Cut-away of heavy duty Vanton
polypropylene centrifugal pump of the
design selected by Hitachi for their
wafer fabrication facility. These pumps
replaced thermoset units, which leaked
and deteriorated under the severe
The front bearing can be pulled back on
sliding bars for easy maintenance and
flexibility to accommodate virtually any
Key driven molded impeller with
investment casting insert to insure
positive drive, provide additional
rigidity to impeller at higher
temperatures and heads, as well as to
prevent damage from reverse rotation.
Pump Choice Supports
Continuous Production at
Deionized water, Hydrochloric acid, Hydrofluoric acid
CHEM-GARD Horizontal Centrifugal Pump
Reprinted from ENGINEER'S DIGEST
FOCUS ON FACILITIES
In addition to an ultra-clean environment, the fabrication of high quality
silicon wafers — submicron integrated circuits — requires dependable
equipment to ensure continuous production. So, you can imagine the
concern when maintenance personnel at Hitachi's wafer fabrication
facility in Irving, Texas, discovered that original pumps were not doing
the job. Some leaked and others failed to keep up with flow
During the production process, high-standard circuits result from a
series of physical and chemical steps. Layer upon layer of micro-thin
material is applied to silicon wafers. The process involves the use of
severely corrosive materials such as hydrochloric acid, hydrofluoric acid
and various caustic solutions.
Almost from the beginning of operations, maintenance personnel
reported that pumps of thermoset plastic on bulk hydrochloric acid
(HCI) storage tanks leaked. HCI is used for regeneration of mixed beds
(deionized water) and pH control of waste water. The source of the
problem was a combination of the pump's design and the materials of
In addition, during the start-up phase, maintenance noted capacity
problems with pumps handling dilute hydrofluoric acid-waste.
Operations were exceeding original design flows; the pumps couldn't
The facility decided to replace the thermoset pumps with heavy-duty
centrifugal polypropylene pumps (Vanton Pump & Equipment Corp.,
Hillside, N.J.) The new pump's design limits fluid contact to plastic
components and, in fluid-contact areas, uses acid-resistant
polyvinylidene fluoride to sheath a stainless-steel shaft.
According to Paul W. LeMarie, Jr., senior facilities engineer, since
installing the new pumps, leakage and capacity problems have
NOTE: Although Hitachi has been assembling semiconductor
memories and microprocessors in the Las Colinas area of Irving, Texas
since 1978, it was not until 1989 that they expanded operations to
include their first wafer fabrication capability outside of Japan. The
new facility can now provide submicron products fully manufactured in
the United States, for use in data communication equipment, office
automation equipment, industrial equipment and home appliances.
The Hitachi commitment to quality is recognized worldwide.
1. The use of plastic sleeve on the wet end of the pump allows the
mechanical seal to totally isolate the fluid to plastic materials.
2. "O" ring seals between the plastic sleeve and impeller, and between
the impeller and the lock nut, assure no metal in contact with solution.
3. The front bearing can be pulled back on sliding bars for easy
maintenance and flexibility to accommodate virtually any sealing
4. Heavy duty, sealed, self-aligning ball bearings widely spaced on shaft,
offer maximum stability and long life. The sliding bar in combination
with these bearings reduces stresses from thermal expansion and
provides first critical speed of over 20,000 rpm with virtually zero shaft
5.The relatively short, large diameter stainless steel shaft of stepless
design eliminates stress concentrations and possible failure.
6. Cam lock bearings are utilized to allow easy adjustment of the
7. Effective "O" ring sealing prevents leaks and blow-outs.
8. Choice of the threaded ends or welded flanges.
9. Key driven molded impeller with investment casting insert to insure
positive drive, provide additional rigidity to impeller at higher
temperatures and heads, as well as to prevent damage from reverse
10. Open pedestal design avoids corrosion damage from drippage.
11. Heavy wall, homogeneous injection molded casing.
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In the 1950, Vanton developed a revolutionary all-plastic pump for use in conjunction with the first heart-lung device. The design limited fluid contact to only two non-metallic parts: a plastic body block and a flexible liner. This was the birth of our Flex-I-Liner rotary pump. Its self-priming sealless design made it an industry standard for the handling of corrosive, abrasive and viscous fluids as well as those that must be transferred without contaminating the product. Vanton now offers the most comprehensive line of thermoplastic pumps in the industry.
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(+44) 01260 277040
Vanton Pumps (Europe) Ltd.
Unit 4, Royle Park
Congleton CW12 1JJ