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By George Leposky |
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At sea or on the highway, the sheer size and weight of the larger conveyance limit its maneuverability. It can’t start or stop as fast, and it requires a much wider turning radius. Also, in each case, the operator must deal with issues of cargo securement—to prevent containers from falling off a ship’s deck, or a bulldozer from falling off a trailer.
Like a ship’s captain, the driver of a big rig for hauling heavy construction equipment must receive proper training and obtain a special license. Licensure demonstrates that the individual has met a government agency’s minimum standards of qualification to operate the conveyance—but a license alone is no substitute for experience. “I’ve had just three drivers over the past 25 years for my low-bed trailer,” says Warren Gomes Jr., vice president of Warren E. Gomes Excavating Inc. in Rio Vista, CA. “You get surprises when you put guys into a low-bed who don’t regularly drive it. The more experienced they are, the fewer surprises there will be. They have an intuitive knowledge of weights and heights, how the truck pulls, and how the trailer reacts.” Gomes emphasizes, though, that even an experienced driver can run into problems if he is driving an inappropriate rig. The truck and trailer must be right for each other. Gomes has two low-bed trailers, an eight-wheeler from Kalyn Siebert of Gatesville, TX, a subsidiary of Heil Trailer International; and a 16-wheeler from Harley Murray Inc. in Stockton, CA, which does business as Murray Trailers and Murray Trucking. The firm initially built pads for natural gas wells, but now digs trenches and installs storm sewer and water pipes for housing developments. When Gomes began hauling a 75,000-pound excavator that exceeds the Siebert’s legal weight limit, he purchased the larger trailer. “When we went to the 16-tire low-bed, we needed a specific truck to pull it, to take advantage of the load advantage,” he says. “The two have got to be compatible. You can’t just buy a new low-bed and hook it up behind your old truck if the truck isn’t ‘spec’d’ enough to pull the low-bed. “Having a trailer you can haul 44 tons on doesn’t help you much without the right truck. We need to put up to 20,000 pounds on the front axle of the truck, and we need the right-size rear end and wheelbase. Just by having the wrong front axle, we could lose up to 8,000 pounds of payload. We also had to buy the trailer with a 10-foot gooseneck so it would slide up farther on the truck and keep the rig level.” Loading and Unloading
“We use trailers with hydraulic detachable goosenecks,” Armstrong says. “You dump the air in the suspension, set the front of the trailer down with its detachable neck, and drive away. Then you flip down the two folding loading ramps and walk the machines on from the front of the trailer.” H&R Paving Inc. in Miami, FL, owns about 80 pieces of heavy equipment. Raul Gonzalez, the firm’s president, says its pavers and rollers typically go up and down ramps at the rear of a trailer, but a 25-ton milling machine loads onto the front of a low-bed trailer with a detachable gooseneck. Brian Weseman, president of Towmaster Trailers Inc. in Litchfield, MN, recommends using an angle-iron beavertail to gain maximum traction while loading. “A wood beavertail tends to be slipperier,” he says. “Bulldozers, excavators, and rubber-tired backhoes will get far superior traction on an angle-iron beavertail than on a wood beavertail or ramp, but you need wood if you have a roller. A smooth roller won’t climb an angle-iron beavertail.” Driving heavy construction equipment on and off a trailer can be a delicate operation, especially when the terrain isn’t level and flat. Sometimes a site is so uneven that an adjacent roadway must be commandeered for loading and unloading, despite the disruption of traffic. “When you’re loading and unloading, a major concern is to make sure you’re not doing it on a side hill,” cautions Weseman. “Try to minimize the side angle so the equipment doesn’t do the crappie flop—tip over sideways like a fish.” Loading and unloading in wet, muddy conditions causes other concerns. “The softer the ground, the farther into it your trailer is liable to sink,” Armstrong notes. Noise during the unloading process also can bring grief to a driver. In cities with noise ordinances prohibiting nocturnal construction noise, delivery of a large piece of equipment outside the permitted hours can prompt complaints and attract the police. Tie-Down and Stowage The regulations specify in considerable detail how to accomplish this for various kinds of loads, including heavy equipment (weighing more than 10,000 pounds) with wheels or crawler tracks. Such equipment must be restrained from movement in any direction using at least four tie-downs, each attached as near as possible to the front and rear of the vehicle. Before tie-down, hydraulic shovels and other accessory equipment must be completely lowered and secured to the vehicle, and articulated vehicles must be restrained so they won’t move around in transit. Tie-down is “the thing that scares me the most,” says Gonzalez at H&R Paving. “I tell my people to secure the equipment good before they leave, and inspect it to make sure it’s really tight. If you drop one of those pieces of equipment, you’ve got problems. All it takes is for somebody to forget a chain, and you’ll have a big catastrophe. “When we pull equipment out of our own yard, more than one person looks at it. On a job site, when we’re loading to bring the equipment back again, we have to rely on the driver doing his job.” The FMCSA regulations list the standards to which steel strapping, chain, webbing, wire rope, and cordage must conform. Knots aren’t allowed; tie-downs must be secured in some other manner so they won’t come loose during the haul. On a trailer equipped with rub rails, the tie-downs must be located inboard of the rub rails whenever practicable. Edge protection is required to prevent abrasion, cutting, and crushing where a tie-down touches the cargo. The regulations also prohibit the use of damaged or weakened securement devices. Even without such official prompting, a wise driver will always examine tie-down devices for fatigue, damage, cracks, or missing parts; check safety chains and hooks for wear; and verify the tightness of all hanger bolts, deck bolts, and U-bolts before moving a load. Tires and Wheel Lug
