The last 20 years have seen significant consolidation in manufacturers of large scale mining machines with the emergence of the 'big four' that include Cat, Komatsu, Liebherr and Hitachi.
An example of this consolidation was the sale of Orenstein & Koppel (O&K) to Terex Mining in 1998, that was then acquired by Bucyrus International in 2010 and consumed soon after by Caterpillar Inc in 2011.
Each a formidable brand in their own right, these companies laid the foundations to the many technologies (and equipment) found in mining today. O&K's RH400 is one such machine, that since 1997 has dominated its category in size and longevity.
Known today as the Caterpillar 6090 and weighing in at a mind-boggling 1,000t's, this face shovel is a sight to behold. Albeit now yellow, it's origins are far from American, with the machine designed and manufactured by O&K in Dortmund, Germany.
It was conceived with the emergence of the 240T haul truck, where O&K felt it needed a hydraulic excavator capable of loading these trucks in three passes. Forming a cooperation committee with Syncrude (think oil sands in Canada), this digger took an incredible 18 months to produce and was in dirt by 1997. Determined as requiring a bucket in the 40 cubic meter range, O&K blessed it the RH400.
Initially fitted with Cummins K2000E engines, the first two diggers were considered underpowered.
However, in acceptance testing averaged 5,494 bank cubic yards an hour and 29 seconds per pass, a remarkable achievement in the knowledge that the bigger QSK60 and 3516B engines were to come. Even before their repowering, Syncrude was so impressed with the shovel's performance that they purchased the first four that rolled (crawled) off the production line.
Today, a far more extensive array of large hydraulic excavators exist. Despite their emergence (the likes of the Leibherr R 9800 and Hitachi's EX8000) the Caterpillar 6090 remains the largest hydraulic shovel in its class. Sporting a bucket payload of 93.6t it is an impressive machine that with its counterparts, has taken it right to the rope shovels.
With increased life spans, greater mobility and lower initial price points, these machines are increasingly becoming the 'digger of choice' for mine operators. With Cat now the maker's marque, one wonders the next evolution in store for the 6090. Could we see an upgrade of engines (or at least engine option) with the C175, only time will tell...
This article was originally published by the Components Only team in the February 2021 issue of "@ The Coal Face" magazine.Published 8 February, 2021