HORN Technology Days 2015 Technical Presentation: Tangential Milling Quality & Effectiveness Speaker: Jeff Shope 2
Outline Quality & Effectiveness A Comparison of Tangential and Radial Systems System Description Material Removal Rate Special Solutions 3
Tangential milling Quality & effectiveness Quality: "The degree to which the characteristics of a product fulfil the requirements placed on that product." Effectiveness: "A prerequisite or obligation on the characteristics of a unit, such as functionality." Source: EN ISO 9000:2005 " refers to how effectively a defined goal is actually achieved. Only the extent to which and the quality with which the defined goal is achieved represent criteria for the presence of effectiveness." Source: Translation of German Wikipedia page 4
Tangential milling A comparison of systems Brief description tangential: Brief description radial: Cutting edges are arranged on the circumference High number of effective cutting edges Favorable application force and clamping force conditions Cutting edges are highly stable Good cutting force distribution Cutting edges are arranged on the diameter 1 insert type, many possible applications High number of cutting edges DIN ISO indexable inserts can be used Good machining at L/D ratios of > 4 5
Tangential milling System description 1 indexable insert for 6 milling cutter types 6
Tangential milling System description Plus left indexable insert for side milling cutters Right version Left version + 7
Tangential milling Material removal rate What the market says: "I need a high cutting speed." a thick chip." a cycle time that's right for me." a certain tool life/tool life in pieces to be achieved." unit costs/costs per part that are right for me." "I'll wear them all out!" "That's far too slow I can do it much faster!" "That's much too expensive an insert it's just not a possibility." 8
Tangential milling Material removal rate Cutting edge diameter Ds [mm] Number of effective teeth z Cutting speed Vc [m/min] Feed rate per tooth fz [mm] Average chip thickness hm [mm] Speed n [rpm] Feed rate Vf [mm/min] Cutting width ae [mm] Cutting depth ap [mm] 9
Tangential milling Material removal rate Which parameter is considered especially important? Which parameter is crucial? When evaluating a tool, it is crucial that all parameters are taken into account. The productivity, also known as the material removal rate, is the resulting parameter. 10
Tangential milling Material removal rate The material removal rate, expressed as Q in formulas, refers to the volume removed in the form of chips over a certain time during material-removing machining processes. In production technology, the material removal rate is a significant factor as it is used as the basis for measuring and rating the productivity of tools and machines. The aim of many developments in the field of tools and machine tools is to improve the material removal rate by increasing the cutting speed or feed rate. Source: Translation of German Wikipedia page 11
Tangential milling Material removal rate Q = side contact x cutting depth x feed rate 1000 Q = ae [mm] x ap [mm] x Vf [mm/min] 1000 Q = cm³/min 12
Tangential milling Material removal rate: example Machining example: Machine: Heller FT8000 Clamping: Machine vice, rigid Workpiece: Block material Material: 42CrMo4 Tensile strength: 1000 N/mm² Cutting edge diameter: 63 mm Number of effective cutting edges: 8 13
Tangential milling Special solutions Special tools Based on standard tools Modified tool solutions Drawing-specific Individually tailored to particular tool usage Comprehensive approach Clamping Geometry Substrate Microgeometry Coating Process Resources Process Mapping
Tangential milling Special solutions: example Cutting width Basic diagram
Tangential milling Summary An R409 indexable insert can be used to equip all milling cutter types used in the M409 system (plus L409 in the case of side(disc) milling cutters) The M406 system can be used for smaller dimensions A high material removal rate can be generated with both systems Special solutions require in-depth consideration Interplay between workpiece, workpiece clamping, material, speed/power of machine
Tangential milling Thank you for your attention