LowFlow Mark 708SH Series Short Pattern 1/4 - Manual

3170 Wasson Road • Cincinnati, OH 45209 USA
Phone 513-533-5600 • Fax 513-871-0105
[email protected] • www.lowflowvalve.com
I & M Mark 708
Installation & Maintenance Instructions for
Mark 708 & 14M Actuator and Motor Valve
Warning: Jordan LowFlow Control Valves must only be used, installed and repaired in accordance with these
Installation & Maintenance Instructions. Observe all applicable public and company codes and regulations. In
the event of leakage or other malfunction, call a qualified service person; continued operation may cause system
failure or a general hazard. Before servicing any valve, disconnect, shut off, or bypass all pressurized fluid. Before
disassembling a valve, be sure to release all spring tension.
Please read these instructions carefully!
Your Jordan LowFlow Valve product will provide you with
long, trouble-free service if it is correctly installed and
maintained. Spending a few minutes now reading these
instructions can save hours of trouble and downtime
later. When making repairs, use only genuine Jordan
LowFlow Valve parts, available for immediate shipment
from the factory.
Ideal Installation
To control very low flow rates, Mark 708 control 1.
valves are often provided with trims having very
small clearances. To keep this trim functioning
properly, it is essential that the fluid flowing through
the valve be clean.
To protect the valve from grit, scale, thread chips 2.
and other foreign matter, ALL pipelines and piping
components should be blown out and thoroughly
cleaned before the installation process begins.
Shutoff valves, pressure gauges, and by-pass piping 3.
should be installed as indicated in the Installation
Schematic to provide easier adjustment, operation
and testing.
A line strainer should be installed on the inlet side 4.
of the valve to protect it from grit, scale, and other
foreign matter. A 0.033 perforated screen is usually
suitable for this purpose. Line strainers are avail-
able from Jordan Valve.
For best control, 3’ 0” straight sections of pipe 5.
should be installed on either side of the valve.
In preparing threaded pipe connections, care 6.
should be exercised to prevent pipe-sealing com-
pound from getting into pipelines. Pipe sealing
compound should be used sparingly, leaving the
two end threads clean. Jordan uses, and recom-
mends, thread sealer Teflon ribbon.
The flow arrow on the valve body must be pointed 7.
in the direction of the flow. Ideally the valve should
be installed in the highest horizontal line of pip-
ing to provide drainage for inlet and outlet piping,
to prevent water hammer, and to obtain faster re-
sponse.
If possible, install a relief valve downstream from 8.
the valve. Set at 15 psi above the control point of
the valve.
In hot vapor lines, upstream and downstream pip- 9.
ing near the valve should be insulated to minimize
condensation.
Evaluate inlet and outlet pipe friction losses and ve- 10.
locities to decide when smaller outlet piping might
cause excessive back pressure. When required, a
standard tapered expander connected to the outlet
of the valve is recommended.
Where surges are severe, a piping accumulator is 11.
recommended.
On steam control applications, install a steam trap 12.
with sufficient capacity to drain the coil or condens-
er. Be sure to have a good fall to the trap, and no
backpressure. Best control is maintained if the coil
or condenser is kept dry.
Start-Up Procedure
Be sure that the action of the control valve and of 1.
the controller are such that you achieve the desired
results. The action can be changed if needed us-
ing the instructions shown in “Reversing Action”.
Increase in pressure
or temperature must:
And the action of
the valve is:
Then the action of the
controller must be:
Close Valve Air to Close (direct) Direct
Close Valve Air to Open (reverse) Reverse
Open Valve Air to Close (direct) Reverse
Open Valve Air to Open (reverse) Direct
1. Shut off Valve
2. Pipe Union
3. Strainer and Drain Valve
4. Pressure Gauge
5. Mark 708DCV
6. Relief Valve
3
R
6
4
1
5
1
4
2
1
2
1