Despite our strategy which is mainly focused on on-site machining, replacing parts is sometimes unavoidable due to wear constraints.
Since 2010, Novexa has been the exclusive distributor for Group Defawes / Bierens in France and other French speaking countries on the following applications:
- Supply of large dimension parts (girth gear, tires, pinions, up to 4,000 mm)
- Refurbishment of damaged reduction gearboxes in the workshop in Ghent
- Calculation and sizing of the gears, reduction gearboxes and rotative tubes
Defawes is a specialist in gears and reduction gearboxes.
Based on a 130-year experience (the company has existed since 1880), we deliver for them gears with unique cutting characteristics under DIN 1 to DIN 4, which are destined to the industrial market or small series for Original Equipment Manufacturers.
We are able to supply parts from foundries or wrought parts for open gear drives, tires and reduction gearboxes. Refurbishing a gear of a reduction gearbox requires an efficient engineering service that is involved during the power calculation, the sizing of the gears and the casing as well as the controls to choose the material and their hardness, etc.
Furthermore, reduction gearboxes, whatever their brand or origin, can be refurbished in our workshops. The controls are completed using 3D machinery which define all data quickly (module, pressure angle, helical angle, specific data in the case of bevel gears or herringbones). We are completely independent in the maintenance of the parts and do not call upon the manufacturer. The result of our assignment is always of top quality, quick in terms of turnaround time and more economical than the manufacturer’s solutions.
The quality check is completed with a 3D measurement system and uses the CNC machines’ precision to verify the measurement. Regarding gears, we compare on a test bench the actual load bearing capacity on the gearing with the calculated load bearing capacity. This technique is essential in order to optimise load bearing capacities and limit the appearance of pittings and scratches.
Our 5-axis free form milling machines produce a variety of gears
TThe gears are usually milled and corrected after machining to produce the desired precision. Defawes & Bierens is the only gear manufacturer which is able to combine machining and up to DIN 1 tolerance, thanks to a 5-axis milling.
In order to remain flexible and competitive, the Technology & Development department of Defawes and Bierens has developed a universal production technology. It is thus possible to develop those tooth shapes or corrections, which cannot be manufactured with standard tools. This cutting edge removes all limits regarding size or shape.
This technique is suitable for any gear for which a mathematical description has been previously developed internally, such as:
- Cylindrical gears with straight, helical or V-shaped teeth
- Conical gears with straight or curved gears
- Worms and wormwheels
- Crownwheels / Crown
- Racks and various kinds of shapes
- 20 year experience in reprofiling
- 5 day intervention time on average
- 85% to 90% % in cost reduction compared to the systematic replacement of parts.
Our teams are at your disposal.
Enquire with our experts