Jordan Valve Mark 5108 Series Back Pressure Regulator - Manual

Main Valve
(Mark 5108 & Mark 6127)
Installation,
Operating and
Maintenance
Instructions
I
nstallatIon
In order to insure safe, accurate and efficient
operation of the Jordan piloted regulator, the following
list of checkpoints and procedures should be
followed when installing the valve.
1. Make a careful visual inspection of the valve to
insure that there has been no damage to the
external piping, fittings or controls. Check that all
fittings are tight.
2. Thoroughly flush all interconnecting piping of
chips, scale and foreign matter prior to mounting
the valve.
3. Install the valve in the line according to the flow
arrow on the inlet flange. The arrow should point
downstream.
4. Allow sufficient room around the valve for ease of
adjustment and maintenance service.
G
eneral
D
escrIptIon
The main valve of the Mark 5108 and Mark 6127 is a
hydraulically-operated, diaphragm-actuated valve. It is
available in either a globe or angle configuration. The
diaphragm is nylon-fabric bonded with synthetic rubber
and forms a sealed chamber in the upper portion of the
valve, separating operating pressure from line pressure.
An elastomeric seat disc forms a tight seal with the valve
seat when pressure is applied above the diaphragm.
F
unctIonal
D
escrIptIon
Because this valve is a hydraulically operated valve, it
requires a minimum line pressure of approximately 5
psig in order to function. The valve functions on a simple
principle of pressure differential. The line pressure at the
inlet of the valve is bypassed through the pilot control
piping to the diaphragm chamber of the valve. This
pressure, together with the valve spring, works against
the pressure under the valve seat. Because the effective
area of the diaphragm is greater than that of the seat,
the valve is held tightly closed. As the controlling pilot(s)
allow the pressure to bleed off the diaphragm chamber,
the two opposing pressures begin to balance and the
valve will begin to open. The valve can be used to
perform a simple on-off function, or with the proper pilot
system, a modulating, or regulating function.
In cases where the line fluid is unusually dirty, or
is otherwise unsuitable for operating he valve, an
independent operating pressure source may be
employed. The pressure available from such a source
must be equal to, or greater than, line pressure.
-1-
M
ark
5108 & 6127 S
erieS
M
ain
V
alVe