Shown is the close-coupled pump used at
Sierra Lumber Co. The Flex-i-liner®
progressive cavity operation requires no
packing or gaskets.
Pump Moves Glue Easily
Pulp and Paper
Sierra Lumber Company
Polyvinyl acetate glue
FLEX-I-LINER Sealless Self-Priming Peristaltic Pumps
Reprinted from PLANT SERVICES
Paul Wnuk, General Manager
Jim O'Bannon, Finger Jointer Supervisor, Sierra Lumber Co., Stockton, CA
Morgan C. Larkin, Editor-West
Sierra Lumber Company in Stockton, CA, manufactures components for
wood doors for home building. The door framing is assembled using
glued, interlocking finger joints, which are accurately cut and fit.
A chronic problem at the jointer machine had been the pumping of a
viscous, catalyzed, polyvinyl acetate glue to the point of application.
Plugging and expensive parts replacements caused frequent difficulties.
Personnel at Sierra felt that a pump more compatible with their
procedure and materials would alleviate the problems.
The parameters for the glue pump included continuous delivery of up to
4 gpm against a 10 psig head. Flow characteristics would be governed
by the 150-cp viscosity of the glue. Although the catalyst was already in
the glue, curing was slow enough so that set-up was minimized in
transport and was timed to be effective on the wood when joined.
Research revealed a rotary, squeegee-type cavity pump in which the
fluid is isolated from moving parts.
With this background, research revealed a rotary, squeegee-type cavity
pump in which the fluid is isolated from any moving mechanical parts.
The pump dimensions are about 15 inches long, 7 inches wide and 8
inches high, allowing a compact installation. Hose connections are 1
In operation, a close-coupled ¼-hp, 1750-rpm motor turns a cylindrical
rotor on an off-center shaft, thereby providing a cam-like action. The
rotor oscillates inside a flexible, neoprene liner, deforming this to create
a non-backflow seal and cavity within a circular opening in a heavy-duty
Teflon® pump block. The sealing zone of the liner, moved by the
off-set rotor, induces inlet flow through the intake and simultaneously
forces the glue through the outlet. The inlet and outlet cavities between
liner and block are separated from one another by a raised segment of
the liner, which extends into the block.
Glue delivery thus is carried out with many of the advantages of positive
displacement. The pump is self-priming, withstands dry-running
without damage and is immune to air bubbles or vapor lock. Agitation
of the fluid is minimized.
The components of the pump are comprised of a cast iron motor
bearing plate through which the shaft connects with the phenolic resin
rotor. Bearings are permanently lubricated and there is no need for a
stuffing box. Not only are mechanical parts isolated from the glue, but
conversely, there is no danger of contamination of the fluid by any
The liner is cylindrical and has a thick wall. The deformation and
pumping movement is well within the flexing limits of neoprene.
Change of liner for preventive maintenance is required about once a
year. The pump is assembled between a cast-iron front plate bolted to
the motor plate by four lag bolts. Flanges on the flexible liner are
received in machined grooves in the plates to assure total closure
without seals. Disassembly and reassembly of the pump require about
The only sliding contact is between the rotor and the inside surface of
the liner. This friction is alleviated by the addition of seven drops per
week of a silicone lubricant applied through a head-mounted oil cup.
When idle, the pump is its own check valve and the liner-block contact
prevents back flow.
One pump has been in service for 1-½ years and a second was put into
operation about 6 months ago.
There has been no interruption of the jointer due to failure of glue supply
since the pumps were installed. Sierra Lumber engineers feel that the
sealless, squeegee pumps have solved their problem.
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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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Vanton Pumps (Europe) Ltd.
Unit 4, Royle Park
Congleton CW12 1JJ