Pentalift has developed a comprehensive dock-design-slide-presentation (multipage document providing general dock design and consideration items) that can be found on our website.
Careful consideration should be given to all aspects when designing an efficient and safe loading dock. Below are the basic aspects of Loading Dock Design to consider.
Operation of Dock Leveler:
Dock levelers are available in mechanical, air powered (air bag) or fully hydraulic operation. Mechanical dock levelers suit a wide range of applications and are the lowest cost initial purchase price of the three choices. Hydraulic dock levelers provide the highest level of safety, performance and versatility. They can be interlocked with other equipment such as vehicle restraints, inflatable dock shelters, and overhead doors. They require the least amount of ongoing maintenance. Air powered (air bag) dock levelers fall in the middle of mechanical and hydraulic dock levelers with respect to initial cost to purchase and ongoing maintenance costs.
Dock Leveler Capacity:
Mechanical dock levelers are available in 25-30-35-40-45 and 50,000 lb capacities. Hydraulic dock levelers are available 25-30-35-40-45-50-60-80-100,000 lb capacities as standard. Hydraulic dock levelers can be built with higher capacities to suit unique application requirements. Refer to link Understanding capacities for detailed information.
Width of Dock Leveler Platform
There are three common platform widths 6’ wide, 6.5′ wide and 7′ wide, nominal. 7’ wide platform provides the best access for loading / unloading side-by-side pallets at the back of the trailer.
Length of Dock Leveler Platform
There are three common platform lengths 6′ long, 8’ long and 10’ long, (nominal). 8’ long is most popular platform length. Longer lengths are available to accommodate exceptionally high/low dock heights reducing the angle of incline/decline.
Dock levelers are designed to accommodate truck and trailer beds that arrive at the facility with heights that are different than the dock height of the facility. The dock leveler deck assembly pivots and rests at an angle to accommodate the variance in the truck or trailer bed height. In doing this dock leveler accommodates truck and trailer beds that are both above and below the loading dock floor height.
It is important to manage the extent of this compensation for the difference to a reasonable and desirable level. Factors that determine reasonable and desirable levels include but are not limited to the following:
- The length of the dock leveler deck assembly. The longer the dock leveler deck assembly is the better it will be for accommodating dimensional differences in the truck / trailer bed heights relative to the load dock height. For example, all other conditions being equal, an 8ft long dock leveler deck assembly accommodates a greater height differences than 6ft long dock leveler deck assembly. The longer deck assembly simply reduces the angle of incline that the loading / unloading equipment (IE fork lift or pump truck) have to drive up and down as they go in and out of the truck / trailer.
- The type of loading / unloading equipment being used at the loading dock. For example a gas powered fork lift truck will generally have more power and larger wheels to accommodate larger angles of incline than an electrically powered pallet truck or a manually pushed pallet truck or cart.
- For obvious reasons, larger inclines create more wear and tear on equipment that is powered driven and has brakes.
- Larger inclines can result impact loads applied to the dock leveler as the fork lift hits the inclined dock leveler assembly and this can overload the leveler and result in damage to the dock leveler.
- Large inclines can create safety concerns due to possible run away loads. This is particularly true for manually propelled pump trucks or carts. As well, large inclines can make it onerous to push the same equipment up the inclines.
- Consideration of these factors should be made at the time the loading dock is designed.
- These factors should also be considered whenever changes to the factors listed above change at the loading dock.
There are 3 standard dock leveler lip lengths 16”, 18” and 20” long. Ideally the lip should project 12” beyond the face of the dock bumpers. 16” lip length is standard with a 4” projection dock bumper.
Stump-out from Mechanical Fallsafe:
It is common for mechanical or air actuated dock levelers to be supplied with mechanical fall safe legs. When the dock leveler is above floor level the fall safe legs are intended to stop a loaded dock leveler from going below level in the event that the dock leveler becomes unsupported during the loading / unloading operations. While somewhat addressing the intended concern, the fall safe legs can create other concerns that occur much more frequently than the unsupported dock leveler condition that the mechanical fall safe legs are intended to address. Refer to link Stumpout – Mechanical Fallsafe Legs for detailed information.
Weatherseal is available to minimize energy transfer between the closed dock leveler platform and the outside environment.
Our Primary Goal is to engineer and build the best loading dock products to ensure the ultimate in user safety and product reliability. Please Contact a Pentalift sales representative to discuss your application requirements.