Sunnen’s SVL-2115 bore finisher is a multi-stage automated lapping machine that laps and air-gauges bores in a single set up.

The machine is aimed at aerospace part manufacturers seeking a cost-saving solution for bores with large length-to-diameter ratios and tight tolerance requirements. Such parts include hydraulic valves, sleeves, fuel system components and other parts that are prone to distortion when honed.
Bringing increased productivity and part consistency to what is traditionally a manual process, the SVL-2115 is based on Sunnen’s existing SV-2115 honing system. The patented system control is designed for unattended operation and automatically laps and air-gauges bores throughout the cycle. Gauge readings are fed back to the control and the cycle is repeated until the parts are within specification.
Says Phil Hanna, Sunnen’s product manager: “For very expensive parts, an automatic lapping process reduces the possibility of scrap components due to human error. Since lapping is usually the last process during the machining of a workpiece, if the lapping is not correct, all the work to get the part produced up to that point is wasted.”
Patented Sunnen lapping tools are available for workpiece diameters from 6.3 to 45 mm, and lengths up to 12 times the bore diameter (not to exceed 200 mm). Additional diameter ranges are in development. The spindle speed range is 100-2000 rpm during lapping, but the machine is capable of slow speeds for non-powered steps, such as lapping paste application or slow-rotation bore entry. Stroking speed is 0-350 SPM, with stroke length optimised to achieve a high degree of cylindricity.
For further information www.sunnen.com