betonnière

A betonnière, also known as a cement mixer, is a device that homogeneously combines cement, aggregate such as sand or gravel, and water to form concrete. Betonnières are essential in construction for producing concrete on-site or in smaller batches for specific projects. They range in size and complexity from portable electric mixers for DIY tasks to large industrial machines found on construction sites.

The fundamental principle behind a betonnière is the rotation of a drum. Inside the drum, paddles or blades are attached to the inner surface. As the drum rotates, these paddles lift the materials and then drop them, facilitating thorough mixing. Different types of betonnières exist. The most common is the drum mixer, which can be either of the tilting drum or non-tilting drum variety. Tilting drum mixers are typically used for smaller batches and allow for easy pouring. Non-tilting drum mixers are often larger and require a separate mechanism for discharging the mixed concrete. Another type is the pan mixer, which uses a stationary pan and rotating paddles to mix the ingredients.

The operation of a betonnière involves adding the dry ingredients first, followed by water, and allowing the rotation to mix them into a consistent slurry. The speed of rotation and the design of the paddles are crucial for achieving a uniform mix. Over-mixing can lead to the segregation of aggregates, while under-mixing results in an inconsistent product. Betonnières are powered by electric motors or internal combustion engines, depending on their size and application. They are a cornerstone of modern construction, enabling efficient and reliable concrete production.