water pump shaft material

First, the classification of drilling RIGS:
1, according to the use of the address is not the same, the drill can be divided into underground and open air two categories. According to the presence or absence of traveling structure, the drilling rig can be divided into self-propelled type and non-self-propelled type. There are many open-pit drilling RIGS in China, most of which are self-propelled.
2, according to the aperture is not the same, the drill can be divided into light drilling rig, medium drilling rig, heavy drilling rig.

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