At the World of Concrete Tuesday Liebherr showed for the first time its new 50-meter truck-mounted concrete pump, the 50 M5 XXT. The pump truck’s five section boom reaches to 161 feet vertically and 146 feet horizontally.
For moving the material, the M5 XXT offers four pump unit options with outputs from 138 to 167 square meters per hour. The four pivoting outriggers are secured directly to the distributor boom pedal which directs the weight from the boom directly into the outriggers with no flexing of the body of the truck. Liebherr kept the weight down and increased stability with a newly designed boom pedestal. The slewing ring and drive are proprietary Liebherr components.
The front and rear outriggers on the M5 XXT pivot on the same point. “This gives you a ton of flexibility as you set up,” says Liebherr’s Clinton Nichols. “Setting up on tight jobsites is very easy to do. You gain more than 180 degrees working range on the boom,” he says.
The American market wants a heavy machine that they know will last 20 years and be structurally sound and safe on the jobsite, says Nichols. For this reason the all-German made Liebherr M5 XXT is built with rugged components and simplified electronics.
“We have very few electronics on it, just relays and a sealed computer board,” says Nichols. “We have a bypass mode built into the pump so you can bypass the proximity switches or the computer and you can keep pumping without having to get into the inside of the control panel. The operator flips a switch, he continues pumping and finishes the job,” he says.
The hydraulics are also simplified Nichols says. “It uses a proven open loop design for the hydraulic system. This allows us to use the hydraulic oil efficiently. We do not have an accumulator circuit like most of our competitors. We use the main pump to drive it, taking a hydraulic pump out of the system and eliminating failure, and we are able to send more pressure to shift the S-tube which translates into being able to pump harsher, rockier mixes,” he says.
Maintenance is also simplified with the use of components common to all the Liebherr concrete pumps. “All the wear parts: material cylinders, mud cups, S-tube and carbide wear parts are all interchangeable, so if you’re a fleet owner there’s no need to stock multiple size parts. They’re all the same,” says Nichols. The concrete pistons and mud cups are a one piece design and easy to take out, he adds
The pump is load sensitive as well, so it is not shifting at the same pressure all the time, says Nichols. It shifts with just enough pressure based on the concrete. “It’s not wearing the backend out unnecessarily if you’re pumping an easier mix or a mix with a higher slump which translates into longer wear part use,” he says.
In the transport position the truck measures around 39 feet long. The company offers a wide range of options on the M5 XXT including additional storage compartments, a modular water tank and additional steps on the left side. An integral, high pressure cleaner makes cleaning easier and a pneumatic hose end air cuff prevents concrete from running out when the pump unit is stopped.