(courtesy of Liebherr)
A Closer Look
In 1959 Grove brought the first rough terrain crane to market as a multi-purpose machine for use on construction sites. It became their signature product in the next few decades. Larger RT cranes have replaced the smaller crawler crane as the off-road crane of choice.
Today’s RT cranes have a hydraulic boom between 80 and 140 feet long. Most feature four-wheel drive and all-wheel steering, which increase off-road maneuverability. Capacity ranges from 30 to 130 tons.The steel used to make these cranes can withstand extreme temperatures, and the axles and superstructures can handle mud, snow and extreme terrains.
Rough on the outside though they are, the cabins can be fitted to include heating and air conditioning, which means the operator can work long shifts in comfort in even the most grueling conditions.
New Rough Terrain Crane Developments
This year, Liebherr added a series of rough-terrain cranes with the unveiling of the new LRT 1090-2.1 and LRT 1100-2.1 at Conexpo 2017. The new crane line was driven by extensive market analysis showing a demand for high capacity combined with safety and ease of operation.
The new cranes feature an outrigger monitoring system. The support status, the attachment of the ballast to the turntable and the installation of the double folding jib (including its angle adjustment) are all detected automatically, recorded to the crane controller and monitored.
The variable support base (standard on Liebherr’s rough-terrain cranes) makes each individual outrigger beam extendable. The load moment limiter calculates the maximum load capacities precisely to minimize the risk of accidents during the assembly process and when hoisting loads. As a result of the increased lifting capacities when hoisting over the supports, the cranes can hoist loads usually reserved for the next higher crane class.
Liebherr’s return to the rough terrain market is a response to increased demand for these off-road machines, particularly in North America and the Middle East.
RT Crane Benefits to Fleet Managers
Rough terrain cranes are expensive machines, but fleet managers can keep long-term costs down by properly maintaining and repairing them. Knowing when to use an RT crane (as opposed to a telehandler or crawler) is essential in ensuring long crane life.
Since it’s a smaller crane on rubber tires, RT cranes are more portable and more easily set up at the job site than the alternatives. Telehandlers don’t have the same slewing capabilities; RT cranes offer significantly more reach and capacity.
The trend toward higher capacity RT cranes in recent years lets managers lift heavy loads that once required a crawler. Handling more lifts with a single machine means huge savings in both time and money.
Another perk? Rough-terrain cranes don’t need another crane to be assembled. They can come into a job site on a truck, make quick lifts and leave—making them easy to set up as well as easy to use.
Care and Maintenance
Keeping these machines up and running, while operating costs down means adhering to the manufacturer’s recommended service schedule.
"Staying within the guidelines of your scheduled maintenance would be the top thing to keep the overall expense of the machine down,” says Jeff Dreger, director of product and customer support for cranes at Sany America. "Like certain greasing that has to be done on a boom. Check the wire rope, and the fluids and stuff in your drums. Keep proper air pressure in tires. Make sure fluids are up to spec, and that you’re changing them when you should.”
Cranes running multiple shifts a day will have different service requirements than cranes traveling long distances to do less work. Check the manufacturer’s recommendations to see how special situations may accelerate or otherwise change your service and maintenance schedules. In addition, make sure you outfit the crane with the right oils and seals–particularly when working in extreme hot and cold conditions.
Even on rocky job sites and in demanding industrial environments, today’s rough terrain cranes should give you 15, 20 or 25 years of reliable service. Some of these old warhorses are reliably performing beyond the three-decade mark.Do you want to see lower owning and operating costs and a greater return on your crane investment? With LC Crane Parts and Service on your team to provide high quality parts, repair and rebuild services, and diagnostic assistance, you can keep your RT cranes running longer, reduce down times and extend their service life.