THE unusual request that two walking floors of a double walking floor B-train must be able to operate in tandem as well as independently did not faze NZH technical manager, who came up with a fast, tidy answer.

Chas Kelly Transport Tasmania briefed Barker Trailer Ltd to build the double walking floor B-train, to be used to cart woodchips. Tasmanian Volvo dealers CJD Equipment had to supply Chas Kelly with the Volvo prime mover, which was specced with very specific hydraulic power output capacity requirements. “Each walking floor would need an independent hydraulic flow of 110 litres/minute at 250bar pressure, or 3625psi, to operate. Calculations showed we needed 120hp to drive the pumps that would, in turn, each power a walking floor.

“Our problem was space constraints…the way the gearbox was set up, there wasn’t room for two pumps,” says Chas Kelly workshop manager, Chris Strickland. Les says the Volvo prime mover has only one PTO outlet and the team, including Bendigo-based W McCulloch and Son, had to figure out how to drive two pumps from it: “The answer we came up with was to use NZH’s Hydrocar 85VB dual-output PTO. It mounts to the back of the prime mover’s transmission and has two outputs, allowing us to mount two pumps.”

Les adds, “An added feature of the 85VB is that it allows torque delivery of up to 800 Newton metres from each output, more than enough to operate the system.” Chris is satisfied with the outcome: “At the moment it’s working fine and hasn’t given us one bit of trouble,” he says.