262 6.65 3.85 97.8
0.120 3.05 2.12 53.8
0.148 3.76 2.00 50.8
0.187 4.75 2.19 55.6
3