O-Pro® Seal Technology



Packing was designed to leak

But it doesn't have to be that way

With Viking Pump's patented O-Pro® Sealing Technology, you keep your product where it belongs

  • Inside the pump
  • Off your floors


We listened to our customers and engineered a seal that reduces loss of product due to leakage.

What can we help you with?

Before and After O Pro
Replace Packing or Mechanical Seals with O-Pro®

Each O-Pro® Seal design option replaces packing or a mechanical seal by occupying the internal bracket cavity with a machined seal gland. Utilizing O-rings to seal externally on the bracket and internally on the shaft, a combination of O-rings and lubricating grease provide a robust seal. This prevents process fluids from leaking out of the pump. 

O-Pro® Barrier Seal

The O-Pro® Barrier seal also replaces the bracket bushing - which allows the entire bracket to be sealed off from process liquid.

o pro barrier seal spinny gif

O-Pro® Cartridge Seal

The O-Pro® Cartridge seal allows for an easy retrofit while addressing any need for stainless steel seal construction.

cartridge seal o pro spinny gif

O-Pro® Guard Seal

The stainless steel construction utilizes a sleeve that is secured to the shaft to address any shaft wear concerns to ensure superior performance.

guard seal o pro spinny gif

Speak to an Expert



With over 110 years of experience providing positive displacement pumping solutions, Viking Pump has a rich, lengthy history of providing engineered solutions for tough applications. We have dedicated sales and field support specialists who are supported by a team of customer service representatives and engineers. Our knowledgeable team of application engineers available to help with product selection and technical support. USA based company with vertically integrated manufacturing facility. 



Our state-of-the-art testing equipment is used to confirm performance prior to shipments. Our world-class lab gives Viking Pump the ability to test our pump designs across a range of relevant variables. 

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Chocolate Plant Elimates Leakage with O-Pro® Barrier

A major producer of chocolate confections in the eastern United States had been operating many Viking pumps on a variety of confectionary liquids for decades.

Many of these gear pumps have shaft packing, an extremely reliable means of preventing leaks, but which require some…

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Distributor Spotlight | Kerr Pump & Supply

Kerr Pump & Supply, a notable first distributor of Viking pumps, has an illustrious 100+ years business history in the Detroit area. The company began manufacturing electric and steam driven centrifugal pumps under the name of Kerr Machinery & Supply, founded in 1905 by Alexander M. Kerr, along with his two sons, David and Robert, and…

glue on a board


Adhesives are a group of substances, such as cement, glue, mucilage, and paste that are capable of holding materials together by surface attachment. Adhesives are made from many different basic materials, among them dextrin, latex, silicones, liquid rubber, resin, sodium silicate, and starch. 

laying asphalt

Asphalt Cement

Clean asphalt contains no fillers and is an oil based liquid. It is primarily used in paving roads, waterproofing liquids, and paints. Typically they are handled at elevated temperatures to reduce the viscosity of the asphalt. The pump needs a source of heat like jacketing or electric heat to prevent the product from solidifying in the pump.

laying asphalt

Asphalt Emulsions

Emulsions are asphalt suspended in a mixture with water or other liquids. This is done to ease the application of the asphalt. Uses would be crack filling, coating roadways, or waterproofing. These emulsions are shear sensitive and must be handled with care.

Trucks with logs on their way to a pulp mill

Black Liquor Soap

A natural intermediate byproduct of kraft pulping, black liquor soap is the rosin and fatty acid content that floats to the top as black liquor is left to settle. It is skimmed off and can be used as a raw material for tall oil production. Black liquor soap can be somewhat abrasive and range in viscosity from 22 to 5500 cP, depending on the temperature it is handled at.

Person caulking an object


Caulks can be silicone, acrylic, or latex based adhesives and sealants used in industrial and home construction. Typically high viscosity & shear sensitive.

Chocolate bars


Cacao beans are roasted, ground up, and mixed with oils to get a semi-liquid which is the beginning point in the making of chocolate. Early stage chocolate is known as bitter chocolate. Add sugar and it is known as sweet chocolate. Add milk for milk chocolate. If the chocolate has been thinned down it is chocolate liquor. It can be diluted with fats like palm nut or coconut oils.

Jar of cosmetic cream

Creams (Medicinal, Cosmetic)

Creams are typically for personal use by consumers for cosmetic and surface medical treatments. Physical properties and chemistry can vary greatly depending on the cream base and added substituents. Some creams will be petroleum based like Petroleum Grease, while others may be emulsions suspended in water. They typically are shear-thinning mixtures.

detergent pod being placed into dish washer

Detergent Slurry

Detergent Slurry is a blend of liquid surfactant with powdered and granulated materials, such as builders and additives, that help to improve surfactant and cleaning performance.

shingles on roof

Filled Asphalt

Filled asphalts contain particulate used in the liquids’ end applications. Examples of this would be roofing materials and hot mix plants. Typically they are handled at elevated temperatures to reduce the viscosity of the asphalt mixture. The pump needs a source of heat like jacketing or electric heat to prevent the product from solidifying in the pump.

Injecting grease


Commonly referred to as lubricating, automotive, or bearing grease. Generally mixtures of a mineral oil with one or more metallic soaps; the most common are those of sodium, calcium, barium, aluminum, lead, lithium, potassium and zinc. The texture of grease may be smooth, buttery, ropy, fibrous, spongy or rubbery and have a variety of viscosities.

High fructose corn syrup in bottles on conveyer belt

High Fructose Corn Syrup (HFCS)

High Fructose Corn Syrup (HFCS) is usually followed by the percentage of fructose in the liquid, ranging from 42 to 55%. It is most commonly used in soft drinks, jams, and jellies as a sweetener. Temperature regulation is relevant because discoloration of the liquid could occur at elevated temperatures.

