Because precast producers deliver a wide variety of concrete products, fleet managers need flexibility when it comes to unloading devices, says Darrin Cary, quality control manager at Wibert Precast in Spokane, Wash. For example, his company employs straight boom models, trolley-style swing booms, and telescoping boom trucks.
One common feature in all of these devices is that the truck crane needs to be lightweight but also have a high-load capacity, Cary says. Reach isn't always as important to precasters as it is for other crane users. “Our drivers can usually get pretty close to the unloading spot, so a long reach isn't needed as frequently,” he says.
Since getting close is a concern, producers try to match the unloading system to chassis selection. Cary likes the cab-over-chassis configuration because it's shorter, more maneuverable, and more flexible for crane placement.
Cary has found that knuckle boom cranes have certain advantages. They're lightweight and space-efficient, leaving more capacity for product. Yet they have two drawbacks. Knuckle booms can't position their load straight down and they tend to be slower than straight boom cranes.
Efficiency is another issue producers must consider when selecting a crane. Most producers opt to load the truck at the yard with forklifts. For that reason, Cary says managers should be more concerned about unloading options.
One innovation that has increased delivery safety had been the wireless remote control units. They're faster than the old cable units and the driver can be further out of harm's way, says Cary.
Stand-up control crane
Featuring an easy-reach console that moves from one operator station to the other, the series 1300H crane is a 30-ton capacity stand-up control crane that can be mounted on a three-axle truck. Pilot-operated hydraulics allow for smooth operation and precise load control. The four-section boom is available in lenghts of 69, 100, and 110 feet. National Crane Corp. 402-786-6300. www.nationalcrane.com.
Multiple boom options
The 400 series truck-mounted cranes can be fitted with four different booms with horizontal reaches from 31 to 60 feet. Other boom configurations are possible to suit almost any special requirement. Effer/North American Lifting Equipment. 330-916-6461. www.efferusa.com.
Boom truck features long outreach
The HIAB XS 422 boom truck offers up to eight hydraulic extensions and more than 68 feet of hydraulic outreach. It is available in two boom versions: a standard with four to eight hydraulic extensions for extended reach operations and a P-boom variant for big and bulky loads at close quarters. Hiab Inc. 419-482-6000. www.hiabus.com. MCPX booth #1427