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Don’t Let Unsaleables Break Your Supply Chain

How clearing the path between dock and trailer can reduce product and profit loss By Walt Swietlik, Rite-Hite Corporation Whether it's frozen dinners or canned goods, product somehow has to make it to market unharmed. In every industry, however, a certain percentage of all products end up discarded because of expiration, contamination or, most commonly, physical damage.

How clearing the path between dock and trailer can reduce product and profit loss

By Walt Swietlik, Rite-Hite Corporation

Whether it's frozen dinners or canned goods, product somehow has to make it to market unharmed. In every industry, however, a certain percentage of all products end up discarded because of expiration, contamination or, most commonly, physical damage. In food and beverage products, for example, the cost of damaged products (unsaleables) is a major industry concern. According to "2006 Unsaleables Benchmark Report," released by the Grocery Manufacturers Association and the Food Marketing Institute, unsaleables cost the average consumer packaged goods company 1.05 percent of annual sales (as much as $2.05 billion).
        Regardless of what kind of food or beverage products your company makes and/or ships, product damage is too expensive to tolerate. Fortunately, much of the damage can be traced back to distribution procedures and environment - which means it can be prevented. While procedures are basically a slave to the environment, the shipping and receiving environment is something that can be changed quickly to prevent lost goods.

Damage in the MTZ

Though the path from manufacturer to end-user is typically hundreds of miles long, the most treacherous stretch of travel for most products is within the material transfer zone (MTZ) - the area from the loading dock drive approach into and across the shipping/receiving area.
        Many instances of expensive product damage and/or contamination can be avoided in the MTZ, and profits regained, simply by making sure that product is loaded on and off trailers without being spilled, crushed or subjected to inclement weather. It seems simple, but unless shipping/receiving areas are precisely designed and equipped to match dock openings with trailers and their loads, product damage is inevitable.
        Dock positioning and design, load configuration, dock equipment, forklift interaction and trailer design are all vulnerabilities in the MTZ. If not configured appropriately, interruption of material flow and consistent product damage will result.

Inadequate access

     As trailer dimensions have increased, shippers have reconfigured loads to take advantage of increased payload space. For that reason, modern shipping trends and corresponding trailer design are largely responsible for the mismatch at the dock that can lead to product damage.
        For example, 102-inch-wide trailers enable 48-inch-by-40-inch Grocery Manufacturer Association (GMA) pallets to be pin wheeled - turned 90 degrees - to increase the payload. If pallets are stacked two-high and double pin wheeled (two rows side by side), the total payload can increase by as many as 12 pallets. This eliminates empty space along the trailer sides and creates room for several more pallets, thus increasing payload and reducing shipping costs.
        Often, these trailers arrive at loading docks filled from wall to wall with a full eight feet of product - from floor to ceiling - all the way to the rear sill. What's more, they are generally below the typical 48-inch dock height, as trailers with lower bed heights have increased interior space to allow even more product to be loaded. This is great for shipping efficiency, but causes problems as it becomes extremely difficult to smoothly and efficiently access and maneuver product off the trailer.
        The first few pallets of a fully cubed, below-dock trailer are difficult for workers or forklifts to reach, due to interference from bumpers or pit walls surrounding standard six or seven-foot-wide levelers. Product can be crushed on the way out as it knocks against these obstructions. Even after the first pallets are removed, loads can still be damaged as the forklift impacts the interfering pit wall as it's backing out of the trailer.
        When below-dock, fully loaded trailers must be serviced. The best loading/unloading conditions can be achieved through the use of extra-wide (8 feet, 6 inches) dock levelers or ground-based truck levelers to eliminate pit wall interference.
        Another source of access problems that can lead to product damage, as well as building and door damage, stems from the mismatch between dock openings themselves and the trailers that must be serviced. Modern trailer sizes have outgrown many existing loading dock openings so that walls, door tracks and foam dock seals protrude into the trailer. This, once again, leads to restricted access to loads as well as troublesome interferences as the forklift attempts to maneuver loads.
             Considering the size of today's trailers, any dry facility handling full trailer loads should be outfitted with dock openings of at least 9 by 10 feet. Refrigerated facilities should have minimum door sizes of 8 feet, 6 inches by 9 feet. All dock openings should also be equipped with shelters or combination seal/shelters that provide full, unobstructed access to loads without compromising an efficient seal.

Water & moisture

     Dock seals and shelters are typically considered for their ability to keep cold or hot weather out and controlled temperatures in. But moisture can be even more damaging. Just a few drops of moisture can rust metal, ruin electronics and destroy paper-based packaging and products. Food and beverage products are also susceptible to contamination, as water on any one product in a pallet will often make the whole load unusable. In addition, penetrating rain, snow, sleet and moist wind can lead to wet or icy floors that are hazardous to personnel and equipment.    
             The most common form of water damage occurs when rain or melting snow flows down the back of the trailer onto the trailer bed and dock leveler. Unless the water is blocked with a tight fitting seal, it can fall on product and personnel moving in or out of the trailer. Typical dock seal head pads, head curtains and traditional shelters are generally not able to prevent this "funnel effect" problem from occurring. However, using a weighted top-sealing sealing system that seals tightly across the full width of the trailer roof can prevent water from flowing into the dock, which keeps product, equipment and personnel dry and protected.

Rough transition

Once obstruction from small doors, doorway intrusions and bad weather has been eliminated, a smooth transition from dock to trailer - through the MTZ - must be addressed. As a lift truck enters a trailer, fragile loads can be damaged due to dock shock and trailer drop.
        Dock shock and trailer drop are terms used to describe unsafe situations that occur during the process of loading and unloading semi-trailers. "Dock shock" describes jarring that occurs when a lift truck crosses between the warehouse floor and the trailer bed due to the bumps and gaps that exist on traditional dock levelers. "Trailer drop" describes vertical trailer bed movement, or "drop," that occurs with the weight of lift trucks traveling in and out of trailers.
        To address dock shock, some specially engineered levelers feature a constant radius rear hinge to create a smooth transition between the warehouse floor and the leveler, as well as a two-point crown control on the front lip hinge of the leveler to smooth out the transition from the leveler to the truck bed. For tackling trailer drop issues, a new category of vehicle restraints is now available. The restraint supports the rear of the trailer during the loading and unloading process, which minimizes both vertical and horizontal trailer movement.
        Another situation that needs to be addressed at the dock involves high-slope applications, or otherwise problematic transitions for lift trucks. The best way to address the problem is with extra-long hydraulic levelers or ground-level hydraulic truck leveling systems. The longer levelers - up to 12 feet - drastically decrease the angle of the bridge into the trailer by extending the trailer to warehouse transition area. Because extra long dock levelers are also typically extra wide, this configuration allows full access to wide trailers, which eliminates pit wall and bumper obstructions for efficient below dock service. Truck levelers, on the other hand, can eliminate slope altogether by adjusting the height and angle of the trailer bed to match that of the dock.

Finding solutions

     When product damage is a problem at any food or beverage manufacturing or distribution location, profits are needlessly lost. An investigation of the shipping and receiving procedures throughout the supply chain should be the immediate response. Where are materials coming from and how are they loaded? What are the types and sizes of trailers being used?
        A professional well versed with the issues surrounding the MTZ can determine if the source of product damage can be narrowed down to shipping and receiving procedures. If so, this crucial area can be designed and equipped to handle loads quickly, efficiently and without damage. A dock design expert can also demonstrate how an initial investment in redesign will be quickly overshadowed by reduced product damage and regained profits.