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TL-124

 

Original Vanton polypropylene duplex pump

with Hypalon flexible liner. This pump

has been under test for 1-½ years,

handling a variety of corrosive fluids.

These 35 Flex-i-Liner® Duplex Teflon

Pumps with Viton flexible liners are

scheduled to replace the troublesome

diaphragm pumps at Boeing's Wichita,

Kansas facility. They will be handling

a variety of acids, caustics and

solvents.

Maintenance at
the Boeing Company

INDUSTRY:

ENTITY:

SOLUTION(S) PUMPED:

PUMP TYPE(S):

Metal Finishing

Boeing Company

Acid salts, Caustic solutions, Chromic acid, Hydrochloric

FLEX-I-LINER Sealless Self-Priming Peristaltic Pumps

 

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Reprinted from PLANT SERVICES

By Charles M. Boyles, C.P.E., Editor-in-Chief

 

Upgraded system for handling corrosives improves

safety and reduces waste

 

The building has the latest in environmental controls, which provide a

safer workplace for employees while increasing productivity and

protecting the environment.

 

One of the reasons the Boeing Company has become the largest

aerospace firm in the United States is its published commitment to cut

waste and boost productivity with less time at the lowest possible cost.

Coupled with this high quality and low cost drive is Boeing's emphasis

on changing manufacturing processes to improve worker safety and

reduce the environmental impact of its operations.

 

When the huge — more than a million square feet — manufacturing

process facility in Wichita, Kansas was completed in September 1991, it

was hailed as one of the largest and most technologically advanced

facilities of its kind in the world.

 

It is truly a state-of-the-art metal finishing and painting facility. There,

critical parts for every Boeing commercial jet liner undergo a variety of

corrosion-inhibiting processes to extend service life.

 

According to Boeing's Health and Safety Administrator, Chris Frederick,

construction of the manufacturing process facility allowed Boeing to

consolidate many of these chemical processes in a single building. The

building has the latest in environmental controls, which provide a safer

workplace for employees while increasing productivity and protecting

the environment. Specific emphasis was placed on incorporating an

automated chemical addition system in the facility design. The system

reduces direct operator exposure during tank filling and periodic

chemical additions. Also, it has a sophisticated chemical milling

recovery system.

 

The recovery system regenerates sodium hydroxide used for chemical

milling and removes the dissolved aluminum from the process. These

products are recovered and recycled as part of Boeing's environmental

program. Boeing is determined to comply with and exceed EPA

regulations. Existing chemical addition practices associated with

charging and maintaining pH control in metal finishing tanks were

considered impractical for this modern facility.

 

A better way

 

In the past, many of the chemicals used were received in powdered

form and were handled by production process mechanical cranes. This

approach was relatively slow. The powdered chemicals did not

dissolve readily in the finishing tanks. Also, the employees were subject

to possible chemical exposure during the transfer of powders that had

hardened in drums.

 

Boeing conducted a thorough examination of the equipment design and

the potential hazards for employees. From this study, Boeing decided

to standardize on the use of liquid formulated metal finishing chemicals

instead of powdered.

 

The new liquid chemical addition system uses bulk loads of the

chemicals for initial tank charging. The new system has dedicated

pipelines to transfer the chemicals to specific tanks safely. This system

completely eliminated any manual contact with the chemicals.

For the daily or "on demand" chemical additions, Boeing engineers

specified 350-gallon portable tanks with flow-controlled chemical

metering pumps. Thirty-six chemical metering stations were

established to transfer chemicals safely from the portable tanks to the

appropriate metal finishing tank.

 

The corrosive, hazardous and toxic chemicals — nitric, sulfuric,

phosphoric, hydrochloric, hydrofluoric, chromic acids, acid salts,

caustic solutions and solvents — required the closed piping systems for

safe handling.

 

The variety of chemicals Boeing handled dictated the use of non-metallic

pumps. Non-metallic pumps ensure resistance to corrosion and avoid

the potential for metallic contamination in process solutions.

 

Boeing engineers also wanted to test several different types of positive

displacement chemical metering pumps for comparative evaluation.

Initial studies resulted in the decision to install electric and air operated

diaphragm type pumps.

 

Although the new liquid handling system was a decided improvement

over the powder drums, there were problems with the diaphragm

pumps. They were relatively noisy and required pulsation dampers to

ensure even flow of chemical additions. This resulted in costly

maintenance procedures.

 

In keeping with Boeing's ongoing quality improvement program, the

maintenance department decided to test a non-metallic peristaltic

metering pump that was in use for handling a wide range of corrosive

chemicals.

 

The pump had to meet some basic requirements. It had to be sealless

and self-priming. Fluid contact components had to be non-metallic.

Also, the pump had to preclude the danger of external leakage or

fugitive emissions — in keeping with Boeing's environmental

commitment.

 

Boeing engineers selected a pump with a polypropylene casing — body

block — and a flexible liner made of Hypalon™ — a chloro-sulphonated

polyethylene elastomer. They also specified that the pump be supplied

with a variable speed motor and speed controller for controlled

metering.

 

According to Boeing's Maintenance Supervisor, Bert Montgomery, and

Maintenance Project Engineer, Lawrence Hole, the test pump has been

in service for 1-½ years without any problems.

 

Results

 

As a result of the successful test, the project engineers wrote a detailed

specification for a similar unit with duplex pumps. The pumps are

constructed of a single group of non-metallic materials that are inert to

the corrosive chemicals and solvents handled by the portable tanks.

Boeing engineers decided on this combination of pump materials:

pump casing — reinforced Teflon™, flexible liner — Viton™, expansion

rings — Delrin™, and unpigmented polypropylene piping. This design

offers complete interchangeability of pumps and spare parts. This

translates into low maintenance inventory. In keeping with Boeing

engineers' thoroughness, they also specified an organic stabilized

grease for lubrication.

 

Boeing's manufacturing process facility is now replacing its diaphragm

chemical metering pumps with self-contained metering pumps at 35

chemical metering stations. Also, Boeing is experimenting with a

pumping system for its soluble machine coolant recycling center.

 

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.

 

 

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mail@vantonpump.com

(+44) 01260 277040

Vanton Pumps (Europe) Ltd.

Unit 4, Royle Park

Royle Street

Congleton CW12 1JJ

UNITED KINGDOM

www.vantonpump.com