Why are all CST's Belt Weighers custom designed and built?

All CST's belt weighers are custom designed and built so that they will meet the customers performance needs in their actual application.

There are some commonly held ideas about belt weighers in the industry, that, for example, a four idler belt scale is a 0.25% accurate device, regardless of the type of material, the belt tension, and a host of other site factors which have a significant effect on weigher accuracy. That this is plainly not true is reflected by the general poor opinion of belt weighing accuracy held by most in the bulk handling industry, who have been taken in by this kind of marketing.

It would be well accepted that most conveyors are different to each other, each has a different length, different lift, different capacity, belt speed, profile and so on. As a result each conveyor has a unique belt tension environment and presents often radically different environments in which a belt scale would be expected to operate.

Belt scales are extremely application specific, that is, it is not possible to consider the accuracy of a belt scale except in the context of the actual conveyor which it is to be built into and the actual duty which it is to experience in that conveyor. This is why CST use their engineering knowledge to design a specific belt scale for each application, so that the performance of the belt scale can be as required by the user rather than hoping that the theoretical accuracy offered by some standard 'off the shelf' equipment manufacturer will be able to replicated on site.

As previously mentioned, it is plainly not true that a four idler belt scale is a 0.25% device and a two idler belt scale is a 0.5% device. In fact, here at CST we promote a different wisdom, we say that you need 'Different Belt Weighers in each Different Conveyor to achieve the same accuracy.

An accuracy of 0.5% is commonly requested for a site which has many belt weighers such as a typical Coal Preparation Plant (CPP). In reality the customer would probably prefer 0.25% however the 0.5% choice is made as a practical cost compromise.

The plant will however have many different conveyors with a variety of lifts, lengths, widths, capacity and so on, each presenting a different belt weighing challenge. Would it not be ideal if every belt weigher on the site would work to the same level of confidence, in other words, if each belt weigher would always produce true results with an error no greater than 0.5% of the actual flow, down to 20% of capacity. CST's design process is not unlike the concept of the Reynolds Number which is used in pipe flow calculations (http://en.wikipedia.org/wiki/Reynolds_number. The reynolds number allows the designer to say 'these flows are alike' even though they are happening under very different conditions. Therefore using our design process, CST is able to design all of the belt scales on a site to achieve the desired accuracy, to the same level of confidence. Of course, in doing this, CST is designing a specific solution in each case and as a result, CST will design different belt scales for each different conveyor to achieve the same performance.

CST have automated the design for each of their products. The conveyor environment data is fed into the design program and the outputs are all the design characteristics of the belt scale and at the same time a pricing calculation is performed. Additionally, at the same time, the description of the product with pricing is produced, is transferred to the written proposal for the customer and becomes the basis of our offer. CST have been at the forefront of computer technology for some time and have been emailing pdf versions of our offers to customers rather than using paper offers for more than 10 years at this time. Due to our Computer Aided Design process, we are able to send fully detailed offers, detailing our custom solution for your specific conveyor in a very timely manner. We look forward to the possibility of providing this service for you. See our belt scale inquiry questionnaire.

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