Edited by Alan L. Hitchcox

Hydraulic Plow Balance System provides multiple benefits not only for plowing snow, but for any equipment where advantages can be gained by controlling ground pressure of an implement.

Those of us who live in northern climates don’t need to be reminded that we could see our first substantial snowfall within the next few weeks. But even if you live far enough south to escape an annual deluge of the white stuff, the same innovative technology applied to snow removal might be applicable to equipment in your neck of the woods.

Wojanis Supply Co. Inc., Coraopolis, Pa., developed the Plow Balance System (PBS) as a hydraulic solution to provide multiple benefits to public and private organizations responsible for snow removal. In a conventional snow plow, the plow blade rests on the ground, and the forward motion of the vehicle pushes anything in its path off to the side. Snow plows typically weigh 2500 to 4000 lb, so allowing the entire weight to contact the ground subjects the bottom edge of the plow blade to rapid wear, damage from objects protruding from the road surface, and generates high friction, which wastes fuel.

Innovative hydraulic solution
The PBS circumvents these liabilities by using hydraulics to cause the vehicle to bear most of the plow’s weight, instead of allowing the full weight of the plow to scrape against the ground. This is done by applying hydraulic pressure to the lift (usually the cap) end of the cylinder so that the blade exerts much less ground pressure when in the lowered position. Furthermore, the PBS does not alter conventional operation of the plow.

The Plow Balance System consists primarily of a hydraulic integrated circuit contained within a manifold. It comes with instructions and components needed to retrofit a conventional plow into one that exerts only 500 to 1000 lb of ground pressure. As a result, blade life can be increased as much as ten times. It also helps prevent damage to road surfaces, increases fuel economy, and reduces noise.

The PBS comes in a variety of configurations to match the particular controls of the snow plow’s hydraulics. For example, one version is designed for hydraulic systems powered by a gear pump, whereas two others are designed for use with axial-piston pumps to take advantage of energyefficient pressure compensation and load sensing controls.

Quick and easy retrofitting
Installing the Plow Balance System is relatively simple. After the manifold and control module provided have been mounted, hydraulic lines that had been routed fluid to and from the plow’s elevation valve in the original system are simply rerouted to two ports on the PBS. Hydraulic lines to the cylinder are then connected to two outlet ports of the PBS, and any load-sensing lines are rerouted in similar fashion.

Once electrical lines for controls and valve solenoids have been connected, the plow’s ground pressure can be set. This is done by letting the plow rest on a vehicle scale. Then, with the PBS energized, a pressurecontrol valve is adjusted until the plow blade exerts the desired force onto the scale.

Any time the operator wants to apply the full weight of the blade to the ground — for scraping off especially stubborn ice, for example — he or she simply flips a switch to deactivate the PBS. In this mode, hydraulic fluid passes through the manifold unrestricted, so the plow’s hydraulic system operates as it did originally.

More than just snow
But what about other applications? Doug Goldstrohm, sales and business administrator at Wojanis, says the Plow Balance System has already been applied to the brush elevation circuits of underbelly sweepers of at least two manufacturers. Here, the PBS system controls ground pressure of the brushes, which makes sweeping more effective and extends the life of brushes.

Goldstrohm says Wojanis is also working with a manufacturer of road resurfacing equipment to control the ground pressure of blades that remove pulverized asphalt after it has been ground off a road surface.

This information was provided by Doug Goldstrohm, of Wojanis Supply Co. Inc. For information, contact him at DougG@wojanis.com, call (724) 695-1414, or visit www.wojanis.com.