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　　Cranes are mainly divided into four categories, which are bridge type cranes, boom type cranes, light and small lifting equipment, and mobile cranes. The following is a detailed introduction of these four categories of cranes:

　　Bridge type crane. Including beam and bridge cranes, the main feature of this type of crane is that they have beams, beams bearing.

　　Boom type crane. Including tower cranes, mobile cranes (such as car cranes), gantry cranes, etc., the main feature of this type of crane is that they have telescopic boom, boom bearing.

　　Light and small lifting equipment. Such as jack, pneumatic hoist, electric hoist, etc., this kind of lifting equipment is small in size, light in weight and easy to use.

　　Mobile crane. Such as truck crane, tire crane, etc., the main feature of this type of crane is that they can move and are suitable for different work locations.