In passenger-car engine production, crankcases made of cast aluminium alloy with coated cylinder bores are the current trend, the objective being to produce engines that are more compact and ultimately more environmentally friendly.
Using the new boring tool from Walter that has a high-precision PCD cutting insert, customers can prepare the surface for the coating mechanically. Extremely fine cutting edges with a width of less than 0.2 mm line the cylinder bore with a filigree profile with undercuts that is accurate to the nearest micron, into which the coating metal penetrates and is positively keyed.
Because it is equipped with only one cutting insert, setting the tool is simple, making process reliability during use extremely high. Walter provides suitable inserts for all commonly used coating processes. Immediately after boring the engine blocks, the cylinder bores can be machined in the same clamping arrangement. This feature is the big advantage in comparison to classic roughing techniques using water or corundum blasting, which require special equipment.