Specifications; Installation - Marshall Excelsior MEGR-198H Instruction Manual

Applications
Superheated Steam
Steam Tracing
Nitrogen Purging
Boiler Feed Water
Process Chemicals
Cooling Water
Test Fixtures
Wash Tanks
Sterilizers/Autoclaves
Fuel and Oil Lines
Pneumatic Supply
Introduction
The MEGR-198H backpressure regulator is a manual, direct
acting, self-operating, spring loaded, large capacity adjustable
relief valve. It monitors upstream pressure and opens to
relieve excess pressure when the upstream pressure increases
above a set point. As a backpressure regulator, the upstream
pressure is monitored and released downstream when the set
point is exceeded. Relief pressure ranges are 15 to 200 PSIG
for the MEGR-198H.
How It Works
The force of the range spring acting against the diaphragm is
opposed by the force of the relief pressure acting against the
opposite side of the diaphragm. Until the force of the relief
pressure overcomes the force of the range spring acting
against the diaphragm, the MEGR-198H main valve will
remain closed. After the relief pressure force overcomes the
force of the range spring acting on the main valve, the main
valve will open pressure from the inlet port and allow it to
flow into the outlet port. Once this pressure decreases beneath
the set point of the range spring, the main valve closes again.
Materials of Construction
Body Iron
Bonnet Iron
Diaphragm Stainless Steel
Valve Plug Stainless Steel with Nitrile
Form #904 Rev A

Specifications

Maximum Inlet
Pressure Ranges
Port Sizes
Orifice Sizes
End Connections
Temperature Range - Nitrile
Approximate Weight
Shutoff Classification

Installation

Qualified personnel should perform installation, operation and
maintenance in accordance with NFPA 54 & 58 and other
local, State and Federal Regulations. The regulator can be
mounted in any position, however the flow through the body
must be in the direction from inlet to outlet (as marked by the
arrow on the body). It is important that the drilled bonnet vent
remain unobstructed at all times. Also make sure to position
the regulator to prevent any contamination, rain and debris
from entering the drilled bonnet vent. Prior to installation,
inspect the regulator and the piping lines for any debris or
contamination. Apply pipe compound to the male pipe
threads prior to installation. After installation, periodically
inspect the regulator for damage, especially after any
overpressure condition.
Warning!
If the MEGR-198H operates beyond the listed
specifications, it may cause damage to the internal parts,
up to and including blowing a hole in the diaphragm.
Please periodically check the drilled bonnet vent to see if
any sort of leakage is occurring. If so, safely remove the
regulator from the line and inspect for damage.
Start-Up and Adjustment
Warning!
The use of pressure gauges to prevent overpressure
conditions, which might cause personal injury or
equipment damage, is highly recommended. Before
starting up the regulator, relieve the downstream pressure
on the diaphragm. Failure to do so may result in personal
injury or equipment damage.
300 PSIG
SEE TABLE 1
3/4" NPT
1" NPT
3/4" NPT-9/16"
1" NPT-9/16"
NPT
-20°F TO 200° F
-29°C TO 93° C
20 lbs (9.1 kg) for 3/4"
NPT
20 lbs (9.1 kg) for 1" NPT
Class VI