Technical Resource
Gear Pump for Paint Transfer
Plant transfer of latex, enamel, polyurethane, industrial coatings, and inks. Tank to tank, tote or drum into process, load-out to trucks and drums.
This page is for plant transfer of latex, enamel, polyurethane, industrial coatings, and inks. Tank to tank, tote or drum into process, load-out to trucks and drums. NAPCO builds the 2-inch and 3-inch rotary gear pumps for that job. See general industrial for the rest of the fluid list.
NAPCO does not make paint.
What the plant is actually pumping
Resin and solvent come off the truck into mixers. Mill-base moves to let-down. Finished coating goes to stocking tanks, then to drums, totes, or a transport.
Blackmer publishes that same list for gear pumps on a coatings line: resin and solvent unloading, mixer feed, additives, grind and dispersion, lengthening tanks, stocking, small tanks, drums, transports. Spray and application sit after that. This page stops at transfer.
Lower volume is the same job. A tote dump into a 200-gallon tank is still transfer.
Why a rotary gear pump
Gears mesh and carry a fixed volume each turn. Shaft speed sets flow. System backpressure sets the load, up to the pump rating.
Latex is a polymer-in-water emulsion used in paints and coatings. Viking calls it shear-sensitive and prefers a positive-displacement gear or lobe pump run slowly, because flow still tracks RPM when the batch thickens. Their latex viscosity band is 2,000 to 20,000 cP, depending on solids and temperature, specific gravity about 1.0 to 1.2. That band is latex binder, not a finished architectural paint number. Read the TDS for enamel, polyurethane, or mill-base.
NAPCO pumps prime themselves. Reverse the motor and the same line unloads.
Centrifugal flow drops as viscosity rises. Details: rotary gear pump vs centrifugal pump. Sizing: how to size a rotary gear pump.
Wilden lists AODD pumps on the same plants for resin, solvent, filtration, and loading, and sells them as portable, run-dry, and seal-less. A rotary gear pump is what you bolt down for continuous tank-farm and mixer-feed transfer.
Housing and gears
Pick the metal for the water and the solvent. Pick the gear elastomer for the solvent.
Ductile iron or stainless
Ductile iron (C models) is the housing when the coating does not attack iron. Most solvent-borne transfer lands here.
Stainless (S models) is the housing when water, pH, or the solvent package attacks iron. Viking says stainless may be needed on some water-based and latex varieties. If you do not have pH or a full SDS, spec stainless. Comparison: stainless steel vs ductile iron pumps.
Nitrile or Viton gears
Nitrile gears are standard, rated to 240°F. They hold up on waterborne latex and on many petroleum carriers. Benzene, toluene, and xylene swell them.
Viton gears are the option for those aromatics and for sustained service above 240°F. Viton seals are already on every NAPCO pump. The gear is the part you change with the solvent.
MEK, acetone, and a lot of lacquer thinners attack nitrile and Viton. Send those formulas in before you order gears.
Viscosity and pigments
Viking’s 2,000 to 20,000 cP is latex emulsion. Enamel, polyurethane, and mill-base need their own TDS numbers.
TiO2, iron oxide, and carbon black wear metal internals. Viking calls that out on paint transfer. NAPCO uses elastomer gears. Run them slow. Strain tramp solids.
Performance tables on the product pages are water at rated speed. Thicker coatings often need a lower RPM. Size from measured viscosity at pumping temperature, plus flow and pressure.
Which model
PA300C
The PA300C is the 3-inch ductile iron pump. 158 GPM at 280 RPM and 10 PSI. 140 GPM at 100 PSI. 13.4 bhp at 100 PSI. Max 100 PSI, max 280 RPM, 173 lbs.
Plant pump-over, tanker load and unload, high-volume coating transfer.
PA200C
The PA200C is the 2-inch ductile iron pump. 69 GPM at 190 RPM and 10 PSI. 60 GPM at 100 PSI. 5.7 bhp at 100 PSI. Max 100 PSI, max 190 RPM, 114 lbs.
Tote and drum work, smaller batch lines.
Stainless
PA300S or PA200S when iron is the wrong metal. Same flow, pressure, weight, and port as the C model of that size. Nitrile gears unless the solvent is aromatic, then Viton.
Both sizes prime themselves and run either direction.
Rebuild
A factory kit is gears, seals, bearings, and gaskets. 2 to 5 hours on the 3-inch (PK300C). 2 to 4 hours on the 2-inch (PK200C). Hand tools. The product pages put kit cost at 30 to 50 percent of a new pump.
Jobs this pump should not take
Spray-booth circulation, airless spray feed, and paint-kitchen metering are different machines. Codinter describes kitchen circulation as a loop to the gun at 80 to 125 PSI at the drop. NAPCO’s tested ceiling is 100 PSI, and the duty here is tank-to-tank, not a gun loop.
AODD stays the portable, filtration, and run-dry option (Wilden).
If the gears swell or the housing rusts, change the elastomer or the metal. The pump type can stay if the job is still surface transfer.
FAQ
What is a gear pump for paint transfer?
A rotary gear pump used to move coating between tanks, totes, drums, and loading points. NAPCO's PA300 and PA200 series are built for that plant duty.
Iron or stainless? Nitrile or Viton?
Iron when the coating does not attack iron. Stainless when water, pH, or solvent makes iron a risk, including some latex. Nitrile gears on waterborne and petroleum carriers, to 240°F. Viton on toluene, xylene, benzene, or hotter service. Ketones fail both.
Can it pump latex?
Yes, on surface transfer. Viking treats latex as shear-sensitive and runs gear pumps slowly. Nitrile gears. Keep RPM down. Spec stainless if pH or water content is unknown.
PA300C or PA200C?
PA300C up to 158 GPM. PA200C up to 69 GPM. Both 100 PSI. S models if iron is wrong.
Will a centrifugal hold flow?
Usually not, once the coating is thick. A gear pump moves a set volume each turn.
Specifying a paint transfer pump
Send fluid type, viscosity at pumping temperature, flow, pressure, temperature, and aromatic or ketone content if you have it. We will confirm housing, gears, and size.