Liquid Controls Strainers F-7, FA-7, F-15, F-30 & Steel Series - Manual (Page 4)

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InsTallaTIon and oPeRaTIon
lC strainers overview
WhaT lC sTRaIneRs do
Strainers help to protect meters from serious damage
caused by burrs dislodged from new piping, pipe scale or
foreign material. The strainer’s initial cost is good insurance
against the cost of down time and replacement parts
incurred from a damaged meter. A meter strainer installed
on the inlet side is necessary even when a coarse strainer
on the upstream side of the pump is included in the system.
Strainers are not meant to be used as a system filter but
as limited protection for the meter element itself.
hoW lC sTRaIneRs WoRk
As a liquid product enters the strainer housing from the
supply line, it is routed through the strainer basket. The
strainer basket is a two-ply screen. The inner screen is
made of fine mesh of either 20, 40, 80, 100, or 200 squares
per inch. The outer screen works as a backing. It gives
reinforcement and support to the fine mesh inner screen.
Liquid passes through the strainer and into the inlet of
the meter. Any debris that is larger than the mesh in the
basket is trapped in the basket. THE STRAINER IS NOT
A FILTER, and the size of the mesh in the basket selected
will determine the particle size that can pass through the
strainer. Basket mesh selection is generally based on
maximum fluid viscosity at minimum ambient operating
temperature.
Relieving Internal Pressure
All internal pressure must be relieved to zero pressure before disassembly or inspection of the strainer, vapor eliminator, any
valves in the system, the packing gland, and the front or rear covers.
Relieving Internal Pressure Procedure for lPG and nh
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meters
6. Slowly crack the fitting on top of the differential valve to
relieve product pressure in the system. Product will drain
from the meter system.
7. As product is bleeding from the differential valve, slowly
reopen and close the valve/nozzle on the discharge line.
Repeat this step until the product stops draining from the
differential valve and discharge line valve/nozzle.
8. Leave the discharge line valve/nozzle open while working
on the system.
1. Close the belly valve of the supply tank.
2. Close the valve on the vapor return line.
3. Close the manual valve in the supply line on the inlet side of
the meter. If no manual valve exists on the inlet side, consult
the truck manufacturer for procedures to depressurize the
system.
4. Slowly open the valve/nozzle at the end of the supply line.
5. After product has bled off, close the valve/nozzle at the end
of the supply line.
Serious injury or death from fire or explosion could result in performing maintenance on an
improperly depressurized and evacuated system.
! WaRnInG
feaTURes
LC markets a wide variety of strainers to fit most meters
in terms of capacity, pipe size, working pressure and
metallurgical compatibility.
The design advantages of a liquid Controls strainer
include:
• Strainer baskets with an unusually high open basket area
to pipe area ratio, resulting in minimum restriction of flow
and low pressure loss.
• Choice of 20, 40, 80, 100 or 200 mesh cadmium plated
steel or stainless steel strainer baskets.
• Installation in a variety of positions, that simplify piping.
• Optional 45 accessory elbows for indexing strainer inlet
positions other than right angle flow. Available for 2” F-7
Aluminum strainers only.