Nuts “Check your tire pressures weekly,” advises the Towmaster Trailers Inc. Web site. “Tires can seep a couple of pounds of air pressure a week. The number one cause of tire failure is improper inflation. It can also cause your trailer to dog track or sway. Pressure should be checked while the tire is cold before operation. Also check for tire wear and wear patterns. Once a pattern has been established it’s almost impossible to stop. It’s important to catch it before it becomes established.” Also check a trailer’s lug nuts often and, when necessary, tighten them to the proper torque. “Wheel lug nuts should be checked and re-torqued after the first 10 miles, 25 miles and again at 50 miles,” says the Towmaster Web site. “Follow this procedure every time a wheel is removed. If the wheel has been run with loose lug nuts it will wallow out the holes where the studs come through and the only fix for this is a new wheel.” Other Pre-Hauling
Preparations
Drive Slow and Easy Once underway, drivers of these large rigs need a different perspective on highway conditions than the average motorist. Gonzalez wants his drivers to watch for and be sensitive to road conditions ahead. “With low-beds,” he says, “you have to be very careful not to buy the very low ones. They have such a low profile that they hit the pavement sometimes when there’s a dip in the road, or they hit the ground and get stuck when they go over a curb. You buy low-beds because they are easy to load the equipment onto, but with deficiencies in the road they cause problems.” Low-beds constructed with protruding metal underneath also have the potential to catch on railroad tracks. A driver hauling such a trailer should be aware of this risk. Gonzalez encourages his drivers to limit their speed, for increased safety and longer brake life, even if they get traffic tickets for going too slow on expressways where the minimum speed is 40 mph. “I’d rather have a ticket for going too slow than for going too fast,” he says. Drivers must be alert for the unpredictable actions of other motorists. Gomes recounts an incident in which a car pulled out in front of a driver hauling an empty low-bed trailer. “The driver swerved to the side to avoid hitting the car, and the low-bed came to a stop spanning a canal beside the road. We unhooked the truck, brought in a crane, pulled the low-bed up, and set it on the road. The low-bed was fine.” Weseman urges drivers to be sensitive to clearance issues. “Avoid surprises,” he advises. “Know what your overall height is, and make sure you can clear underneath bridges. Just because a bridge is marked at a certain height doesn’t mean it’s actually that high. A road crew may have come through with another layer of tar, so now that bridge marked 13 feet, 6 inches, is actually 13 feet, 2 inches.” Understand Antilock
Brakes The US Department of Transportation has required ABSs on truck tractors with air brakes built since March 1, 1997; on trailers built on or after March 1, 1998; and on hydraulically braked trucks built since March 1, 1999. Some older vehicles have been retrofitted with ABSs. To determine whether a vehicle has an ABS, look for a yellow ABS malfunction lamp on the truck’s instrument panel and on the left front or rear corner of the trailer. (If you’re pulling an older trailer that lacks an ABS lamp, look underneath the trailer to see if wheel speed sensor wires run from the back of the brakes to an electronic control unit.) The ABS malfunction lamp may flicker at startup for a bulb check, or stay on until the truck speed exceeds 5 mph. If it remains on after that, the system may not be working at every ABS-equipped wheel. Under those circumstances, the brakes will continue to function under normal driving conditions, but the ABS should be serviced as soon as possible. The Trucking Research Institute and the Federal Highway Administration’s Office of Motor Carrier and Highway Safety have published a handy explanatory booklet, Truck Drivers Guide to Antilock Braking Systems (available online at www.fmcsa.dot.gov/español/english/pdfs/abs_book.htm). The booklet explains that if a rig has an ABS on all axles, the driver can apply the brakes fully in an emergency stop. Otherwise, it says, “When only the tractor has ABS, you should be able to maintain steering control and there is less chance of jackknifing. But keep your eye on the trailer and let up on the brakes (if you can safely do so) if it begins to swing out. “When only the trailer has ABS, the trailer is less likely to swing out, but if you lose steering control or start a tractor jackknife, let up on the brakes (if you can safely do so) until you gain control.” For older vehicles without antilock brakes, the risk of brakes locking up is greatest when the rig has a light load or is empty, and the consequences can be costly even if no accident results. “Anytime you get in a lightened load situation, lock an axle, and slide the tires, you go out of compliance and have to change the tires,” Gomes explains. “That can cost $200 to $285 a tire, and you lose eight of them at a time.” Communication Helps,
Too To avoid such surprises, a wise driver will request the details of each assignment in writing, along with documentation of any permits that the job may require. Such paperwork helps ensure that the driver will do the right thing in the right place at the right time, and that any permitting questions the authorities raise en route can be resolved quickly. Miami-based construction-industry writer George Leposky is a frequent contributor to Grading & Excavation Contractor. GEC - September/October 2005 |
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