Technology news: May 2012
Gearbox surface treatment is `1,000 times tougher than paint`
The German gearbox manufacturer Nord Drivesystems has started to apply a surface treatment system to its aluminium gear casings that, it claims, provides the corrosive-resistant properties of stainless steel, without the cost. It says that the NSD tupH system offers a cost-effective and weight-saving alternative to stainless-steel for harsh environments and hygienic applications.
The robust finish uses a catalytic process to bond a base layer permanently onto the aluminium substrate, providing a foundation for a surface sealant. The surface hardness is increased by up to seven times and is claimed to be up to 1,000 times harder than paint, which does not form a permanent bond to the substrate, and can peel off easily.
When applied to aluminium gear casings with stainless-steel components, and combined with suitable sealing and lubrication systems, the new surface treatment withstands washdown and chemical cleaning treatments.
Tests have shown that the treated surfaces are undamaged, even after a year of saltwater rinsing, and the use of aggressive cleaning chemicals and high-pressure cleaners. Salt spray tests showed no corrosion after 1,000 hours.
The treated surfaces are also said to perform well in chip resistance tests. Conventional gearbox coatings and varnishes are susceptible to peeling off and scratching due to general wear and tear, but the NSD tupH coated surfaces are scratch-proof, impact-resistant and do not corrode.
The new treatment is available for most of Nord’s aluminium gearboxes, unlike stainless steel, which is usually available only for a restricted range of products. And because aluminium is much lighter than steel, the treated boxes are particularly attractive for mobile machinery and other weight-sensitive applications.