The Fagus shoe last factory is an architectural treasure and the founding building of the famous Bauhaus architectural concept.
Built in 1911 in Alfeld, not far from Hanover in orthern Germany, to house the then-booming wooden last business of Carl Benscheidt, it still looks modern.
But how did the GreCon of today come from a shoe last business? (For those who don’t know a shoe last is the re-usable ‘mould’ around which a shoe is made).
Fagus did not only make lasts, but also made the machinery used in their production and this led to the manufacture of woodworking machines and ultimately to Grecon Dimter, a joint venture with machinery maker Weinig, which has a factory in the south of Germany.
There was another connection to the panel industry: in 1958, Ernst Greten senior, father of fourth generation Berndt, Ernst and Gerd, developed a wind-sifting system for particleboard, which in turn led to the establishment of the company Bison, which supplied machinery for complete particleboard and MDF lines until the mid-1990s.
In 1974, the brothers Ernst and Gerd founded the electronics side of the business, GreCon, so well-known in the panel industryworldwide today.
The fifth generation of Gretens is represented by Kai, son of Berndt, and he is technical director of the electronic department in Alfeld, responsible for R&D and manufacturing.
The GreCon range includes on-the-line and laboratory quality control systems, safetysystems and measurement systems.
Among the most recent innovations –both in the last 12 months – are the Superscan and the Dieffensor.
Superscan is a camera-based inspection system for panel surfaces which operates at the full line production speed. It is designed to detect defects in raw board surfaces or laminated, lacquered or printed finishes and GreCon has just supplied its first two-sided system for top and bottom decorative faces.
Dieffensor, developed jointly with Dieffenbacher, detects foreign bodies or resin lumps in the fibre or particle mat, and also double-checks the forming accuracy.
Calibrating any online measuring system is obviously vital and, until recently, this could only be done during plant shutdowns.
However, now GreCon offers its bond detection and thickness sensors mounted on a ‘C’ rather than an ‘O’ frame so that one half can be pulled sideways out of the line for calibration and cleaning without interruption to production, or losing all the information which the sensors provide. This is known as the ‘ct-Concept’.
For moisture measurement on the line, the company offers an infra-red system, IR 3000 and a microwave system, MWF 3000.
The MWF 3000 can also be expanded to a density analyser to obtain moisture content and density data simultaneously.
The IR 3000 has a non-contact measuring head and operates on the principle that higher moisture content material absorbs more of the infra-red light.
The online measurement of weight-perunit- area is carried out by the BWQ 3000 traversing gauge, which is again non-contact, employing x-ray technology.
The Stenograph is an online density distribution analyser, also employing x-rays.
Online blow detection is an important quality control tool with the potential to save material wastage and line stoppages and GreCon’s UPU 2000 employs up to 16 inspection channels mounted on a frame across the width of the production line.
For online bond quality measurement,the company offers the UPU 3000 with up to 22 inspection channels.
There are two online thickness gauges: the DMR 2000 with measuring rollers and the DMR 3000 with rhomboidal technology.
“Most panel manufacturers produce above their own quality standard to be on the safe side,” said Kai Greten. “We can help to reduce raw material consumption but maintain standards by the best use of measurement systems and this can give a big competitive advantage.”
An infra-red cyclone plug-up detection, and spark detection and extinguishing, systems make up GreCon’s safety-related products.
A new development here is the OPC interface to Siemens, Allen Bradley or other standard control systems and from there to visualisation on a central control room display, rather than on a separate console on the individual equipment cabinet.
“This will help to identify exactly where a problem occurred to prevent it happening again,” explained Mr Greten. For the laboratory, Labrob and Bondcheck are offered, together with the DA-X density analyser.
All GreCon measuring systems come with on-line help if required, giving the operator access 24/7 to its technical staff. “All systems we supply are available here on site in full-function, full-scale so if the customer wants to test a new product, we can do it here. We can also investigate any problems and give troubleshooting advice,” said the technical director.
The company also makes all its products inhouse, only buying in printed circuit boards and equipment cabinets. It employs 21 people just in R&D, out of a total of 350, and has 40 service engineers travelling to customers, 22 of whom are Alfeld-based.
GreCon also has a subsidiary in Tigard, Oregon in the US where spark detection and measurement systems are assembled from Alfeld-produced components, and subsidiaries in the UK and Strasbourg. It also opened an office in Shanghai last year, as well as having agents in Australia, Asia and Europe. “Our main objectives for our customers are to minimise raw material and energy consumption and improve quality, while at the same time providing maximum protection to prevent fires and explosions in filters, pneumatic and mechanical conveying systems,” concluded Mr Greten.