Scale equipment

CONVEYOR BELT SCALES

Process Automation manufactures a variety of belt scales in acknowledgement of our customers varied requirements. The precision available from these scales not only depends on the model type but also (mostly) on the application into which they are to be installed. Our computer-aided analysis of the application(s), allows us to recommend the scale model best suited to meet the application and performance requirements. Process Automation manufactures 14 different scale models.

The factors that influence the material down-force are the belt stiffness and belt tension – it is critical to understand that the higher the belt tension and the stiffer the belt, the longer the weighframe has to be. It is for this reason that for ROM belts we install our Accuweigh Six Scale to ensure that the material down-force is optimally transferred to the scale, and not suspended within in the belt itself – in other words the belt has to sag over the weigh area.

For shorter conveyors and lower tension applications or for feed control application such as your Mill Feed Scales one can consider shorter weighframed scales (Dual idler and Four Idler), whilst for very low tension applications one can even consider a Single Idler scale.

What is also very important to understand is that over time the in-accuracy will change/vary, and that regular maintenance will be required.

Sustainability – to ensure the conveyor scale remains within, or close to the achieved accuracy, we define certain acceptable limits known as the Allowable Error (AE) - the error that the user does not want to exceed.

The ultimate value of the belt scale depends on it being In Calibration as close as possible to 100 % of the operating time. Poor calibration maintenance results in mistrust in the scale’s readings – a perception which is often difficult to reverse, diminishing the value of the scale.

In order to determine the maintenance interval required, our unique As Found Error (AFE) maintenance program must be followed.

The AFE maintenance program makes use of statistical methods to ensure that the measurement systems are operating to the desired precision, and indicating problems long before they would otherwise have been noticed.

Typically the AFE will have a “Gaussian” or “Normal” Distribution.

It is important therefore that one specify not only the AE but also the probability that this error will be within certain limits. This is specified at 1σ or 2σ (one or two sigma).

By selecting an Allowable Error and a Probability (x-Sigma), the you will be assured of being able to reliably predict the performance of his scale over time (both past and into the future) – provided that the scale is checked and adjusted within the Maintenance Interval.

WEIGHT FEEDERS

Process Automation manufactures a large range of Weigh Feeders to the clients specic needs and specication. Each Weigh Feeder is custom designed and built to exacting standards and for the precise application thereby avoiding the need for ‘shoe horning’ a standard design to approximate the weighing requirement.

 

From 500 Kg/h	to 2000 (plus) t/h

LOAD CELLS

From 7 Kg	to 2000 (plus) t
Process Automation has designed unique 7kg weighing systems/asks that operate in harsh industrial conditions