How to find the right machine

Identifying the most suitable quality control system for your needs is crucial to achieve the highest quality of the desired outcome and, of course, to make the most of the investment made.

Therefore, it is absolutely important to accurately identify your needs and define the operational framework of the system: a careful analysis in this preliminary phase is the key to future satisfaction.

Here is a brief guide to the elements to consider.

1. The type of desired control

The first element to evaluate in the selection phase is, of course, the desired functionality in your machine.

Is it only dynamic weighing or weight labeling as well?
Is it important to detect the presence of metal particles in the product
Will the rejection and expulsion of non-compliant products be done manually or automatically? What is the degree of reuse of the rejected product?
Do you want the packages to be classified and separated based on weight?

The answers to these questions will be the starting point for finding the ideal machine.

2. The product

Like a dress must fit the wearer's shape, the weighing system, to achieve the best performance, must be designed based on the characteristics of the products it will analyze. Evaluating shape, dimensions, weight range, packaging, and any element defining the product is essential for the correct design of the checkweigher.

Shape: A product with an unstable base, narrow base, and/or much taller than its width, or with a rounded shape, will require special considerations (such as side guides) to prevent it from falling during transport on the conveyors. On the contrary, products less prone to vibrations, with a wide and non-rounded base, won't present particular challenges.
Packaging and Packaging: Are the products being checked pre-packaged or loose? What type of packaging is involved? The accuracy requirements for weighing a bottled liquid differ significantly from counting pieces in a box.
Products that lose material: Packages like small powder sacks tend to lose some particles during transport, risking a alteration of the weighing result. This circumstance must be taken into account by the manufacturer, for example, by providing perforated belts to prevent residue accumulation and periodic recalibration of the weighing program.
Viscous or liquid products: Products like viscous liquids or loosely compact items (from paint to canned peas) are subject to movement within the package caused by vibrations during conveyance. These internal shocks alter the accuracy of the result and must be considered and minimized during the design phase.
Moisture content: Is the product wet? Is there a risk of sticking to the conveyors? The higher the friction and viscosity of the product, the greater the alterations to weighing precision when transitioning from one conveyor to another.
Weight and frequency: What weight range do the products fall into? A few grams or tens of kilograms? The design and accuracy required for the system will obviously be very different.
Speed and frequency: At what speed and frequency does the product leave the production line? The higher the conveyor speed, the lower the maximum achievable accuracy. Similarly, to avoid the simultaneous presence of multiple objects on the scale, proper spacing between products is necessary.
Metal Contamination: Is the product at risk of metal contamination during processing? Does the relevant regulations require metal particle detection checks?

In choosing the optimal system, it is also necessary to carefully evaluate the different product options you wish to operate with. While focusing on the future possibilities of your product range allows you to design a system capable of working with products of different shapes/weight ranges/dimensions than the current ones, in many cases, it may lead to the selection of a suboptimal solution in terms of accuracy in weighing the products actually in production, physical footprint, and final price.

3. Working environment

The environment in which the checkweighing system will be used will have direct effects on the system itself: evaluating its impact on the machine is one of the main tasks that the manufacturer will have to perform.

Temperature: What is the temperature in the working environment? Is it constant or subject to fluctuations? Considerable and sudden temperature variations can alter the weighing results.
Humidity and washing: Will the machine operate in a high humidity environment? Will it be subject to splashes or water jets? How will washing be carried out?
Dust and debris: Will the working environment be characterized by the presence of volatile particles? Will the machine be subject to the accumulation of residues?
Vibrations: Is the floor on which the machine will be placed subject to vibrations? Are there air currents or other sources of possible shocks?
Corrosion: Is the working environment potentially corrosive? Can the machine be subject to corrosion?

The first and most important element that the manufacturer will need to assess based on the elements just mentioned is the degree of isolation of the machine. This will be reflected in the IP code of the machine, an international system for measuring the degree of protection against the infiltration of solid particles or liquids.

Moreover, the weight control system is not an independent unit but will be integrated into the production line organically. Knowing and considering the entire line, the interactions, and the chain effects between the different elements is another key factor to optimize the performance of the analysis.

4. Certification

The machine will be used for legal trade control or only for internal use? Is MID / OIML R-51 approval required?

Community and international regulations govern the control and weighing of pre-packaged products (contained in packaging and weighed in the absence of the buyer, prepared so that the weight of the product is predetermined): for such goods, certified systems based on the minimum requirements stipulated by law will be mandatory.