Komatsu's new tool carrier

Komatsu is in the final stages of the development of two versions of its PC800LC-8 that have been factory-designed with additional auxiliary hydraulic circuits and safety valves to be able to mount large hydraulic attachments, one designed specifically for use with breakers and the other able to mount large demolition attachments up to 8.5 tonnes in weight.

Komatsu had identified that a number of customers for 50 to 90 tonne carriers had the machines modified by local dealers or other specialists to carry such tools in the demolition and mining sectors. These were one-off solutions developed for a single application with the machine unique to that customer. With a view to ensuring it was meeting its customer’s needs, Komatsu began a PC800LC development programme to establish the best compromise between providing the required performance allied to meeting its own quality standards without interfering with manufacturing efficiency and lead times.

The breaker model features accumulator installations of both sides of the boom to reduce peak pressure and improve reliability, new boom and arm piping, a filter installation in the boom foot area and a direct return line to the tank for low back pressure, with breaker activation through a pedal in the cab. The tool carrier version carries a new long boom and arm and the piping required for two hydraulic circuits and a drain line, an unloader valve to reduce return back pressure and accumulators in the circuit for breaker operation and shear break through.

Mode of operation can be selected electrically. Breaker mode configures the circuit for low back pressure in the return side of the circuit. Medium flow mode allows hydraulic flow of up to 450 litres/min for use with attachments that do not demand the full 900 litres/min to give better controllability, with tool rotation controlled by the on-off buttons on the levers and breaker or crusher actuation again via a floor mounted pedal.

When D&Ri saw the machine, it was undergoing final testing at an Able UK site near Doncaster, which provided ideal conditions for the work.