Dedication to innovation and quality has empowered the French group ABK to supply to one of the biggest fluting & liner manufacturers worldwide, for one of its paper mills in Indonesia, a new and high- tech press section made of suction bi-nip and shoe press which characteristics can guarantee a dryness level over 50% in all working conditions, and allow for very short times in terms of press and felt changes as well as press maintenance. This equipment is designed for white top test liner width 4510mm at pope reel, 125 to 200gsm, produced at a structural design speed of 900m/mn. Erected, commissioned and started successfully, this press section and especially the shoe press have enabled immediate saleable paper production with results ahead of expectations.
Major benefits compared to a conventional roll press
There are several considerable benefits that support a press section realised with a made-in-ABK shoe press. Technically and more generally speaking, the shoe press is now state-of-the-art product for the board-making sector and the packaging paper machines because of the advantages it brings in terms of improved paper quality and enormous increases in productivity; flat pressure gradients which ensure: high dry content; increased and improved strength values; uniform web compaction and a constant CD moisture profile; and also minimized open draw which reduces the paper breaks due to the structure design.
Characteristics of the shoe press
The PLC (Press Long Contact) is operated with a belt which turns around a shoe. The belt functions like a roller jacket, but it is elastic and flexible. Shoe press belts are either smooth or grooved. The dewatering capacity depends upon the type of belt and felt.The nip force is provided through a 6” piston that reaches completely across the machine. A lubrication shower placed ahead of the shoe forming a thin film of oil between the shoe and the belt. This allows the blanket to turn and prevents the shoe from acting like a brake. At the exit side of the nip, the oil is doctored off into the save all pan by the air loaded wipe.
Characteristics of the CC roll
The CC roll is a roll with variable crown and internal piston. The one installed on Indonesian site is of the hydrostatic type bearing in mind the efforts implemented (1000 kN/ml). But ABK is able to manufacture also a shoe press with a CC roll of the hydrodynamic type which can have some advantages especially in terms of maintenance. But whatever the type of CC roll manufactured, ABK always supplies simple system easy to maintain, and does not manufacture too complex products (especially in regards to pumps) so to avoid potential wad damage over ribs, and maintenance constraints.
Load system (CC roll / PLC)
The load system can also makes the difference:, ABK has one or two continuous rectangular pistons, similar to the CCR piston. It has a very good CD profile. MD profiling is an option. Other suppliers propose shoe presses with two cylindrical in-line rows of pistons which make the control of the MD and CD profiling more complex.
Benefits from cantilever Frame
ABK has decided to manufacture its shoe press with a cantilever frame coupled with the use of strungs instead of mounting beam so that disassembly of any press can be done easily and rapidly independently from all other presses. This specific structure also permits a very efficient felt changing process.
Mounting and changing performances
The technology developed by ABK in the engineering and production of the shoe press allows for incredible mounting and changing performances for all elements of the shoe press: for transfer roll 3h00; for Pick Up Press 2h00; for 1st Press 4h00; for Central press 4h00; for CCR 5h00; for PLC module 2h00; for Blanket 0h45; for Pick-up felt 1,5 hours; for 2nd NIP felt 1,5 hours; and for Shoe Press felt 1 hour.
Tail threading device
The technology developed by ABK in regards to the press structure leads to no open draw; the sheet is always sustained by felt, and all rolls are driven and synchronized so that there is no sheet break.
Blanket clamping
ABK has improved the inflatable ring for a much cheaper and efficient clamping, by means of an inclined ring which is very simple to install and with a changing time around 1.5 hours. This is another advantage of the ABK shoe press compared to competitors where the shoe press has a slow system which requires the tightening and loosening of the front and backside bolts.
Cost saving and paper quality
In shoe press systems, a long-nip residence time will positively affect dewatering dynamics, while using less costly raw materials. This saves energy and cost in paper manufacture. Besides, it improves paper quality and strength. Moreover in terms of investment, it is worth the main strong point of ABK is that the customer can integrate in its paper lines proven technology at an affordable price.
