Page 65 - Demo

63INDEXABLE INSERTSSelf-ClampingInsert ConceptIndexable inserts are fixed in the insert pockets mainly by mechanical parts such as screws, levers, clamps etc. Back in the seventies, ISCAR introduced SELF-GRIP, the brand name of the original blockbuster parting tool design concept. According to the design concept of the SELF-GRIPtool (Fig. 9.11), a pressed carbide insert was clamped into a tool blade using the blade%u2019s elastic forces without the need for mechanical securing elements. At that time, other manufacturers also attempted to clamp inserts into a parting tool using the same principle. However, it was ISCAR that invented a reliable, truly workable concept that set the benchmark for parting applications and created the game changer in parting.Fig. 9.11. SELF-GRIP parting tool. The insert is fixed in the pocket without mechanical elementFig. 9.12. Turning tool with tangentially clamped insertClamping TorqueProper insert fixing by a clamping screw, or any other screw-down element requires applying an appropriate tightening torque (clamping moment). Cutting tool manufacturers provide the appropriate torque values in technical data sources. In addition, the values are usually marked on a tool body directly marking details.The design of various keys or wrenches, delivered by the manufacturers as accessories, ensure the necessary torque. Alternatively, there are dynamometric keys with adjustable or fixed torque (Fig. 9.13. ) that provide a good option for applying correct torque. A clamping screw, which is the smallest and weakest element of a tool as a system, has a great impact on the system%u2019s reliability. The over-tightening of screws often results in fatigue failure of the screw or difficulties in releasing the screw after machining, and dynamometric keys are highly recommended for reliable insert clamping.