Machining Process Description :
The casting are shot blasted and are sent to the machine shop for machining operation, the first operation is the roughing operation where casting skin is removed, this operations is performed on a custom designed vertical high speed turning cum boring machine. The machined liner is then turned on a CNC Turning Center where all outer diameter and lengths are maintained, for Dry liners the next sequence of operations would be Rough Grinding, fine boring, Rough honing followed by Plateau honing and Finish grinding where as for Wet Liners after CNC turning, fine boring followed by rough honing, fine CNC turning and plateau honing would be performed.
Honing has been and will remain to be in the foreseeable future the only process available that could provide both the required surface roughness and the cross-hatching in cylinder liners. The cross-hatching lay direction is needed to provide means for retaining lubricants.
A cylinder liner has fairly intricate surface requirements due to its complicated functions. It has to provide adequate surface roughness to resist wear and to store and retain lubricants during high temperatures, in addition to liner hardness, geometric dimensioning and tolerancing to ensure other proper functions.