Launching Komatsu 951XC

A final logging harvester that combines power and productivity with agility and excellent climbing ability. And a harvester that is also a perfect match for the C164 head. This is one way of describing the new eight-wheeled harvester from Komatsu Forest, the third addition to their range of eight-wheeled harvesters specially designed for demanding conditions.

The Komatsu 951XC is a new harvester for final logging in steep terrain and on soft ground. The eight-wheel design, combined with the stable Komatsu concept, ensures a machine with great stability, excellent manoeuvrability, and low ground pressure. The Komatsu 951XC is also optimised for use with the Komatsu C164 – a harvester head specially designed for logging large trees – although naturally it works just as well with a range of other heads.

For demanding conditions

The Komatsu 951XC is part of Komatsu Forest's product series of machines specially designed for challenging conditions.

"Now we have a complete range of eight-wheeled machines, specially designed for demanding conditions", Joakim Johansson, Product Manager Harvesters at Komatsu Forest says.

Compact yet strong

The machine design is much like that of the Komatsu 951, although there are some differences. The Komatsu 951XC has the same wheel size as the 931XC, lending the machine a more compact design and giving the 951XC a total machine length that is shorter than that of the Komatsu 951.

The Komatsu 951XC has 242 kN of underlying tractive force and unique interaction between engine, control system and power transmission. The hydrostatic transmission enables engine power to be fully utilised, providing considerable advantages in difficult terrain as well as excellent climbing ability. This is much due to the machine's large hydrostatic pump, which can maintain higher speeds at high tractive forces.

“What is special about the 951XC is that it combines the strength of a 951 with an extremely compact design. Since it has about the same dimensions as the 931XC it can be used in denser stands,” Joakim explains.

951XC is also equipped with hub reductions. They provide an advantage when working in challenging conditions, such as steep, snowy, or wet terrain, as they increase the life of the bogie and thereby machine reliability.

The Komatsu 951XC has new working hydraulics to better utilise the diesel engine. The new hydraulics also provide faster feeding from start to maximum speed and allow the saw motor to work even more efficiently.

“The new working hydraulics contribute to a feeling of an even stronger engine according to the test operators that have been working with 951XC,” Joakim states.

Although the working hydraulics are new, in all other respects the Komatsu 951XC shares the same proven design as other Komatsu harvesters, meaning 3PS.

“This enables several crane and head functions to be used simultaneously with retained maximum hydraulic power, all thanks to the machine's hydraulic power coordination,” Joakim continues.

Powerful crane

All Komatsu harvesters are equipped with parallel cranes, this has been the case since 1999. With the Komatsu Forest design concept, the lifting booms and outer booms are linked, thereby eliminating an entire aspect of crane control. This concept simplifies crane operation by ensuring that the head is always in level regardless of crane cycle stage. The parallel crane is also cleverly designed to be fast in its outward movements, when the head is unloaded, and powerful in its return movements, when the head is heavily loaded.

Compared to the 951, the Komatsu 951XC has a significantly shorter distance from the centre of the crane to the front wheels. This creates a larger working area in front of the machine, that enables the operator to work at shorter reaches.

“The new larger working area in front of the machine means more powerful crane movements. And for those who equipes their machines with Smart Crane they get an even more easily manoeuvred crane with excellent precision,” Joakim explains.

Operator environment

The Komatsu 951XC, just like all other Komatsu harvesters, features a high-performance operator environment. Examples of the many advantages include the spacious cab, good visibility and comfortable cab climate.

Thanks to the machine’s stability and levelling cab, the operator is always seated level without the need to stretch and strain to maintain a good seating position. The 951XC is, as all Komatsu harvesters, based on the tried-and-tested Komatsu concept that offers favourable weight distribution and has a low centre of gravity. In addition, the eight-wheeled XC series harvesters have a double oscillating bogie on the rear frame giving the machines completely unique handling characteristics.

“Our double oscillating bogie on the rear frame is an innovation of which we’re very proud. As well as increasing stability by lowering the machine’s centre of gravity, the machine follows irregularities in the terrain in a forgiving manner while delivering excellent manoeuvrability in challenging terrain conditions,” Joakim ends.

The work to develop a new machine is a massive team effort. Before a new machine model is launched prototypes are thoroughly tested first with Komatsu’s own test operators and then by contractors working in environments suitable for the specific machine model. One of the contractors, Henrik Lysebäck at Lysebäcks Skogsentreprenad, tested a prototype of the 951XC in the fall of 2022 and concludes the test like this;

“The 951XC is a good machine, stable and comfortable to operate. It is a machine you can trust, and you feel secure working at a long reach. This is definitely a machine I would like to continue to work with.”