TL-107

 

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

corrosive service.

The front bearing can be pulled back on

sliding bars for easy maintenance and

flexibility to accommodate virtually any

sealing arrangement.

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

Hitachi

INDUSTRY:

ENTITY:

SOLUTION(S) PUMPED:

PUMP TYPE(S):

Electronics

Hitachi

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

requirements.

 

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

construction.

 

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

keep up.

 

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

disappeared.

 

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.

DESIGN FEATURES

 

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

arrangement.

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

deflection.

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

impeller.

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

rotation.

10. Open pedestal design avoids corrosion damage from drippage.

11. Heavy wall, homogeneous injection molded casing.

 

>

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Copyright 2016 - Vanton Pumps (Europe) Ltd - All rights reserved

About Us

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.

 

 

Stay in touch

mail@vantonpump.com

(+44) 01260 277040

Vanton Pumps (Europe) Ltd.

Unit 4, Royle Park

Royle Street

Congleton CW12 1JJ

UNITED KINGDOM

www.vantonpump.com