Product Details Supplier Info More products

BEP Surface Technologies has supplied its largest ever copper-shelled chill roll to Mondi Orebro in Sweden.

Measuring 900mm diameter by 3,350mm long and weighing five tonnes, the high-efficiency chill roll has the capability to increase running speeds while reducing cooling costs, according to BEP.

The roll will enable Mondi to manufacture products to specifications not possible with previous rolls.

Mondi Orebro is a laminating specialist focussing on the production of extrusion coated materials for the industrial papers market and is part of the Mondi Group, an integrated packaging and business paper producer with 33,400 employees at 118 production sites across 34 countries.

Addressing concerns over quality, delivery and technical support for its laminating lines chill roll fleet, Mondi Orebro contacted Manchester-based BEP Surface Technologies.

Discussions focussed on roll build quality, stiffness and consistency of surface finishes.

The copper-shelled chill roll was delivered and tested in July.

Jonas Zittra, technical manager at Mondi, reported that under normal processing conditions the company was able to run good quality product from the outset.

Subsequent tests on a more demanding specification where they usually experience release problems due to the tackiness of the polymer gave better release performance and less web breaks.

‘Previously we could not set the polymer profile on the base paper, neither could we run overcoat on the edges of the roll,’ he said.

‘As a result, we had high scrap rates because we had to set the film on customer material.

‘Using an elevated chill roll temperature we achieved better release properties, which enabled us to run both overcoat as well as profile setting on a normal base paper rather than customers’ stock.

‘Our next test will be to evaluate speed/adhesion performance with elevated chill roll temperatures – especially when coating glossy MG-papers – and we expect to see an increased speed due to the higher thermal efficiency of the copper shell as well as enhanced release performance,’ he added.

For the copper chill roll BEP produced a thick-walled copper shell using its electroforming technology to produce a fine-grained, seamless copper tube measuring 900mm x 3,350mm.

This copper shell was then shrink fitted onto a high-stiffness steel inner core before final machining, hard chrome plating and surface texturing to Mondi’s specification.

The copper-shelled roll was part of an order, the first from the Mondi Group, for two new rolls, one in copper and the other with a steel shell.

Weighing 4.7 tonnes, the steel roll measures 900mm diameter by 3,250mm long and features a high release matt chrome surface.

BEP also refurbished an existing steel roll with a diameter of 760mm and length of 2,350mm.

This roll had badly damaged journals as well as corroded and blocked waterways.

Machining and electroplating operations were undertaken to restore it to its original condition.

Restoration processes included acid cleaning internal waterways to reinstate cooling performance and electroplating and machining the journals to original tolerances.

The roll body diameter was finish machined, hard chrome plated and surface textured to Mondi’s specification.

BEP Surface Technologies

View full profile