1. Viktor P. Astakhov
Common Problems and Solutions in Cutting Tools Implementation Practice in the Setting of Automotive Powertrain Plant: System Outlook

2. Introduction What is a Tool Commodity Management (TCM) Company?
The basic objectives of a TCM company set by the automotive industry are:
To keep production lines running while meeting quality requirements.
To meet a cost per unit (CPU) target set by the customer.
To assure direct tooling cost savings per year as required.
Viktor P. Astakhov IMTS 2008

3. Introduction Virtuality vs. Reality
In the ideal world, these three objectives are the parts or facets of the tool management continuous process, which can be run by business management-type personnel with some engineering training.
Any practical tool management process is a discrete process consisting of a great number of “Problem Occurrence-Problem Solving” dyads (couples). A problem occurrence can be thought of as failure, referred as tool failure. The tool management process runs smoothly if and only if each and every dyad “Problem Occurrence-Problem Solving” is completed, i.e. when for each problem that occurs on the daily basis, a proper, timely solution is provided. To accomplish that, a fast-respond problem solution system established by of any modern TCM company.
Viktor P. Astakhov IMTS 2008

4. Introduction Example of the machining system (drilling)
Viktor P. Astakhov IMTS 2008

5. Introduction Right Tool at Right Time at Rite Price
“Right time” is when the customer needs the tool to keep its production running.
“Right cost” calculates through CPU for a given application.
The term “Right tool” is totally illusive.
The “right tool” can be thought of as that one made to the print approved by the customer (an automotive company) and thus posted in the corresponding tooling database system. However, if this tool does not work properly, the blame goes to a TCM company, which has little to do with its design and approval. Moreover, a TCM company is responsible for the investigation of the tool failure.
Viktor P. Astakhov IMTS 2008

6. Introduction Tool Problem Simple questions
System coherence who is responsible?
What resources has a TCM company to investigate a tool failure?
What recourses has a tool manufacturer to investigate a tool failure?
Have you ever seen a 5Why analysis that point the root cause for the tool failure problem?
As seen
As it is
Viktor P. Astakhov IMTS 2008

7. Some Common Problems and Solutions
Viktor P. Astakhov IMTS 2008

8. Cutting Through the Veins
Viktor P. Astakhov IMTS 2008

9. Veins Cutting Through the Veins Common drill and its geometry
A reason for high point angle
Viktor P. Astakhov IMTS 2008

10. Cutting Through the Veins
Sladge
Veins
Viktor P. Astakhov IMTS 2008

11. Veins Cutting Through the Veins Improved drill geometry
Viktor P. Astakhov IMTS 2008

12. HSS Tools
HSS
Following tested possibilities to decrease CPU with HSS tools are most feasible:
Application of the advanced application-specific tool coatings
Optimization of the finish grinding and re-grinding practices
Use Diffusion process
Optimization of the tool geometry
Use the advanced tool materials as REX 121 and ASP developed for dry applications
Optimization of the metallurgical properties of the workpiece prior gear machining to achieve its maximum machinability.
Viktor P. Astakhov IMTS 2008

13. Sharpening flaws
HSS
Grinding Burr
Burns
Viktor P. Astakhov IMTS 2008

14. HSS Diffusion© Process
This process has been developed to improve the basic physical characteristics of metals, alloys and composite materials (including cutting tool materials as high speed steels, sintered carbides, PCBN, PCD etc.). The essence of the Diffusion© process is the healing microdefects and strengthening of interfacial bounds that enhances the physical and mechanical properties of materials. This healing is achieved by introducing a high density energy flux (the rate of transfer of energy through a unit area (J·m2/s)) through the entire cross-section of the material in a strictly controlled fashion. The diffusion© process results in the increased tensile strength by 5 – 25%; wear resistance - by 30 – 300%; fatigue life by 50 – 400% and decreased friction by 30 – 60%. This process does not affect the final dimensions and shape of the parts, as well as it does not create any superficial and in-depth residual stresses. As a result, this process is normally applied as a final operation after any kind of heat treatment or coating, grinding and polishing.
HSS
Viktor P. Astakhov IMTS 2008

15. Diffusion© Process
Results
HSS

16. Carbide Tool Carbide Tool
In the author’s opinion, the following tested possibilities to decrease CPU with carbide tools are most feasible:
Application of the advanced application-specific tool coatings combined with high polish of substrates and airlapping after the coating.
Utilization of the application-specific carbide grades developed for machining aluminum.
Optimization of the tool design and geometry.
Synchronization and optimization of drill-rougher-finisher operations including the use of combined tools.
Viktor P. Astakhov IMTS 2008

17. Carbide Tool Common flaws Improper carbide grade + incorrect geometry
Coarse grind
Improper carbide grade
Viktor P. Astakhov IMTS 2008

