Valve blocks/control housing can be machined very precisely and effectively with fixed diameter honing tools. Fixed diameter tools are suitable for the requirements of honing operation of passage bores of valve blocks/control housings due to their construction (no burrs, sharp-edged).
Test setup for processing through bores in a valve manifold with control edges:
Bore length: 240 mm
Diameter: 25 mm
Allowance: 30 µm
3 honing operations, resulting cylindricity lt. 2µm, roughness approx. Rz=1µm