Underground haul trucks working with LHDs are used on a large scale for horizontal hauling in the copper mines of KGHM in Poland including the Lubin, Polkowice and Rudna operations. Most of the population of underground trucks are machines with a capacity of up to 25 t and are produced by internal company KGHM Zanam. The latest products include the TB series of trucks: the CB4-20TB (20 t) and CB4-24TB (23.4 t).

These are modern machines, equipped with KGHM’s own monitoring system that acquires many operational parameters according to the KGHM data acquisition standard which have been developed in close cooperation with the machine operators. Thanks to the data from the onboard monitoring system, these machines have been equipped with the a Lock-up system, which is closely related to the operation of the gearbox.

The Lock-up function on the CB4-20TB truck is automatically activated by the digital transmission controller under certain conditions. For specified operating ranges, the gearbox mechanically blocks the hydraulic torque converter. KGHM says this action has improved the efficiency of the transmission, which translates into lower fuel consumption, reduced exhaust emissions, reduced gearbox oil temperature and a reduction of heat emission by the converter, which further improves the efficiency of engine braking, reducing the load on the braking system, thus prolonging the lifespan of the brakes and the safety of the operators.

Today five of 30 KGHM CB4-20TB trucks have the Lock-up function but KGHM hopes that further research and positive results will mean it will be applied on many more TB series machines.