18. Carbide Tool Example of Case Studies
Upper Valve Body, aluminum alloy 380
Carbide straight flute combined drill –new coating for Al applications
A regular tool design with a new coating has been tested using the same machining regime, tool material and other machining conditions (2 tools were tested). The analysis of the test results shows:
Tool life tripled
Average tool life – 2,500 cycles
Tool life of the tested tool – 7,500 cycles
Tool wear type is normal for the work material
Both margins do not show any excessive wear as with the regular tool. No wear marks were found on the additional supporting areas made on the heels. This shows that the tool maintained its working integrity during the whole tool life
All the cutting edges (drill, reamer and chamfer) have uniform wear.
Carbide Tool
Viktor P. Astakhov IMTS 2008

19. PCD PSD Tool Some most common flaws found in PCD tools Brazing
Viktor P. Astakhov IMTS 2008

20. PCD Some most common flaws found in PCD tools
Gap between PCD inserts and the tool body
Viktor P. Astakhov IMTS 2008

21. PCD Some most common flaws found in PCD tools
Viktor P. Astakhov IMTS 2008

22. Recommendations
The following is recommended to both tool manufacturers and users to avoid the discussed and many other common and specific problems with PCD tools:
Use application-specific PCD grades
Specify, inspect and maintain surface roughness on the ground surfaces of PCD inserts
Specify brazing quality
Specify and inspect the backtaper
Use proper re-sharpening/re-tipping strategy
Use proper machining regimes for PCD tools
Pay particular attention to carbide grade selection for PCD-tipped drills
Design and manufacture tools with no gaps between PCD inserts and carbide bodies, with overhanging of PSD inserts, with coolant holes directed into the machining zone (not before and not after), with 5-10 microns radius of the cutting edge (edge preparation) etc. Note that the diameter of the coolant holes as well as the location of their outlets with respect to the PCD inserts should be specified on the tool drawings.
PCD
Viktor P. Astakhov IMTS 2008

23. Importance of the backtaper
PCD
Viktor P. Astakhov IMTS 2008

24. Proper wear pattern c of PCD insert
Viktor P. Astakhov IMTS 2008

25. Standard Tool Standard Tool Standards for indexable inserts:
ISO1832: 2004
ANSI B212-4
Standard for tool holder
ISO 5608:1995
Viktor P. Astakhov IMTS 2008

26. Standard Tool Tools with indexable inserts Sandvik
Valenite in its catalog in the dimensions of tool holder lists without any explanations two parameters “axial” and “radial” having the angular dimension. Seco Tools in the list of its toolholder parameters provides two angles, namely go and gp. no explanations and/or figure are given to explain the meaning of these two angles. According to Bohler turning catalog, practically all of its toolholders are suitable for neutral inserts (N). However, it is not mentioned how the flank angle (relief) is provided by these tool holders. The same can be said about Ingersoll turning tool catalog.
Kennametal (both)
Viktor P. Astakhov IMTS 2008

27. Standard Tool Proper tool geometry ISCAR
External
Internal
ISCAR
Cutting edge inclination angle
Normal flank angle
Viktor P. Astakhov IMTS 2008

28. Standard Tool Consequences of insufficient flank angle
Viktor P. Astakhov IMTS 2008

29. Cracking due to high MRS
Standard Tool
Boring of the liners
Viktor P. Astakhov IMTS 2008

30. Incomplete Tool Drawings
Viktor P. Astakhov IMTS 2008

31. Drawings
Viktor P. Astakhov IMTS 2008

32. Drawings
Viktor P. Astakhov IMTS 2008

33. Tool Drawings Common features
No tool geometry is shown according to the ISO and/or ANSI standard for tool geometry. No edge preparation conditions vitally important fop PCD tools are mentioned (microgeometry parameters).
Although all the shown tools are assemblages, no any bill of material is provided. In other words, no indication of the tool, tool shank and brazing filler materials are mentioned.
No shape and location tolerances are indicated including the runout of the working part with respect to HSK holder as probably the most important shape tolerance.
No surface finish is mentioned.
No particular sizes of PCD inserts including its thickness as well as the thickness of the carbide substrate are shown.
There is no indication how the cutting inserts are secured in the body. Technically, a paper glue can be used and this would not violate the drawing requirements.
Tool Drawings
Viktor P. Astakhov IMTS 2008

34. Importance in-house testing and R&D facilities
If tool brakes or does not perform adequately first time you try it then you may lose the trust of the customer in your ability to solve their tooling problems. As the old saying goes, “You Never Get a Second Chance to Make a First Impression.”
Nowadays, many automotive powertrain plants use modern sophisticated equipment with expensive high-speed spindles. A wreck such a spindle due to tool failure cost a lot.
As a new tool is to produce real parts for real transmissions and engines, the quality procedures require to have a filled out and approved a process change request (PPCR) form before the cutting tool can ever been ordered.
Real production lines and manufacturing cells are not playgrounds because the production time is expensive and limited.
Viktor P. Astakhov IMTS 2008

35. Thank You
"In theory, there is no difference between theory and practice. But, in practice, there is." - Jan L.A. van de Snepscheut
Viktor P. Astakhov IMTS 2008