Recommended values for threading with Walter NTS Feed types and their influence on machining Radial feed Feed via flank 27-29 Changing feed Recom

Recommended values for threading with Walter NTS Feed types and their influence on machining Radial feed Feed via flank 27-29 Changing feed Recommended with Short-chipping materials Hard materials Formation of V-shaped chips Both cutting edges engaged Increased cutting temperature Recommended with Leads bigger than 1.5 mm or 16 TPI In the manufacture of trapezoidal threads Good chip formation Formation of helical swarf One cutting edge operating Chip removal away from the thread Thread flanks with excellent surface finish Recommended with Large leads Long-chipping materials Good chip formation Formation of flat chips Both cutting edges are evenly engaged, thus providing balanced wear Recommended values for the number of radial feeds for each thread cutting pass on manual lathes The recommended cut distributions must only be seen as recommended values. They were determined under good usage conditions with medium-strength steel materials. In the case of high-strength steels, the number of feeds should be increased. It is important to reduce the initial threading cuts in this case. If the working conditions are different, the feed should be modified accordingly. This applies to internal threading cuts with a projection length of more than 2.5 x the boring bar diameter. External operation, UN 60° Lead (TPI) No. of infeeds 32 28 24 20 18 16 14 13 12 11 10 9 8 7 6 5 16 15 0.105 0.126 14 0.004 0.004 13 0.079 0.090 0.004 0.005 12 0.070 0.003 0.003 0.005 0.006 11 0.064 0.003 0.004 0.004 0.005 0.007 10 0.058 0.003 0.004 0.005 0.005 0.006 0.007 9 0.046 0.050 0.054 0.003 0.004 0.005 0.005 0.006 0.006 0.007 8 0.041 0.003 0.003 0.003 0.004 0.005 0.005 0.005 0.006 0.006 0.007 7 0.033 0.037 0.003 0.004 0.004 0.005 0.005 0.005 0.005 0.006 0.006 0.007 0.008 6 0.024 0.028 0.003 0.003 0.004 0.004 0.005 0.005 0.005 0.006 0.006 0.006 0.007 0.007 0.009 5 0.020 0.003 0.003 0.004 0.005 0.005 0.005 0.005 0.006 0.006 0.006 0.006 0.007 0.007 0.008 0.009 4 0.003 0.004 0.005 0.005 0.005 0.005 0.006 0.006 0.006 0.007 0.007 0.007 0.007 0.009 0.009 0.011 3 0.005 0.005 0.006 0.006 0.006 0.006 0.007 0.007 0.008 0.008 0.008 0.008 0.009 0.010 0.011 0.013 2 0.006 0.006 0.007 0.007 0.008 0.008 0.009 0.009 0.010 0.010 0.010 0.010 0.011 0.013 0.013 0.016 1 0.007 0.007 0.007 0.008 0.009 0.009 0.009 0.010 0.011 0.011 0.011 0.011 0.012 0.014 0.014 0.017 Radial infeed (in) Cutting speed reduction A 487 Technical information Threading WALTER Valenite Usage information