The main technical parameters of the bridge crane are lifting capacity, span, lifting height, running speed, lifting speed, working type and power on duration of the motor, etc
Lifting height: the distance between the upper limit position and the lower limit position of the crane’s spreader or grabbing device (such as grab and electromagnetic suction cup) is called the lifting height of the crane, in meters (m).
Span: the span of the bridge crane refers to the distance between the wheel centerlines at both ends of the main beam of the crane, that is, the distance between the crane track centerlines, in meters (m).
Lifting capacity: also known as rated lifting capacity, refers to the actual maximum allowable lifting capacity of the crane, in tons (T).
The lifting capacity of bridge crane is 5, 10 (single hook), 15 / 3, 20 / 5, 30 / 5, 50 / l0, 75 / 20, 100 / 20, 125 / 20, 150 / 30, 200 / 30, 250 / 30t (double hook), etc.
According to the lifting capacity, the bridge crane can be divided into three grades: small crane of 5-10t, medium crane of 10-50t and heavy crane of more than 50t.
Working type: the working type of crane is determined by its load rate and busy degree, which can be divided into four grades: light grade, medium grade, heavy grade and extra heavy grade.
1.Light grade: Operation speed is low, use times are few, full load opportunities are few, power on duration is 15%. It is used in the workplace which is not tense and heavy. Such as crane used for installation and maintenance in hydro-power station and power plant.
2.Medium grade: It often works under different loads, with medium speed and not too heavy work. The power on duration is 25%, such as the crane used in general machining workshop and assembly workshop.
3.Heavy grade: Heavy work, often working under heavy load, with a power on duration of 40%, such as cranes used in metallurgical and casting workshops.
4.Extra heavy grade: Often working under rated lifting capacity,the work is very busy, and the power on duration is 60%, such as metallurgical bridge crane.