Panel Ripping - Flexible and Efficient
HOB - Die Holzbearbeitung, 1-2/2003
By Dipl.-Ing. Roland Ströhle
(Dipl.-Ing. Roland Ströhle is the head of the technical multirip saws department at Paul, Dürmentingen)
The 78-year-old South German company PAUL Maschinenfabrik GmbH & Co. of Dürmentingen counts among the leading manufacturers of throughfeed multirip circular saws for the industrial ripping of all kinds of panels of all common formats.
The proven PAUL K3 and K34 multirip saws of which thousands are in operation worldwide are equally suitable for ripping solid wood (e.g. for the production of parquetry) or panel materials (e.g. in the particle board, laminated flooring, furniture, door and chemical industries). The K3 / K34 series have become generally known as the PAUL Saw. They are distinguished by their roller feed system which ensures highest productivity. The removable saw shaft with fixed tooling offers convenient tool change.
Continuously increasing quality requirements and the demand for high flexibility with decreasing batch sizes combined with minimal set-up times led PAUL before LIGNA+ 2001 to upgrade the K34 model to a machine with independently positioned saw heads. The prototype of the K34 GS was sold to a leading German laminate flooring manufacturer some months before the exhibition. This machine went into production in January, 2002 and in the meantime it has become a reliable and highly efficient rip saw processing up to ten double size panels per minute in three-shift operation.
The main objective of further development was to reduce the investment cost whilst increasing flexibility, maintaining the proven consistent reliability, high cutting quality and recognised ease of use. With the K34 VARIO it has been possible to combine all these features. This second generation machine will be presented at this year's LIGNA+ before being delivered to the German production site of one of the world's largest laminate flooring manufacturers. The machine dimensions are essentially identical to that of the K34 G so that it can easily replace a K34 G in an existing production line.
The tremendous flexibility of the K34 VARIO is achieved by independently CNC-controlled tool heads. Thanks to the intelligent configuration of the tool heads and the facility to move them into a parking position outside the cutting area, the K34 VARIO is suitable for ripping panels into any number of strips without the need for any manual change-over measures. The minimum strip width is 185 mm or even 95 mm, depending on the configuration concerned.
Various machine features ensure high quality processing. Sawing or hogging from the bottom against the feed produces a chip free saw cut on the top (good) side of the workpiece. The arrangement of top rollers directly before and after the cutting area and the large supporting tables contribute to achieve maximum cutting quality. Accurate strip widths are obtained thanks to the exact positioning and pneumatic clamping device on each tool head. Polyurethane-coated top rollers ensure careful workpiece handling. A multitude of powered feed rollers guarantee correct timber guidance.
The reliable CNC control (LINUX operating system) designed for industrial application is a user-friendly, clearly arranged in-house development. A calibration function provides for the automatic adjustment of machine and tooling tolerances. Other features such as the so-called "laminate calculator" which enables the control to take account of the paper growth in a very simple manner are available as an option.
Great importance has been attached to easy accessibility for tool change or maintenance work by simply moving all tool heads to a parking position on the operating side. Thanks to the use of a quick clamping system the tool change is further facilitated. Dust extraction hoods with optimized airflow properties completely surrounding the tools provide for concentrated sawdust collection. This protects the system against contamination and minimizes wear, in particular, when ripping abrasive materials (laminate).
For many years PAUL have also supplied automatic panel alignment systems for the laminate flooring production. Printed markings (reference lines) are recognized by CCD cameras or color recognition sensors and the workpieces are automatically aligned and ripped with a maximum speed of 10 panels per minute. The combination of rip saw and alignment facility offers the benefits of a compact system with optimum alignment quality and maximum productivity. The alignment station is suitable for use with a classic K34 or the new K34 VARIO.
PAUL are also able to deliver highly efficient, reliable and sophisticated panel rip and cross-cut systems (including comprehensive handling equipment) operating on a throughfeed basis.