A few years ago I heard that an expert wanted to prepare a product standard on “dynamic crane scales”, but for some reason it was not introduced. In fact, according to the application of the crane scale will be simply positioned as a nonautomatic scale, there are many practical problems can not be explained clearly.
A dynamic crane scale should be a crane scale that weighs while the load is lifting and moving at the same time during the lifting process. It is difficult to distinguish between dynamic weighing and static weighing if they are simply defined as such. Because the “dynamic weighing” means: the load being weighed and the scale carrier there is a relative movement, while the crane scale for weighing between the two no relative movement, only in many crane scale use occasions, due to the hanging equipment of their own original. Since the object to be weighed is seldom at rest for a short period of time, even if the value is read, it is still slightly different from the value at rest.
Crane scales include hook scales , crane-type crane scales , gantry (bridge) crane scales. And crane type crane scales are roughly weighing trolley type, wire rope reel weighing type, fixed pulley weighing type and so on. Hook head crane scale is the load cell installed directly on the hook head of the lifting equipment, this structural form of crane scale, most of the combination of a variety of load cells. Gantry (bridge) crane scales, most of which are of the wire rope reel weighing type.
When we look at a scale product such as a crane scale alone, it can be completely defined as a “non-automatic scale”. However, if we look at the whole lifting system, whether it is a shore bridge crane or gantry system in a harbor, or an overhead crane system in an industrial or mining enterprise, all of them are inseparable from the long wire rope connection, and all of them are observing the weighed items during the lifting and moving process weight value. It is because of this weighing method and the wire rope that this creates two problems for the use of crane scales:
（1） In the lifting process, under the action of the equipment lifting force and the gravity of the goods, the wire rope suspending the crane scale will inevitably stretch and contraction of the movement, and sometimes the lifting equipment suspending the crane scale is also trembling. It is in this elastic effect, the crane scale can not reach the result of the value of the weighing in a timely manner.
（2） In general, the crane scale is used outdoors, will be affected by the environment, especially the crane scale used on the port terminal, by the wind will produce oscillation of the crane scale will be more to promote the trembling of the wire rope, but also affect the impact of not in time to get the weighing results of the factors.
Post time: Sep-04-2023