Heavy lifting
Pallets are widely used by most industries because they fit three basic materials-handling principles:
A wide variety of hand and powered equipment has been developed to handle pallets. Selection should be made based on the size of your operation, the frequency of deliveries, the type of materials handled and the distance the materials must be moved. The following are the most common equipment available and some selection criteria.
This is the lowest-cost pallet mover. It is pulled by a walking operator. The truck is backed under a pallet and a hydraulic or mechanical mechanism raises the pallet a few inches off the ground. The large wheels allow a load as large as 6,000 pounds to be moved with a force of only 75 pounds. A paved surface is needed.
Pallet trucks are good for moving materials around the headhouse or unloading trucks if you have a dock that is at truck floor level. Choose one that has ball-bearing wheels, rear rollers that will fit the common pallets that are delivered to you and a capacity for the heaviest loads you need to move. If you move a lot of materials over longer distances more than 300 feet, then a forklift is a better option.
Also known as straddle trucks, these will unload pallets or other heavy objects off a truck where a dock is not available. Foot-powered and battery-powered units are available with capacities of several tons. With stacking heights of up to 5 feet, they are good in storage areas for bulbs, nursery stock or supplies. Look for units that have adjustable fork spacing, large wheels (8 inches diameter or larger) and a capacity for the heaviest pallet.
Forklifts are a better choice where materials have to be transported longer distances. They can be powered by gasoline, diesel, propane or battery. Propane- or battery-powered units are best for inside a building. Gasoline- and diesel-powered units are best if the grade traversed is greater than 10%.
Select one that will carry the largest expected load. Most materials, such as growing media, and containers are relatively light. Even the largest cart loaded with flats or pots is less than a ton. For most applications, a capacity of 3,000 to 4,000 pounds is adequate. Fork truck capacities stated by the manufacturer are generally the maximum safe load.
Many attachments can be fitted to a forklift. Those common in greenhouse and nursery operations include materials bucket, adjustable tine forks to pick up and space containers on the floor, clamps to handle boxes or bales, snowplow and crane.
A low-cost solution to getting a forklift is to add forks to an existing piece of power equipment such as the front-end loader of a tractor or skid steer loader. For the generally light pallet loads found in the greenhouse business, a front-end loader attachment can work well. The load that can be carried will depend on the size and weight of the tractor and the front-end strength and tire size.
A better choice might be to purchase a forklift that attaches to the three-point hitch. With rear mounting a heavier load can be carried. Attachment to the tractor takes only a few minutes.
OSHA regulations require training for anyone operating a powered forklift or other vehicle that can push, pull, lift, stack or tier material. This standard does not apply to vehicles used for earth-moving or over-the-road hauling. Many grower organizations provide training courses to meet this requirement.
This device has become increasingly popular in greenhouses and nurseries. Originally designed for the sod and grass industry, the Spider is a forklift that can be towed to the job or carried on the rear of a truck or trailer bed. Using its own hydraulic system, it can load itself. Once on location, it has a capacity of 3,500 pounds. Featuring large flotation tires, it can work in rough or muddy conditions.
John is an agricultural engineer, an emeritus extension professor at the University of Connecticut and a regular contributor to Greenhouse Management. He is an author, consultant and certified technical service provider doing greenhouse energy audits for USDA grant programs in New England. [email protected]
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