New Hitachi Hydraulic Excavators for Mining
Hitachi recently introduced new versions for two of its mining-class hydraulic exca-vators—the EX5600-6 and the EX2600-6. Both -6 models feature bucket capaci-ty increases compared with the -5 ver-sions, and also offer claimed productivity improvements ranging from 17% in the backhoe version of the EX5600-6 to 12% for the shovel version; and from 13% in the EX2600-6’s backhoe configuration to 4% for the shovel version. Hitachi said it has shortened the reach of the EX5600-6 backhoe front attachment and boosted engine output, resulting in higher produc-tivity with cycle times equivalent to the -5 version. Front-shovel bucket capacity for the larger EX5600 has been increased as well, from 27 m 3 (35.5 yd 3 ) to 28 m 3 (38 yd 3 ). In addition, hydraulic pump output has been increased by 10% through a change in the pump drive gear ratio, pro-viding higher hydraulic flow rate at the same pressure. Other related improve-ments include a new design and manufac-turing process for the machine’s hydraulic oil cooler. Fan speed has been increased to provide additional cooling capacity. The EX5600-6 is powered by a Cummins diesel similar to that used in the -5 ver-sion, but with increased horsepower. The basic configuration of the -5’s cab is retained, but LED lighting has been adopted for longer life and less heat gen-eration. Interior features include an air suspension seat and low-effort short-throw levers with electric fly-by-wire, along with optional provisions for extreme operating conditions and optional digital interface with major mine management systems. Bucket capacity for the EX2600-6 backhoe version has been increased from 15 m 3 (19.6 yd 3 ) to 17 m 3 (22.2 yd 3 ), and as with the EX5600-6, the reach of the backhoe front attachment has been shortened and engine output boosted to achieve higher productivity with cycle times equivalent to the previ-ous version. Radiator and oil cooling per-formance have been increased through a changeover to a single 60-in. (1,524-mm) fan from the previous model’s two smaller fans. The EX2600-6 also offers the improved hydraulic pump output per-formance and improved hydraulic oil cool-er design included in its larger sibling. The -6 version also provides a new exterior walkway near the right rear and across the counterweight for easier access to key areas.