To
obtain its ISO 9000 Certification, State Chemical — a division of State
Industrial Products — replaced its deteriorating batch control systems
with Easy LINK™ solutions consisting of
Burkert Type 8035 inline flow transmitters with digital display, direct-linked
to Burkert Type 2000 Y-pattern valves for precision ON/OFF control.
Located
in Cleveland, Ohio, State Chemical now automatically controls all bulk and
mixed chemical transfers by using the programming capabilities of Type 8035 for
automatic or manually entered batch volumes. This cost effective approach saves
material by reducing the plant’s overfill rate from more than 5% to less than
1%, and reduces human interaction with chemicals during the transfer process,
offering a system payout in two months.
Inside
the 30,000-square-foot plant, operators turn out numerous chemical batches per
day. State Chemical manufactures several thousand industrial cleaning products
including solvents, hand soaps, floor waxes and disinfectants. All finished
goods are water-based and range from highly corrosive, acidic products with a
pH of 0.4, to boiler water treatments which are very basic, and may have a pH
of 13.
Depending
upon which of approximately 300 batch recipes are being made, the compounding
process takes place in a 250- to 3,700-gallon stainless steel compounding tank.
First softened water, then raw chemicals are dispensed in preset quantities and
mixed. Following quality control approval, each batch is filled into finished
goods which range from pint and gallon bottles to bulk pails and drums.
Until
recently, the plant had been getting by with outdated equipment and technology,
according to Tim Gale, State Chemical production engineer.
“We
determined that new process control equipment would have a significant impact
on our product quality. To become ISO 9000 certified, we had to have equipment
that can be calibrated. The positive displacement meters we had been using for
10 to 15 years had become so inaccurate that they could no longer be calibrated,”
Gale explained.
“That
meant we had to manually measure the level of fluid in the tank to determine
how much was actually dispensed. We were losing a lot of fluid so we were
adding more than was necessary. The old valves leaked and didn’t always stop, causing
a lot of spilled product,” he said.
The
decision to go with a Burkert fluid control solution was based on State
Chemical’s success with the Burkert Type 8035 inline digital flow transmitter
for process water dispensing at another site.
So
with ISO 9000 certification as the goal, Gale contacted his Burkert
distributor, HLT Inc. in Parma, Ohio. After several engineering meetings, he
and Mike Coughlin, of HLT agreed on a solution utilizing Burkert Type 8035
inline batch controllers with Burkert Type 2000 Y-pattern valves for controlled
volumes. Four wall-mounted transmitter/valve combinations and several remote
transmitters are used for solvent and process water dispensing. Another flow
transmitter and valve are mounted on a portable transfer unit supplied by HLT
for controlled filling of finished goods.
The
control process is the same for each batch. A Type 8035 batch controller,
consisting of an electronic module with brass fitting, meters the flow of
softened process water in 2-in. lines into the mixing vessel. The quick,
quarter-turn interface between the fitting and sensor facilitated the upgrade
without the need for additional cables or plugs.
Similarly,
solvents are metered in precise amounts from 4,000-gallon underground storage
tanks, using Type 8035 with PVDF fittings. Each transmitter is programmed to
deliver a particular material via a Type 2000 valve, directly connected to the
sensor.
Equipped
with a large LCD digital readout, the Type 8035 displays both flow rate and
volume with up to seven different programmable batches. TEACH-IN and Test
Simulation functions allow setup without actually operating the flow system,
features critical to State Chemical’s ability to meet the demands for
calibration under ISO 9000. The plant calibrates the Burkert Type 8035 flow
transmitters on a quarterly basis, documents the calibration using a
calibration records database and tracks its yields, for total quality control.
Type
8035 has an open-cell, in-line rotor sensor built into the body with ceramic bearings.
When liquid flows through the line, the in-line rotor rotates, inducing a
frequency in the transducer proportional to the flow. Using standard relay
output, the flow transmitters are linked directly to Burkert Type 2000
Y-pattern valves, creating individual ON/OFF control loops that automatically
add the proper materials to the batch in the right amounts.
The
Type 2000 valves feature two sets of self-compensating PTFE seals to keep all
process materials from the actuator mechanism. Positive valve sealing is
assured through the use of an articulated seat, also made of PTFE. Like the
flow transmitter, the Type 2000 also is easy to install. Its compact actuator
lets these valves fit in tight spaces never considered possible with
traditional ball valves. Installation is made simple because the valve’s
pneumatic inlet ports and pilot valve can be rotated 360° around its
circumference.
State
Chemical’s portable unit is used for mixed chemical transfer and filling. It
contains a diaphragm pump and pulsation dampener, a Burkert Type 8035 batch
controller and Type 2000 valve. Type 8035 automatically dispenses the correct
amount of filled product into the container and then closes the valve.
The
new system lets operators be more productive. “Formerly, the operator couldn’t
do anything but stand there and watch the drum fill, and then he had to go
around and label the drums. Now he can label the drum while it fills, paying no
attention to the filler whatsoever,” Gale explained.
Moreover,
filling 5-gallon pails used to be stressful on the operators’ backs, requiring
them to remain bent over while the pail filled. Now they just insert the hose
and the system starts and stops automatically.
Following
ISO 9000 Certification of both its Cleveland and Tulsa, Oklahoma plants, State
Chemical is considering adding Burkert steam valves for temperature control.
According to Gale, the greatest benefit would be the elimination of scrap and
rework because the mixing tank has been overheated or the wrong material added
to the chemical batch.
