Bohui BM 3: Information on the Voith scope of supply

Headbox and wire section. Three MasterJet III-F headboxes with lamella technology: the headbox with dilution water technology in the intermediate ply ensures optimum cross profiles. The wire section is a conventional three layer wire section with a DuoFormer D on the intermediate ply. The DuoFormer D is one of the latest generation formers from Voith designed for very high dewatering performance. In addition, a DuoShake is used on the intermediate ply for optimum fiber orientation and improved strength values.

Press section. The press section consists of a Tandem NipcoFlex press, followed by an offset press for optimum surface quality. Both NipcoFlex presses are double-felted and designed for a maximum line load of 800 kN/m. A steam blower box is installed upstream of the second nip for moisture cross profile control.

Sizing press and dryer section. The pre-dryer section is normally two-tier, with the first three dryer groups single-tier with DuoStabilizers. The SpeedSizer AT can run in SpeedSizer mode and as a conventional sizing press, in which case Voith SizeWings enable higher operating speeds for starch feeding. At the end of the after-dryer section there is an EcoCal Hardnip calender including upstream nozzle-type moisturizers to obtain optimum smoothness in the base paper. To also achieve optimum smoothness at high speeds, very high temperatures are necessary on the heated roll, so it is fitted with an external FlexiTherm coil.

Coating section and finishing. The coater comprises four DynaCoat AT coating units, each with a JetFlow free-jet applicator, which applies the coating color in a contactless fashion less likely to cause damage. The first two coating units apply the preliminary coat, the third applies the rear coat and the fourth the top coat. The coating is dried by means of InfraAir drying, InfraRed dryers, MCB high-performance dryer hoods and an HCB Turn air drying and contactless web turning system.

A curl correcting section with six drying cylinders corrects the paper curl. The final surface treatment is done by the EcoSoft calender. To reel up the high-quality board without damaging it a Sirius roller with EcoChange reel change system was installed (maximum winding diameter 4.4 m). Two VariFlex winders perform the next process stage.

The automation technology comprises

• the process control system for stock preparation, the wet end process and the steam, condensate, hood and air systems of the board machine.
• the machine-level control for the complete board machine
• the entire quality control system with six scanners and
• the complete machine monitoring system for monitoring the roll bearings.

Clothing. Complete first clothing for the board machine.