Walter has introduced the FW4 and MW4 positive wiper geometries, indexable insert geometries for longitudinal turning and facing that combine the “wiper effect” and the new wear-resistant Walter Tiger·tec Gold grades.
The curved wiper cutting edge makes wiper action universal across various material groups such as steels, stainless steels, cast irons or super alloys. The wiper action can be used to reduce machining time by using double the feed rate, while imparting the same surface finish. In some cases, feed rate increases of up to 300 per cent were successfully utilized. A higher feed reduces the amount of time an insert stays in cut, reducing the friction and temperatures seen by the insert, extending tool life and reducing indexing times. Alternatively, an end user can double the surface quality while maintaining the same feed, which is the traditional use of wiper inserts.
The FW4 universal wiper geometry with a narrow chip breaker, which generates short chips, is for finishing operations. The machining parameters for the FW4 geometry are a feed of 0.0012-0.020 in. and a cutting depth of 0.004-0.100 in. The primary application is turning steel, stainless steel and cast iron (ISO P, M and K workpiece groups), and the secondary application is turning super alloys (ISO S workpiece group).
The MW4 universal wiper geometry with an open chip breaker groove and longer radius wiper cutting edge for high feeds is for medium machining. The machining parameters for the MW4 geometry are a feed of 0.005-0.022 in. and a cutting depth of 0.020-0.180 in. The primary application is turning steel and cast iron (ISO P and K workpiece groups), and the secondary application is turning stainless steel and super alloys (ISO M and S workpiece groups).
Because of the wiper edge with its curved design, improved surface quality, productivity and process reliability is achieved even when the machine tool is not aligned 100 per cent precisely, for example if the turret is slightly offset. The new chip breakers also increase the chip breaking range, reducing the machine downtime caused by the creation of bird nests.