1. Types and requirements of wheels
1) Classified by purpose. Track-travel wheels are usually used for wheels that travel on the lower flange of crane I-beam; semi-circular groove pulley wheels are used for cable cranes.
2) Classified according to the presence or absence of rims. Double-rim wheels are widely used in cranes, and are often used for traveling wheels of rail-mounted cranes such as bridge and gantry cranes. Trolley wheels with a diameter greater than 500mm also use double-rim wheels; single-rim wheels are generally used for smaller gauges And on the running wheel of a trolley with a diameter of less than 500mm, the side with the rim should be installed on the outside of the trolley track (because the main beam is bent outward); the wheel without rim is not blocked by the rim, and the wheel is easy to derail, so the use range is limited. Installed on the single-girder crane trolley, the rimless wheels are divided into horizontal anti-rollers and vertical anti-rollers, which are important components used to balance the eccentric moment of the trolley.
3) Classified by wheel tread. Cylindrical wheels are mostly used for driven wheels and can also be used for driving wheels; conical wheels usually have a taper of 1:10, which can automatically straighten and compensate for the adverse effects of vehicle body skew. The big end of the wheel should be placed on the inner side of the crane track; The drum-shaped wheels and treads are arc-shaped, which are mainly used for electric hoist suspension trolleys and circular track cranes, which have the effect of reducing additional female force and wear.
4) Classified by contact with the top of the crane track. According to the difference between the wheel tread and the top of the crane track, it can be divided into line contact and point contact (Figure 2-3). The contact between the wheel with cylindrical tread and the flat-top track is line contact, and the force of the line contact is better; the contact between the wheel with cylindrical or conical tread and the dome track is point contact, which is commonly used in crane structures. It’s a point of contact.