From liquid wax to candle -
the stirring process as a key process

Our latest case study is about the most cozy light in the world. Especially now, as we approach Christmas, we like to remember the warm glow of a candle and one or two find a place on our tables and shelves.

Our customer, the Brothers of Mercy Saffig, produces candles by hand. The wax is heated, colors and essential oils are added, and then the wax is poured into jars. But what is the big challenge in candle pouring?

Unwanted air pockets

Stefan Sausen, Head of Production, explains: „The special feature [of wax stirring (editor's note)] is to ensure stirring without air entrapment. And we can do this with a wide range of filling levels in the wax pot.“

Air pockets are not only a problem with waxes, but also with lacquers, for example, when it comes to further processing. With waxes, air inclusions are not desirable from a purely visual point of view. In addition, the customer wants to buy 100% homogeneous wax. The air pockets therefore considerably reduce the quality of the product. For the Brothers of Mercy, however, the biggest problem lies elsewhere:

Essential oils are added to the candles. If the air pockets rise to the surface of the heated wax and burst there, the essential oils spread at the place of production and not just to the customer.

The stirring process as a key process

Once the air pockets have formed, it is very time-consuming to get rid of them again. Therefore, the only option is to prevent them from forming in the first place. And this is where the secret lies in the upstream stirring process: only gentle, constant stirring that is adapted to the fill level in the container and the medium prevents air from being drawn in from the oil surface. The wax is removed via an outlet tap at the bottom of the stirring container.

Since using the PTM agitator on a traverse, the quality of the wax has been impeccable and there have been no more air pockets. The essential oils are also no longer released during the production process. Our customer can adjust the stirring behavior directly on the agitator at any time and adapt it to changing conditions.