Glue gun ejecting hot melt

Hot Melt

Hot Melt adhesives are thermoplastic polymers that soften (become less viscous) when heated. Applied by a local system that melts the adhesive and adjusts pump speed to match the speed of the converting machine.

Candles drip drying


Waxes can be natural secretions of plants or animals, such as beeswax, or by-products of petroleum refining. Wax is commonly used in the paper and boxboard industries to make products such as cartons and paper packaging moisture resistant. Wax can also help prevent food products from sticking to paper packaging.

ink roller


Inks for flexible packaging are shear sensitive liquids that can have a variety of solvents, waxes, surfactants, and semi-solid resin particles, and pigment load concentrations that bring with them abrasive wear and chemical compatibility concerns.

Isocyanate in a lab


Also known as TDI, MDI, or diisocyanate. Isocyanate is used as a hardening or curing agent in polyurethane foams, industrial coatings, elastomers, inks, and resins. It is extremely sensitive to moisture in the air and hydrocarbons making air-tight seal options extremely critical.

Latex gloves on a conveyer


Latex is the generic term for emulsions of polymer in water that is stable. These emulsions can be natural or be synthetically made. This liquid is typically very shear sensitive and requires care when pumping.

Tech working on lecithin in lab


Lecithin is a mixture of triglycerides, fatty acids, and carbohydrates that typically ranges in viscosity up to 5000 SSU, but may be more viscous depending on make-up and temperature. It is typically derived from soybean oil but may also be obtained from egg yolks, corn, or other vegetable seeds.

Pigs in a pen

Liquid Fats

Recycled animal fats and vegetable oils are used in the production of animal feeds for many reasons including the acceleration of growth rates, improved taste, providing essential fatty acids and to act as a binder for producing feed pellets. Typical products include oils derived from corn, soybeans, peanuts as well as animal fats.

Hand lotion


Lotions are typically for personal use by consumers for cosmetic purposes. Most lotions are used for softening or moisturizing skin. Some lotions are used to deliver medicine to unbroken skin as well. Typically these are emulsions with oil suspended in water and shear-thinning.

Oil being poured into vehicle

Lube Oil Blending

Local blending plants take bulk petroleum or synthetic base oils and mix them together with additives to create unique oil blends for specific applications and customers.

mill oil plant

Mill Oil

Is a lubricating oil used in the processing of steel. Various formulations are utilized depending on the process such as hot rolling, cold rolling and tubular rolling of steel.

Cows in a dairy


Molasses is defined as the syrupy mother liquor left after sucrose has been removed from the cane juice by concentration. If only one crop of crystals had been removed, it is called First Molasses. If the second crop has been removed, the product is termed Second Molasses, and so on. When no more cane sugar can be extracted it is called Final Molasses or Black Strap Molasses.

Peanut Butter

Peanut Butter

Peanut butter is made from mixing ground up peanuts with various additives and fillers. From the mixer, peanut butter is pumped through a deaerator and/or heat exchanger to remove entrained air and drop the temperature prior to being pumped to the jar filling machines. 

insulation foam blocks


Polyurethane foam is produced when a polyether is treated with a isocyanate in the presence of water and a catalyst, as well as fillers, dispersing and emulsifying agents, etc. The water reacts with the isocyanate group to cause cross linking and curing, and also produces carbon dioxide which causes foaming. May also be known as Isocyanate liquid.

white glue in glue bottle

Polyvinyl Acetate (PVAC)

Poly Vinyl Acetate, or PVAC, is a colorless, odorless, tasteless, non-toxic, transparent, thermoplastic solid. It is used in latex water paints, in hot melt and other types of adhesives, for coating and finishing fabrics, as a component of lacquers, inks and in caulking compounds and chewing gum. PVAC is insoluble in water, oils and fats, but soluble in alcohols, esters, benzene and ketones.

Cleaning chemical being sprayed onto table

Quaternary Ammonium Compounds

Quaternary ammonium compounds, also known as quats, are used as disinfectants in restaurants, hospitals and homes. They are also used as surfactants, fabric softeners, and antistatic agents in products like shampoo.

Asphalt being reclaimed

Reclaimed Asphalt

Reclaimed Asphalt is typically a dirty or filled asphalt containing a bitumen blend with solids that could be limestone or rubber based. These solids result in very high viscosities and abrasive nature, resulting in the need for extra clearances, low run speeds, and the inclusion of hardened parts.

Resin being applied to floor


Resins are high viscosity liquids with potentially shear sensitive (thinning) components, and made up of solvents, waxes, surfactants, and semi-solid resin particles all with various chemical compatibility concerns. These resins can be used in polyurethanes, epoxies and other adhesives. In some cases, resins contain pigments that bring with them abrasive wear concerns.

Tires made from rubber cement

Rubber Cement

Rubber cement, also referred to as contact cement covers a wide range of materials; some may be emulsions sensitive to shearing; others may be flammable because of the solvent carrier; others may be water solutions, which are used in a variety of adhesive-type applications. Due to the variance in material and solvent used, the viscosity varies greatly.

Stack of corrugated cardboard boxes

Starch Adhesive

Starch based adhesives are used in the paper and corrugating industries. The raw starch is derived from a variety of plants such as corn, wheat, and potatoes. They tend to be shear sensitive (thickening) and are mixed in equipment commonly referred to as a starch kitchen.

Tall Oil soap factory

Tall Oil Soap

A natural intermediate byproduct of kraft pulping, tall oil soap is the rosin and fatty acid content of black liquor that is skimmed off and used as a raw material for tall oil production. Tall oil soap can be somewhat abrasive and range in viscosity from 22 to 5500 cP, depending on the temperature it is handled at.