Loading Dock Solutions

Loading docks are the first and last contact at any facility. It’s the place where supplies first arrive and the place from where shipments leave. With today’s modern, fast-paced loading docks, selecting and properly installing the best leveler for the job plays a major role in safety and productivity for your clients.
Creating safe and efficient bridges between facilities and the trucks and trailers that pull up to them is no easy task. With so many different kinds of dock levelers available today — in such a wide variety of sizes, shapes and mounting styles — choosing the right one can be more complicated than ever.
The reason there are so many choices in dock levelers has to do with the large variety of freight, vehicles, frequency of use and loading conditions. These different operations place different demands on a dock leveler, so it is important to make sure that the leveler you choose matches your individual client’s requirements.

Use considerations

The first thing to consider is where and how the dock leveler will be used. Is it a replacement, a retrofit or new construction? What types and variations of vehicles will be unloading and loading? What are the space limitations? Are environmental control and security prime considerations?
Budget or space restrictions may unduly influence the decision. Having all the information on the types of levelers helps tremendously in analyzing your client’s needs, and sorting out the many options and their resultant tradeoffs. Consider the following factors:

Types of levelers

Edge-of-dock
These levelers are mounted to the outside of the face of the loading dock. As such, they’re the most economical and typically the easiest levelers to install. However, their drawbacks include limited size and weight capacities.
These levelers are commonly used for truck terminal applications where a specific trailer is being serviced regularly. They can typically only accommodate trucks and trailers that are five inches above or below where the leveler is mounted. If you have a refrigerated trailer or ocean container, which tend to be higher, they may not be able to reach.

Pit-mounted
These offer greater capacities and options that suit more demanding cross-docking applications. Pit-mounted levelers typically have greater working and service ranges, and adaptability over edge-of-dock levelers because they offer more space above and below the leveler. One caveat to this type is that the dock door rests on the leveler and may not provide the best seal — a factor to consider for cold-storage applications.

Recessed or vertical-storing
This type is for applications where temperature control is a concern. These levelers are better at keeping the elements and pests out and the temperature in. They also offer better security because the trailer can fully back up to a dock while the door is closed, and the leveler is not put down until there is a fully sealed environment.

Operation

There are three basic types of dock leveler operation:

Mechanical
These are typically spring-biased upwards, with a hold-down mechanism. The most common type relies on the dock operator using a pull chain to release the leveler from the parked position and extend the lip. The operator then walks onto the platform, using body weight to lower the leveler onto the trailer bed. The concerns with mechanical levelers are that they are not very ergonomic and present many opportunities for injury. They also require a high amount of maintenance and adjustments.

Hydraulic
These levelers use an electric pump that drives a hydraulic cylinder to automatically engage them, and are typically controlled with a remote switch mounted on a wall near the dock. Hydraulic levelers are the best choice for higher capacity, smoother and quieter operation, ease-of-use and reduced maintenance and overall lower lifetime operating costs. They can also provide a wide range of safety features, such as fail-safe protection.

Power-assisted
These mechanical levelers use push-button controls to power counter-balanced springs or airbags that force the leveler up; gravity then brings the leveler into position on the truck bed. Pneumatic types typically incorporate a single push-button control with a high-volume, low-pressure air activation system.

Capacity

Leveler capacity simply means that the selected leveler has the structural strength to handle the weight, speed and frequency of use of your material handling equipment.
Selecting the proper capacity for the leveler can be confusing due to the variables that must be addressed. To ensure proper capacity selection, consider these factors: gross vehicle weight (vehicle + load), maximum height differential between trailer and dock (operating angle of dock), forklift speed and tire type, how many shifts at the facility, and how many trailers will be serviced per dock, per day.
Capacity also means taking into account how many trailers will be coming in and out and how long they will be occupying the docks. Layout of the facility, traffic-flow patterns and construction techniques also need to be considered when factoring capacity.

Length

Material handling equipment used for loading and offloading has grade operating limitations, so it is important to consider this when determining the right length of dock leveler. As a rule of thumb, the greater the difference in height between dock and trailer bed, the longer your levelers should be to avoid steep and dangerous slopes with unusually high or low vehicles. In addition, wider levelers provide better access, more maneuvering room for lift trucks and greater flexibility for clients.

Costs

Units range in price from under a thousand dollars for edge-of-dock levelers to several thousand for large-capacity hydraulic levelers. Initial cost, however, is just part of the picture when evaluating levelers.
Pit construction costs can vary significantly depending on the type of leveler. If selecting a pit-mounted leveler, one should carefully consider the time and money advantages of using prefabricated pour-in pans integrated with the dock leveler rather than labor-intensive pit forming.
Anticipated maintenance and repair costs are also vital factors. Consider the accessibility of components for servicing. Look for simplicity of design. Check the overall quality of construction, including under-deck supports, and consider the frequency of required maintenance, especially between hydraulic and mechanical models. Levelers can vary widely on these points, which all contribute to the overall lifetime ownership cost of the unit.

Additional Factors

The dock leveler makes up only one piece of a loading dock. Consideration must also be given to dock safety, communications, operator environment, and energy conservation.
Dock safety
In a busy shipping area, there can be up to 100 opportunities a day, per single loading dock, for serious mishaps to occur. A common cause of serious accidents is a worker or lift truck falling off the end of a dock. Vehicle restraints effectively prevent vehicle creep and unscheduled truck departures. Dock guards further protect against lift trucks from inadvertently running off empty levelers or into dock doors.
Driver Communication Systems
A combination of signal lights, controls, and signage advises both vehicle drivers and dock attendants of safe/unsafe and park/depart conditions. High-visibility safety systems are available for automated, integrated, and manual control situations.
Dock seals and shelters
A good system provides protection from the outside elements for products, packaging, equipment, and employees, as well as reduces pilfering at the loading bay. It will also greatly improve energy conservation, internal temperature control, and worker comfort. Many configurations are available from basic types of compression dock seals, standard dock shelters, and inflatable seals to hybrid dock seal/shelter/inflatable designs.

Dock levelers have evolved into much more than just a ramp between the loading dock and the transporter vehicle. Today, they are an integrated component of an entire loading-dock system that allows for the safe and efficient loading and unloading of goods to and from transporter vehicles using forklifts or pallet trucks.

Steve Greco is a frequent speaker and author of articles on loading docks and the director of international sales and marketing for Blue Giant, a Brampton, Ontario-based manufacturer and distributor of dock equipment, ground-level dock lifts, dock-safety products and industrial trucks. To reach him call 800.668.7078 or visit www.bluegiant.com.