Ask: the limit of the spindle rigidity tapping, recently doing rigid tapping tests of the nc machine tools

Recently doing rigid tapping tests of the nc machine tool, the purpose is to verify the machine tool spindle in rigid tapping limit and stability.Then meet some big problems, such as: ‘h9 P – m. HT3 k\/N8 i1 P7 P5 integrated t2 q8 G\/s tapping tapping into what is the limit?Now using extrusion tap tapping stainless steel screw, tapping the 3000 hole, tap wear and tear, but did not break, still can continue to use, the threaded hole observation, can really see inside screw tooth clearance change is big, burr became more, such calculating do not calculate tap into life, cannot continue to use?!K5 W5 @ 8 [% _; w ‘U8 V6 d in other words, tapping the thread in what state is not qualified?. N)? – Q + P % O % u2 @ the G5 F9 N + N) threaded hole thread strength how to test, what is the simple and reliable method, or device? \/ e! L6 J) L # L “];?;K7 h2 U (j. I – X limit