How Do They Weight Food For Packaging?

By Author: Larry Tang
Total Articles: 512
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Within an industrial application, it is often desirable to keep track of the weight of an item as it changes over time. The simplest example of this is a tank of liquid or liquefied gas that is used in an industrial process. The material may be an adhesive that is dispensed onto a substrate. Or it may be a coating or paint that is sprayed on an object. Alternatively, multiple ingredients are often fed into a mixing container, and the amount in each container must be recorded. Other applications include a gas that is used during the etching process of a semiconductor wafer or resist or masking material that is used in the same procedure. Within the food industry, a wide variety of liquids, powders or other materials are mixed together in fixed recipes.

The best way to actually determine the amount of material in a tank, carton, pail or other container is simply to weigh it with an industrial scale. This scale may be in the form of a large floor scale or drum scale to accept a drum or tank. For smaller containers, a platform scale may be suitable. Even lighter loads may be accurately weighed on digital bench scales and ...
... precision scales.

Generally, the electronic scale must be designed for the specific material being weighed and the environment in which the weighing process will take place. A general purpose floor scale with a steel platform and stainless steel load cells is suitable for the general industrial workplace. But it might be necessary to use a stainless steel platform if there is a corrosive atmosphere. Similarly, a drum scale may have an aluminum platform for most situations. But if there are highly reactive ingredients, a stainless steel platform may be indicated.

While an industrial process is proceeding, the weight of the material that is being consumed or produced, or the weight of the material remaining to be processed, may need to be logged for future analysis. There are many sophisticated and expensive systems available for this purpose. The most common is to run a communication cable from a central computer to each industrial scale. A standard communication protocol, such as RS-232, may transfer weight data from the scale to the computer. This method is often not suitable for a number of reasons. The scale may be at a location that is quite distant from the recording computer. It has also been calculated that the cost of running cables to industrial equipment is very high. There are numerous electrical codes that must be followed. Wiring may have to be routed through existing ceilings, walls or other obstacles. The cost of connection may be much higher than the cost of the digital scales.

If there are a number of scales in the same location, networking the scales will often be a suitable method for reducing this cost significantly. In this case, a multi-drop protocol, such as RS-485 may be employed. A single cable is routed from scale to scale, and then continues on to the central data collection device. Usually, an adaptor is used to convert the RS-485 data into a standard that the computer can accept, such as USB (Universal Serial Bus).

Often, though, it is not necessary to monitor the weight in real time. What is required is a logged history of the usage of the material over a period of time. Arlyn Scales offers a much simpler and much less expensive method for logging this data from their line of industrial scales. Their entire line of scales, including parts counting scales, floor scales, lab scales, bench scales, drum scales and floor scales may be obtained with an optional USB memory stick data logger. An industry standard thumb drive is plugged into the optional USB data logging port. The scale can be programmed to send weight data to the memory stick on a timed basis that may vary from once an hour or more, to as fast as a number of times a second. Or, a key on the front panel may be pushed by the scale operator every time a frame of data must be recorded. An internal clock system will also record the time and date of that measurement frame.

USB memory sticks are very inexpensive. A 2 Gbyte capacity device can cost as little as $12. This will have the ability to record hundreds of thousands of data points, and the time associated with it. At any time, the data sticks may be removed from the scale and brought to any computer. When plugged into a USB port on the computer, the collected data can be entered into an Excel spreadsheet or Access database file. Standard data analysis tools may be employed to examine the scale data.
Arlyn Scales' goal is to provide clients with superiority in equipment and service unrivaled for industrial scales. For almost 30 years Arlyn has manufactured top of the line industrial weighing equipment with an accent on quality, accuracy, advanced technology and durability. From Livestock, Alpaca and Llama Scales to Ultra Precision Scales and everything in between, Arlyn Scales has it all.