There are many different types of scales such as the floor scales, the bench scales, the counting scales, the platform scales and the coil scales – each having their own importance in weighing things. The coil scales are used in weighing coils that have to be loaded by lift trucks or cranes. These scales can be used by themselves or incorporated into the design of already existing product lines. They are generally used for industrial purposes especially in steel mills. They are mainly used for steel coil packaging and transporting line and processing line.
The base structure of the coil scales should be able to handle the weight that has to be weighed and the weighing apparatus. The base platform should be in contact with the load cells. A minimum of one cell needs to be placed between the base portion and the platform portion. There should be a one guide to align the base and the platform. A signal should be given about the weight of the article to be weighed. The capacity and measurement accuracy of the coil scales depends largely on the different sizes and weights of the load cells which play an important part of the coil scales. The load cell overload protection should be 150 percent. It should be designed in such a way for 100% concentrated load capacity (CLC).
The coil scales can handle capacities from 20,000 lbs. to 80,000 lbs. There are coil scales that can handle heavier capacities which range from 10,000 lbs. to 100,000lbs. The weighing range is can handle 6 tons, 10 tons, 20 tons and thirty tons.
There are two types of coil scales which are used. They are:
1. Buffering steel coil scales and C type steel coil scales which are used in the packaging industry, in the end of packaging line.
2. U tunnel online transporting steel coil scales and hydraulic pressure lifting steel coil scales.
A saddle supports and weighs the coil scale. The interface has rubber which protects it from any damage to it. The main features of the coil scales are: Free floating load cell assemblies, double ended sheer beam load cells, heavy duty I-beam construction and digital weight instruments. It can also have other features attached to it like R.F. radio data transmission to far off places, scoreboards, printers and computer interfaces, CRT touch screen digital control system, removable V-deck, polyurethane protective wear pads and hydraulic lifts.
These features help in the process of weighing the coils. For this various functions have to be performed by the coil scales.
1. Software for weighing can help in the automatic weighing of the coil material, number, width, thickness, input etc. The data has to be stored and printed and can be connected to a PLC or controller.
2. It needs a durable scale board to weigh which should be highly stable. It should be designed in such a way that it can resist powerful strikes. Such a board can be custom made according to requirement.
3. They also need protection from rust and so have an oil coating which helps in protecting it from corrosion when it is stored for a long time. This oil can be removed by degreasing just before the coils are taken for delivery.
4. The coil scales need to have a very strong platform structure to withstand the load to be weighed. They also need adjustable feet. They should be anti-shock proof. The load indicators should be precise and reliable.
5. They can have flat decks, v- decks or rails for the coil transfer car weighing. They should prevent coils from rolling from the decks.
6. It requires center loaded sheer beam cells which are strong, durable and give maximum support. If side loaded, the suspension allows the platform to move, thus preventing damage to the load cells.
You can also have coil car transfer scales. These are fully electronic NTEP platform sizes from 4’6” to 20’10”. Their capacities range from 20,000 lbs. to 120,000 lbs. You can also have non- NTEP platforms.
All these specifications are necessary for coil scales to function properly and weigh coils accurately. Thus, durability and accuracy are two main considerations.