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SeeFlo® 7 Meter / Mix / Dispense System meets
Critical Mix Ratios in abrasive Urethane Application
A leading US Filter Manufacturer
based in New York, manufactures an extensive range of replacement filter
assemblies for the spas, pools and Jacuzzi® whirlpools markets.
 The right tool for a task not only gets the
job done - it gets it done better and faster. It is no different with
dispensing equipment. The right dispense system can turn ideas into product and
productivity into profit.
Dispensing two-part polyurethane's is a key
element in Pleatco's production. Pleatco, located in New York, is a leading
manufacturer of replacement water filters for use in spas, pools and
Jacuzzi® whirlpools. Pleatco's replacement cartridges are available for
over 60 different manufacturers. All in all, there are over 200 different
models.
Making filters to meet demanding
specifications, yet cost effectively, is a manufacturing necessity. Pleatco
relies on its chief operating officer, Lenny Kott, to produce top quality,
uniquely designed filters to satisfy demanding manufacturing requirements while
controlling production costs. Kott is in charge of production and filter
design. His experience has positioned Pleatco at the forefront of spa filter
manufacturers.
In production, reliability is a must. You
can't make a filter if the dispense machine is down. To Kott, the
SeeFlo® 7 meter / mix / dispense system
from Sealant Equipment & Engineering is a "beautiful thing" because
its reliability, coupled with its flexibility, gives him the tool to make the
Pleatco filters.
The
Polyurethane Formulations
The different polyurethane formulations
that Pleatco uses to produce end caps for filters are chlorine-resistant and
colour-coded. The Polyurethane curing systems require different mix ratios (
6:1 to 2:1 ) to produce end caps with different physical properties. The
polyurethane ratio is changed to match the filter properties and to maximise
curability.
The
Manufacturing Process
The filters are made in a variety of sizes
from a pleated media - a thick, polyester-type fabric. At each end of the
pleated material is the base. The base fixes the pleating in position and
allows the unit to become a filter. While other filters have a separate metal
or plastic end cap into which the polyurethane and pleating are placed, Pleatco
moulds the entire end cap from polyurethane. The polymer seals each end cap and
becomes a permanent part of the filter. Pleatco also includes several other
user-friendly features into the moulded end cap.
Filter
Design and Manufacturing
For some models, Pleatco's patented design
incorporates threads and a handle into the end cap, making it easy for the
customer to replace the reusable core or to attach the filter to their water
purification system. Some of the filters include disinfectants in the cartridge
core.
To manufacture the filter, the mixed
urethane is dispensed into a mould and the pleating is inserted. The uncured
urethane wicks up the pleating as it hardens to form a tight seal to all parts
of the pleating. After a short cure time, the hardened end cap is formed from
the urethane, sealing the end of the filter while providing support for the
pleating. A release agent allows the assembly to be quickly separated from the
mould.
Processing the urethane with a short cure
time to achieve the rugged properties of the end cap is the result of years of
research and work by Kott, a self-taught expert on dispensing urethanes.
"Different filters demand different urethanes," he notes. "To achieve
various degrees of hardness, you use different mix ratios, And the filters have
a complex design," he says, referring to Pleatco's patent on the filter.
The precisely mixed urethane allows Pleatco to mould the versatile and unique
end caps.
The
Dispensing Equipment
Pleatco exclusively uses
SeeFlo®
7
systems to meter, mix
and dispense the urethane formulations. "One of the beautiful things about
the machine," says Kott, "is its flexibility. I bought the machine to
process entirely different ratios. But since we no longer use that formulation,
all we had to do to retool was change the position of the isocyanate volumetric
cylinder."
High
Volume Use
The dispense systems earn their keep since
Pleatco manufacturers thousands of filters. With two shifts a day during the
peak season, the two
SeeFlo®
7
systems in production provide around-the-clock reliability. In terms
of volume, Pleatco estimates it uses over 2000kg of polyurethane each
week.
Easy
Ratio Adjustment
Going from one ratio to another is an easy
manual adjustment. To change the mix ratio, one of the metering cylinders is
simply repositioned and locked in position. With a couple of checks to verify
the mix ratio, the system is ready to begin dispensing a different
formulation.
Kott says, "Using these machines, I can
run six or seven different formulations without having to purchase a new
machine. This means the least amount of capital outlay without having to go to
the expense of buying new machines."
Different Shot Sizes
Different filters require different amounts
of mixed polyurethane. In order to remain consistent, controls on Pleatco's
SeeFlo® 7 units permit them to
dispense exactly the same amount - or shot -of mixed material each time the
system is actuated. Changing the shot size is another simple
adjustment.
Because all changes are manual (locked and
physical hard stops), there is no need to tweak a drive motor, check a digital
readout or make speed / motor compensations for wear. The position of the
metering pump determines the ratio, and it is consistent and precise. The
system's off-line ratio check verifies the mix ratio. The ratio check can be
done at any time without interrupting production.
Past
Experience
The SeeFlo® 7 was not Pleatco's first
dispensing system. Problems with prior equipment limited production and
required lengthy downtime in order to change ratios. That, coupled with the
abrasive nature of the filled urethanes,
meant considerable maintenance and flexibility. Pleatco's first dispense
systems were single-acting. "That," says Kott, "limits production.
The double-acting cylinders of the SeeFlo®
7 eliminates a reload pause between one end cap and the next.
With the SeeFlo® 7, dispensing
is continuous. You can move from one part to another as quickly as you can
dispense."
Exact
Mix Ratios
"The SeeFlo® 7 system precisely dispenses
the two components I need to make a polyurethane end cap to the filter,"
Kott explains.
"In my case, it's critical that the mix is to the exact
ratio or it's no good. The SeeFlo® 7
also provides me with good cures from low (volume) to large shot
sizes. Generally, with variable ratio you're not able to do this, but I can
with this piece of equipment."
Dispensing is flexible. It can be used for
either large or small filters because the SeeFlo® 7 is a double-acting system -
there is no reload necessary. With production of filters increasing each day,
Pleatco would have needed several of the single-acting systems to meet
production.
Maintenance and down time are day-to-day
issues with a filled material. Wear on internal component's results in a poor
mix ratio that can turn the filters into scrap. With the metering pump design
of the SeeFlo® 7, the exact mix
ratio is assured. The hardened internal components minimise the wear from a
filled formulation. The meter cylinder includes dual sets of multiple
adjustable packing, thereby reducing the abrasive effect of filled material.
This, in turn, translates into higher productivity.
Another positive feature of the
SeeFlo® 7 is that it is not
affected by temperature. If the viscosity of the urethane rises in the cooler
months, the system will still dispense the same exact volume. The positive
displacement and balanced design of the metering cylinders assure accuracy all
the time.
System
Versatility
The system's versatility extends even
further. By using different metering pumps, you can easily hit ratios from 1:1
up to 56:1 by volume with no other changes, just the pump. With over seven
different positive-displacement pumps, the SeeFlo® 7 is capable of handling an
extremely broad range of volumetric mix ratios and viscosity's.
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