Sandvik Process Systems has used ACHEMA 2012 to launch its newly developed Rotoform? 4G system, the latest generation of a system first introduced in 1980 and now widely recognised as the standard solution for granulating a wide range of chemical melts including sulphur, waxes, resins and agrochemicals.

Building on the experience gained over 30+ years and the design of a Rotoform family that now numbers 10 different models, each meeting the needs of a different sector, Sandvik has redesigned and reengineered a number of key system functions to deliver increased availability, higher productivity and improved product quality.

System enhancements include a redesigned refeed bar which simplifies operation and improves product quality, a lifting device to streamline servicing, and new bearing units that reduce maintenance requirements.

The overall principle remains the same, with a one-step melt-to-solid granulation process delivering consistently sized, free-flowing, dust-free pastilles. Molten product is fed onto a continuously running steel belt in the form of droplets. These are solidified by means of cooling water sprayed against the underside of the belt. This indirect cooling is not only highly efficient but also means no risk of cross-contamination between product and cooling water.

"The 4G model is based on the proven Sandvik Rotoform process and represents a significant step forward compared with its predecessor, the RF3000," explains Matthias Kleinhans, Managing Director of Sandvik Process Systems. "The new system enables easier operation and also reduces the servicing and maintenance requirement. This means lower running costs and an attractive ROI."

The new 4G model is fitted with a pneumatic refeed bar that is raised to the correct operating position at the touch of a button. Automatic positioning of the heated refeed bar ensures that any surplus material left on the depositor after the drops have been placed on the steel belt is forced back through a channel in the Rotoform. It is then remixed with the product and returned to the production process.