High rise Cat eliminates compactor

By working smarter, with fewer items of plant, a New Zealand waste management company is keeping itself ahead of its competitors.

Envirowaste works right across New Zealand's waste management sector, collecting waste material, sorting it at its transfer stations and removing recyclables before transporting the remainder to its landfills.

At the transfer stations, the efficiency of Envirowaste's operation relies on achieving payload in the trucks being dispatched to landfill. Some of the company's competitors achieve this using front end loaders to push material into hoppers for compaction before loading onto trucks.

According to Richard Fenn, regional manager for Envirowaste, his company takes a different approach.

“We've found that by using an excavator with a grab we can sort the material more effectively than we could with a loader,” Fenn said. “And, as long as the operator has a good view into the truck, he can organise the loads better and achieve payloads without the need for a compactor.”

Normally good visibility of the loading process is achieved by having the work platform above the level of the truck. However, at Envirowaste's Christchurch transfer station, limited headroom prohibited the floor level from being raised, so some innovation was required.

“We really needed to get the operator up higher,” said Fenn. “Several manufacturers build excavators with hydraulically raised cabs, but that feature is generally only available on machines of 20t upwards.

“The New Zealand market just isn't big enough to justify us buying something that size,” he said, “so we approached Goughs [the country's Caterpillar distributor] about building a raised cab on a 12t Cat 312CL that would put the operator's eye level about 4.5m above the floor slab.”

There were servicing and structural issues to consider, but Goughs also had to look at safety. The cab needed safe access, and limits had to be put on the machine's operation, to take into account its higher centre of gravity.

New walkways and handrails were fitted, the bonnet was strengthened to allow the operator to walk over it and, to eliminate any risk of the machine tipping, a limit was set on the maximum depth of waste that the machine was allowed to operate on. In addition Goughs fitted a special guarding package, with beefed up belly plates, foot rails and engine compartment guarding. Goughs also needed to play a major role in training the operators to safely handle the unique machine.

The high rise 312CL brings to five the number of Cat excavators Envirowaste now has in service. The 312CL has been operating for several months now and, according to Fenn, is working exceptionally well, with the capability to shift up to 50,000t of material in a year, without the need for a compactor.