Machinery & Components
New shoe press belt has high impact strength
By Cindy Macdonald
A common reason for an unscheduled shoe press belt change is cracks. When an external object or hard paper wad hits the belt harshly it may cause a crack or a puncture hole. Sometimes the sleeve may seem intact outside, but a small crack may have generated which ultimately can lead to an oily spot in the felt, a hole in the paper, poor web moisture profiles, off-spec paper quality, sleeve delamination and eventually, an unplanned belt change.
When the material used in the belt has sufficient toughness and good impact strength, cracks can be avoided. Valmet’s belt specialists have developed a new shoe press belt, BlackBelt E, which, according to the company, has the highest impact strength of any belt currently available.
BlackBelt E (E for extreme conditions) achieves this due to its high-performance polyurethane composition which boosts impact strength against accidents.
The original BlackBelt was launched in 2008 following a year-long development project. Now, with about 500 BlackBelts sold in North America and almost 2000 BlackBelt deliveries worldwide, Valmet has a large installed base.
The development of new versions continues. BlackBelt G has triple-layer reinforcement and is designed for small diameter shoe presses. The double-layer BlackBelt F (flexible) suits applications requiring a sleeve with higher flexibility and lower caliper.
All BlackBelt products are available with multiple surface options, including the new DG-HD surface (discontinuous grooving with high density groove pattern).