Split face blocks made of concrete have already been popular in garden and landscape construction in English-speaking countries such as North America, England, parts of Scandinavia and Australia for a long time. For some time now, the amount of aged masonry units used has also been increasing in continental Europe and others countries of the world. As far as the machine technology is concerned, a combination of splitting machine interacting with a tumbling system for artificial aging is used for this purpose. The result is a visual appearance of blocks with irregular edges as well as abrasions and scratches at the split face, thus showing a finished split face masonry in a „natural look“.
When aging in a tumbling operation, a considerably increased number of rejects is inevitable, in particular, if larger and more filigree masonry units are concerned. In addition, it is quite time-consuming to sort multi-size blocks after the tumbling operation and to get them back to the proper cubing pattern. So far, this technological process demanded high physical strain from the workers when manually sorting the masonry blocks with some of them having a considerable weight. Alternative systems furnished with handling equipment, which are presently available, require large floor spaces and are wear- and cost-intensive. Moreover, the artificially aged look does not even come close to resembling that achieved by tumbling, which means it appears rather mechanical.
New operating principle
The Snake Tumbler is a newly developed and patented principle of KBH to be attached to the splitting machine which convinces by simplicity, compactness and fastness. The principle allows aging of all 12 block edges to be processed in one single operating step at once.
For the aging process, the multi-size or single-size blocks are fed to the Snake Tumbler immediately after the splitting process. In the following cubing process, the blocks are packed together according to the appropriate split faces - concave and convex split faces are packetized accordingly in this proc-ess. This builds stable block cubes preventing unwanted markings or imprints on the split face. Now, packaging of the finished blocks without pallets is also easily possible.
The quick change system of the aging unit allows an easy and quick change of type. The operating principle of the Snake Tumbler not only enables regular masonry blocks of similar edge lengths to be aged but also such with varying edge lengths in one cycle. In this way, the manufacturer is in the position to offer multi-size blocks in one block cube. Extending the range of products and changing from one product to another is also easy and quick. This is complemented with additional features for controlled scratches and abrasions on the split face.
Small space requirement and zero rejects
In summary, it can be said that the most important feature of the Snake Tumbler is the fact that it creates an aged appearance of masonry units similar to the aging in an original tumbling operation. The operating principle and the look remain the same; consequently a product layer with split faces all-around needs to be processed only once in the Snake Tumbler. Any adjustment is possible ranging from slightly up to very intensive aging which however does not require elaborate and output reducing additional devices and turning devices. Furthermore, cleaning the system can be done in an easy and fast way. Dust occurring during the process is effectively absorbed by a dust collection system connected to the noise and dust protection.
The powerful version of the system allows cycle times of 15-18 seconds per product layer even at a very low noise level and dust-free. The Snake Tumbler is operating fully automated requiring just one person for monitoring the operating processes. Another economic factor in favor of the aging system is the fact that the reject rate is almost zero. In spite of its enormous diversity, the Snake Tumbler covers a floor space of just 15m², this means a maximum of 40m² for the entire system including all necessary transportation routes from and to the system.
Field-tested in the own factory
As also usual for other innovations so far, KBH have installed the first Snake Tumbler in one of their own concrete block factories and brought it to perfection in everyday operation. This procedure allows them to try and test the equipment under real life conditions and to make use of the knowledge gained from the prototype for a steady series production readiness of the machines and plants of KBH shortly.
The Snake Tumbler of KBH probably is the system with the lowest wear and tear all over the world in this field of application. A few movable parts, rugged technology and simplest mechanical principles enable easy maintenance and repair.