PressBear press roll poly cover provides stable nip in tough press conditions
Metso polyurethane roll covers ensure a stable nip and constant operating parameters in harsh conditions. With approximately 5,000 poly roll deliveries under our belt, Metso is the best provider of proven, reliable and cutting edge poly covers for your hard-working rolls.
PressBear is Metso's polyurethane roll cover specifically developed for press roll positions. Metso has developed the PressBear with one overall goal in mind: survive the toughest conditions.
PressBear is made with a premium material that saves paper mills money. It does this in two ways. First, it will run two to three times longer than rubber covers in the same application, resulting in more time between grinds. Second, in most cases no water cooling is needed, thus lowering actual operating expenses. Benefits of the PressBear poly roll cover include:
- Less stiffness drop
- High operating temperature
- Lower hysteretic build-up
- Increased life between grinds
- Greater wear resistance
PressBear meets the needs of many types of press positions. For direct sheet contact or plain press roll covers it is called PressBear. Suction roll covers are PressBear S. For the grooved vented roll press position the name is PressBear G. When the need is for a blind drilled roll cover, Metso Paper has a computerized program to recommend the correct hole size and pattern. This is based upon the type of paper produced and the operating conditions. For a blind drilled roll cover, the name is PressBear BD. Various combinations can be supplied as needed.
How can the PressBear cover be so versatile?
The cover is available in a hardness range covering many types of application. This property, combined with its excellent dynamic characteristics, will contribute significantly to improved sheet quality and a more consistent operating environment. The 220 ºF maximum temperature range and 1600 PLI maximum allowable loading of the PressBear cover means that additional press positions can utilize the benefits of a polyurethane cover. PressBear is not speed limited and will provide better vibration damping than conventional covers.
PressBear has been running successfully in many types of applications since 2001. It has met the demands of all types of position from soft-nip calender roll covers to press roll positions to pulp machines. Feedback on the running success of the PressBear polyurethane roll cover has proven that it will meet the challenges of future paper making needs.
Nip pressure stability
When you are considering purchasing a polyurethane roll cover, you have one overall goal: nip stability. The PressBear polyurethane cover has specifically been developed to provide a stable nip under actual operating conditions. Excellent wear resistance means that PressBear will keep its crown profile longer than a conventional roll cover. The most technically advanced materials are used in production.
Excellent heat resistance
PressBear not only has a high surface temperature heat resistance but also generates very low internal heat. This allows mills to operate without water cooling, which can provide major cost savings. In many cases only the addition of a water/glycol mixture is needed to keep the temperature even within the roll body.
Uniform hardness stability
An advanced production technique gives the PressBear a hardness that is very uniform across the roll cover face and is maintained during actual operating conditions. Some polyurethane roll covers exhibit great properties on the paper machine floor but change drastically once they reach the actual conditions of the press nip.
The PressBear has a slower water intake and stabilizes after a lower amount of water has been absorbed. This means PressBear will have a negligible change in hardness.
With the development of a new polyurethane cover that takes the performance of roll covers to a higher level came the need to develop a superior bond system. The testing of our PressBear adhesive system has proven that the bond is up to the same high level of performance as our PressBear cover.
With the PressBear polyurethane cover you can set your machine operating conditions and know you will not have to worry about changing them prematurely.
For more information on the suitability of the PressBear poly cover for your press section, or to discuss any other Metso poly covers, contact your Metso representative.
