Beta-Roll® for Calenders
Beta-Roll® for Calenders
The Patented Beta-Roll® for calenders consists of a simple mechanical system, unlike complicated systems produced by other manufacturers, and requires very low maintenance, thus drastically reducing machine’s operating costs.
The Patented Beta-Roll® consists of an assembly of three main items: the axle, the internal tube and the external tube. The axle is supported by two oscillating bearings at its ends, where the squeezing load from the pneumatic actuators is applied.
The internal tube is supported by other two oscillating bearings placed on the axle and has four sliding races on which the external tube is supported. The bending is therefore reacted mostly by the axle and in part by the internal tube: the residual deflection of the external tube (which works on the fabric) is absolutely negligible and the final pressure distribution is even and constant along the whole roll span thus leading to the best results in the uniformity of treatment.
The Patented Beta-Roll® for calenders allows to reduce the deflection to negligible figures with respect to the traditional construction and this is an essential requirement for calenders in order to achieve a perfectly uniform treatment on all the fabric width.
Some manufacturers adopt crown rolls (larger diameter at the centreline and smaller diameter towards tips) in order to partially compensate for the bending. In this way, the calender works correctly only at the design pressure where the deflections are compensated: but at different pressure values the deflection is not compensated anymore and the problem remains unchanged because the pressure distribution is not even.
Instead, the Patented Beta-Rolls® for calenders are all parallel ground (same diameter for any section) and this is obviously a great contribute to achieve a perfectly even load distribution at any working pressure value (from zero to the maximum). The use of BETA calenders is therefore much more flexible compared to calenders with traditional and crown rolls because it allows to face each treatment and each working pressure while maintaining the best precision and uniformity of pressure distribution with the best final results on fabrics. Beta-Rolls® for calenders can work from zero to max load (up to 300N/mm) always maintaining a negligible deflection on the centreline.
When heat treatment is required by production needs, BETA calender can be equipped with one or more rolls suited to this use. The steel Patented Beta-Rolls® for calenders can be heated by passage of diathermic oil (250°C max): oil flows from an end to the other end of the roll inside an interspace between the internal and the external tube. The new BETA Patent for calender’s rolls also covers technical aspects in order to assure a perfectly even temperature distribution: the steel heated rolls have an internal layout (in terms of design of oil path and minimal flow resistances) such as to uniformly spread the heat along the whole roll span and roll surface. Temperature deviation between the two roll’s ends results to be no more than ±1°C.
Steel rolls diameter
Nylon rolls diameter
Max working pressure
1800 mm/3600 mm
2600 mm/4000 mm*
* On request working widths over 4000 mm are available