With its uniform machine direction yarn structure Atrojet has far greater surface contact than conventional bases. This leads to more even pressure transmission at the press nip resulting in very steady dewatering and even CD profiles.
In addition to these two modern press felt design groups the classically woven, respectively laminated base weave felt designs, belong to the Heimbach assortment too. Even though the existing product spectrum is sophisticated Heimbach keeps on improving its existing product lines and developing new products.
Atrojet is one of the latest developments which is an innovating new press felt design combining the advantages of multi-axial and non-woven technology. With the multi-axial non-woven technology, the product managers can meet the particular requirements of press felt positions even better. The specific quality of Atrojet is the structure of the base inside, which is, facing the paper side, and consists of a unique non-woven layer. That layer of yarns is made of machine direction yarns only which results in great strength, evenness and smoothness of the base facing the paper side. The machine direction (MD) yarn structure is arranged in diagonal direction which is the characteristic multi-axial angle improving collapse resistance by increasing crossing points of all yarns. Broad flexibility is given by the fact that the non-woven paper side layer can consist of different ply twist yarns as well as different yarn diameters and flexible yarn count.
The evenness and uniformity from inside the felt provides smooth felt surfaces through high contact area. The homogeneous and high contact area of Atrojet base is superior among press felt technologies. Homogeneous compact felts are important features for tissue felt application regarding even pressure transmission at the press nip which is key for even dewatering and even CD profiles of the paper. The roll side base of Atrojet felts is made of multi-axial arranged components and are selected as per individual request concerning void volume, mechanical strength etc. and in context of the individual requirements of the position e.g. one or two nip positions or shoe press position, uhle boxes & vacuum rolls involved. A typical tissue machine could present the performance of a press felt in the proper light. Mileage of > 100,000 km while passing about 6 million nip cycles and handling > 50,000 m³ of water are normal requirements for a tissue felt. In addition, the level of performance is expected to be at steady high level all along the service life of a felt. Modern press felt designs from Heimbach are high-tech products which meet these requirements. In case that process parameters vary very little the felt design can be fine-tuned to its maximum performance under those standard conditions. As more the process parameters do vary as more challenging can be the designing to get an adaptable felt design.
Heimbach clothings are used in the production of a wide range of paper grades and types