Air-Powered Dock Levelers and Trailer Restraints Improve Safety and Productivity at Loading Dock

Today's loading dock is an increasingly busy place, requiring innovative equipment to keep pace with the latest trends in materials handling. In addition, manufacturing, warehouse and distribution center managers face difficult choices when selecting dock equipment. They have to consider productivity, ergonomic, safety, and environmental issues to keep pace with their unique demands and to ensure the highest return on their investment.

With 62% of all new trailers on the road today equipped with air-ride suspensions, dock leveler stump out has become an ever-increasing issue on the dock. During loading operations, air-ride suspension trailers can lower 3 to 8 inches. Stump out occurs when the dock leveler ramp stops near dock level, but the lip continues to lower with the trailer, interfering with the proper operation of the dock leveler. The steep lip angle creates a potentially unsafe condition, resulting in lost productivity and money-draining damage to fork trucks, dock levelers and product.

Previously, expensive hydraulic dock levelers provided the only solution to stump out. Kelley's airForce Technology delivers all the air-powered advantages introduced in 1995 with the original Kelley FX -- durable, simple, clean-running operation, with lubrication- and adjustment-free activation and minimal moving parts while also eliminating stump-out with special airDefense sensor rollers that travel along a reinforced cam, providing fluid free-float motion and purging stump-out. Kelley's airDefense also provides a measure of free-fall protection in the event of premature trailer separation.

Loading docks are also a much more diverse workplace today than in years past with both male and female operators. This trend is seeing more emphasis placed on ergonomic issues associated with dock equipment, specifically dock levelers. Mechanical dock levelers have traditionally been the most popular on the dock. However, they are more labor intensive than more modern systems such as hydraulic or air-powered levelers. Because they require pulling of chains to raise the deck and operators must walk the ramp down to position it for loading, the risk of back strain and other injuries is much higher with mechanically activated levelers. Push-button operation, such as with hydraulic and air-powered systems, reduces the strain on dock operators and provides quicker cycle times and higher efficiency.

The high volume and speed of the traffic on and around the dock also increases the risk of accidents and injuries. In many facilities where maximizing the use of space is critical, forklifts often maneuver product in close proximity of an open dock door and risk rolling off the dock. An effective means of preventing such an accident is the use of a vertical barrier extending from the lip of the dock leveler.

The Kelley aFX-S is an air-powered dock leveler with a 5 inches solid structural steel barrier capable of withstanding the impact of a fully loaded 10,000-lb. forklift at 4 mph. The aFX-S maintains a constant steel barrier above and below dock to protect against accidental roll-off. To service low trailers in end load situations, the ramp can be lowered to a fully supported below dock level position without fully extending the lip, while still maintaining a constant vertical barrier to prevent the front wheels from rolling off the dock. Simple push-button controls and a high-volume, low-pressure air bag lifting system provide unequaled performance advantages that result in reduced operating costs and greater dock productivity and safety.

One of the most critical safety devices used on the dock is the trailer restraint. A mechanical or powered trailer restraint combined with an interior/exterior light communication system provides the best defense against the most common causes of loading dock accidents: trailer creep, trailer walk and premature departure. Through the natural course of loading or unloading a trailer, the force of the forklift moving in and out of the trailer can cause the trailer to "creep" away from the dock. When fork trucks enter air-ride suspension trailers the effect of the air dumping out of the suspension can cause the trailer wheels to lurch or "walk" away from the dock in an elliptical motion. Premature departure occurs when the truck driver mistakenly pulls away from the dock before loading/unloading is complete. Trailer restraints can be activated manually or automatically depending on the application. The Kelley STAR2 Restraint is a manually activated restraint that maintains a secure lock on the trailer's rear impact guard and provides positive communication to the forklift operator and truck driver throughout loading operations.

Integrating the controls for all dock equipment into a single control panel can achieve the most significant cost savings for the loading dock. Locating all controls and accessories into one integrated panel reduces the number of primary power runs, eliminates miles of wire conduits by tying everything into a single drop and significant saves on the labor costs associated with wiring individual controls. Integrated Control Panels also provide space savings, growth for future dock equipment upgrades and additions and custom interlocking of all dock equipment. Centralizing equipment controls also promote safety by providing the ability to sequence the operation so they operate in a particular order. For instance the dock leveler will not function unless the trailer restraint is engaged.


SPX Dock Products,

1612 Hutton Drive, Suite 140, Carrollton, TX 75006