Mapal Fine boring tools for valve housings optimise productivity
Germany – In automatic transmissions, the switching unit is the central component that controls the clutch and the brake for changing gears and the speed of the vehicle.
Similarly, in manufacturing, the valve bores play a central role in the switchgear housing. And to increase productivity during machining, Mapal has developed multi-bladed PCD tools with permanently brazed cutting edges.
The housings consist mainly of a die cast-aluminium alloy, which Mapal says is dependant on its manufacturing quality. The tolerances of the cylinder form of below 8 μm, roundness below 4 μm and surface finish with radii below 3 μm have to be reliably achieved during production, which are offered mostly by stepped valve bores.
Their machining is divided into several machining sequences, with different tools for piloting, semi-finishing and finishing, Mapal explains.
As maximum precision is not needed for every valve bore, the company offers permanently brazed PCD fine boring tools that reduce process time and a minimally extended tolerance range.
Moreover, these tools are said to eliminate the need for fine adjustment of the cutting edges.
For intermediate machining, four-edged PCD tools with brazed cutting edges shorten processing times and positional accuracy is also achieved, Mapal says. Furthermore, three to six-edged fixed PCD fine boring tools are available for finishing work which can improve cycle times with almost the same precision.