Screw-type air compressor structure of a unique design, a compact, stylish appearance, high efficiency, small energy consumption, low noise characteristics and long life, is a smart environment-friendly pro.
[pdf] In this study, the fracture of piston for rock drill produced from case hardening steel is investigated. In order to study the causes of the fracture, specimens prepared from the damaged pistons were subject.
[pdf] Rugged, long-lasting design makes these amazing drill rigs as dependable as they are powerful. Dual rotary drill rigs have two rotary drive mechanisms, an upper rotary head and a high torque lower drive unit.
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