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
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
Reprinted from CHEMICAL PROCESSING
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
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
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.
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
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
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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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