What:

Calibration is essential to the operation of your mixer, whether it is brand new or has been in service for years. During the calibration process, there are several detailed procedures that take place. In order for the machine to know how much of each material is necessary to achieve your desired mix design, it must first know how much material it can manipulate at various speeds. To “teach” these ratios to the computer, it is necessary to measure a sample of material after a certain distance or time frame, and input that fixed point to the computer. Once the computer knows how much of each material it is moving at a variable rate of speed or time, it can then modify those variables to produce a perfect mix that is accurate and trustworthy!

That sounds very technical. It can be overwhelming to understand how everything works. Even the most seasoned operator can have issues with comprehending exactly what is going on behind the scenes. It’s a bit easier to imagine that the mix design is like a recipe, and the computer is like a chef. The calibration process teaches the computer (or chef) what size each of the measuring cups are.

Why:

Without a precise calibration, your machine will not be accurate. If you are inserting too much water into your mix unknowingly, the mix will obviously come out wet and your customer will be unhappy. However, much larger problems can occur when it comes to cement content or admixture levels. If your customer requests a 32 MPa mix and your machine is too far out of spec, they could end up with a lower or even higher rating. Both options are not ideal, as the job may need to be re-worked, or you will be wasting material. Mix designs that call for a very specific quantity of materials require that quantity to be measured correctly. A proper and regular calibration will ensure that this remains constant.

When:

There are a number of situations when a calibration is necessary:

1. A new material is added or changed:

Even if it’s a comparable material, there is always a slight difference. Quality of aggregates can vary depending on which quarry they come from, how long they have been sitting dormant, what the water content is, and more. All aggregates must be calibrated to provide a perfect measurement.

2. Initial calibration:

When a machine is first delivered, all materials must be calibrated. Without any tuning or measurement, you will not be able to pour. All aggregates, cementitious materials, water, admixtures, and color systems must be set up properly to perform and output your mix designs.

3. Semi-Annually:

Manufacturer recommendation for calibration is semi-annually. This ensures that the information on your truck’s computer or Batchpro system stays up-to-date, and your mix designs continue to perform properly.

4. After major component replacement:

If a large component is repaired or updated, this can affect the current calibration on the machine. Changing parts that deliver material can directly affect output. Consider calibration after performing maintenance and upgrades.

5. As required by customers or regulatory bodies:

Some customers or associations you may be part of may require a calibration before starting certain projects, or in a certain time frame. Be aware of the requirements, and make sure you are prepared to have a calibration done or perform it yourself if possible.