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Teflon® body and Hypalon® rotary

diaphragm enable pump to handle both

sulfuric and caustic solutions in

recirculating scubber service.

FLEX-I-LINER® rotary diaphragm pump

Flexible Liner Pump Cuts

Scrubber Maintenance






Gaylord Foundry Equipment

Sulfuric acid, Caustic solutions

FLEX-I-LINER Sealless Self-Priming Peristaltic Pumps

Nonmetallic wetted parts handle 98% sulfuric acid,

50% caustic, and up to ½" solids with ease




Packed tower recirculating scrubbers made by Gaylord Foundry

Equipment use 98% sulfuric acid and 50% caustic solutions as

neutralizing agents in cold box processes to capture amine gases and

sulfur dioxide. All components of the scrubber systems must be

compatible with these harsh chemicals.


The recirculating pump service required accurate, repeatable and

reliable metering, self-priming and the capability of handling solids up

to ½" in diameter without damage.


For the original design, a bellows-type pump was used. Monitoring of

the scrubber systems throughout North America revealed excessive

pump maintenance and costly downtime because of delays in

replacement parts deliveries.


The company sought a better pump for the service, and found it in a

flexible-liner, nonmetallic unit with only two parts in contact with the

neutralizing solution.


Driven by a ¼-hp electric motor, the rotary diaphragm pump uses a

Teflon® pump casing and a Hypalon® flexible liner. The compact and

rugged pump uses a progressive, compressive force imposed by an

eccentric lobe rotating against an elastomeric diaphragm to propel

fluids trapped between the outer surface of the diaphragm and the inner

surface of the plastic pump casing.


Leak- and maintenance-prone components such as stuffing boxes,

glands, shaft seals, gaskets and check valves are not required in the

flexible liner pump. It is sealless, self-priming and capable of running

dry without damage to the pump or the motor. The only wearing part is

the flexible liner, which can be replaced in minutes at low cost. The

vice president of the company manufacturing the scrubber systems

reports that the flexible liner pumps have improved accuracy and

dependability and practically eliminated downtime and maintenance.

They are now standard on all new systems. Older systems are being

retrofitted in the field whenever pump problems are reported.



Acids, Caustics, Salts, Abrasive Slurries, Solvents,

Chlorides, Viscous Fluids


Vanton self-priming FLEX-I-LINER pumps are precision engineered with

relatively few parts to provide efficient handling of corrosives, volatile

fluids, abrasives and other products safely and dependably. Capacities

to 40 gpm; discharge pressure as high as 45 psig; temperatures to

250°F. Suitable for vacuum service and for gases, liquids and viscous

fluids up to 6,000 SSU. The Vanton FLEX-I-LINER can operate in either

direction with equal effectiveness. It is recommended for slurries with

as much as 20% soft solids and for gas service handling a maximum of

1 cfm, as well as the handling of clear, volatile fluids.




No Stuffing Boxes, Glands, Shaft Seals or Gaskets


The design of the Vanton Pump has eliminated the need for stuffing

boxes, packing glands or mechanical shaft seals, completely removing

the possibility of hazardous and wasteful external leakage. This design

also avoids oil or grease contamination of pumped fluids. Stuffing

boxes, shaft seals and gaskets are not necessary since the flanges on

the flexible liner straddle the body block and are pressed to its sides by

concentric machined grooves in the bearing sleeve and cover plate.

This confines the fluid to a channel formed by the outer surface of the

flexible liner and the inner surface of the body block while all

mechanical action and moving parts are on the inside of the flexible



No Check Valves


Internal valves are not necessary. The absence of valves adds to the

simplicity of construction and eliminates maintenance due to valve

stickiness and wear. Sensitive fluids which might otherwise be

damaged by opening and closing of check valves are readily handled by

the FLEX-I-LINER pump.


Self-Priming/Wet or Dry Operation


Vanton Flex-i-liner pumps will prime in any operating position without

priming devices. Air bubbles will not cause locking or seizing of the

pump nor impair efficiency... and running dry for extended periods is

not detrimental.




At selected RPM, depending on the fluid, the gentle pumping action

prevents churning or foaming. This prevents excessive settling out of

suspensions and avoids breakdown of various latex emulsions and

other similar sensitive liquids.


External Bearings


Both shaft bearings are housed in a cast iron pedestal, which is external

to the fluid cavity itself. The rotor bearing is completely protected

within the phenolic rotor and sealed off with a plug on one side and a

spring-loaded phenolic bearing guard on the other, which rides on the

lapped surface of the bearing sleeve. Bearings are sealed-in,

permanently lubricated ball bearings and operate in a clean, isolated

non-corrosive atmosphere.


Low Maintenance


FLEX-I-LINER pumps, by eliminating stuffing boxes, shaft seals, gaskets

and check valves remove the major causes of pump maintenance. The

only wearing part is the low cost flexible liner, which can be replaced



Easy Servicing


There is no need to remove the pump to a workbench for expensive or

intricate servicing... or to remove it from the base plate, which could

affect the precise alignment of shaft to motor. With the external bearing

design, only the inexpensive flexible liner may require replacement after

long periods of service. This can be accomplished in a matter of

minutes, even by an inexperienced operator, and with no special tools.




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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


(+44) 01260 277040

Vanton Pumps (Europe) Ltd.

Unit 4, Royle Park

Royle Street

Congleton CW12 1JJ