Technical Guidance References

Transcription

1 Technical Guidance 9 to 39 Technical Guidance Turning Edition Milling Edition 5 Endmilling Edition 9 Drilling Edition 22 SUMIBORO Edition 27 SI Unit Conversion List 3 Steel and on-ferrous Metal Symbols Chart () 32 Steel and on-ferrous Metal Symbols Chart (2) 33 Hardness Scale Comparison Chart 34 Standard of Tapers 35 Dimensional Tolerances for Regularly Used Fits 36 Dimensional Tolerances and Fits 38 Finished Surface Roughness 39 9

2 Technical Guidance Basics of Turning Turning Edition Calculating Cutting Speed () Calculating rotation speed from cutting speed f Calculating Power Requirement n = (Ex.) v c =5m/min, D m =mm n =, 5 = 478 (min - ) 3.4 n : Spindle speed (min - ) v c : Cutting speed (m/min) D m : Diameter of work piece (mm) π : 3.4 (2) Calculating cutting speed from rotational speed v c =, v c π D m π D m n, Refer to the above table ødm n ap Feed Direction n : Spindle speed (min - ) v c : Cutting speed (m/min) f : Feed rate (mm/rev) a p : Depth of cut (mm) D m : Diameter of work piece (mm) P c = H= P c.75 v c f a p k c 6 3 η RoughValue of kc P c : et power requirement (KW) v c : Cutting speed (m/min) f : Feed rate (mm/rev) a p : Depth of cut (mm) k c : Specific cutting force (MPa) H : Required horsepower (HP) η : Machine efficiency (.7 to.85) Aluminium: 8MPa General Steel: 2,5 to 3,MPa Cast Iron:,5MPa Cutting Force Relation Between Cutting Speed and Cutting Force Relation Between Feed Rate and Specific Cutting Force (For Carbon Steel) F c : Principal force F f : Feed force F p : Back force Calculating Cutting Force P = k c q, = k c a p f, Fc Fp Ff P : Cutting force (k) k c : Specific cutting force (MPa) q : Chip area (mm 2 ) a p : Depth of Cut (mm) f : Feed Rate (mm/rev) Principal Force (),6 8 Rake angle: Rake angle: Cutting Speed (m/min) Relation Between Rake Angle and Cutting Force Principal Force () 2,8 2,4 2,,6 2 2 Rake Angle (Degree) Specific Cutting Force (MPa) 8, 6, 4, 2, Traverse Rupture Strength 8MPa 6MPa 4MPa Feed Rate (mm/rev) When feed rate decreases, specific cutting force increases. Machined Surface Roughness Relation Between ose Radius and Cutting Force Theoretical Surface Finish h = f RE h : Theoretical surface roughness (mm) f : Feed rate (mm/rev) RE : ose radius (mm) RE Actual Surface Roughness Steel: Theoretical surface finish x.5 to 3 Cast iron: Theoretical surface finish x 3 to 5 f h Ways to Improve Machined Surface Roughness () Use an insert with a larger nose radius. (2) Optimise the cutting speed and feed rate so that built-up edge does not occur. (3) Select an appropriate insert grade. (4) Use wiper insert Cutting Force () Principal force Feed force Back force ose Radius (mm) Large nose radius increases back force. Work : SCM44(38HS) Inserts : TGA224 SS Holder : PTGR Cutting Conditions : v c =m/min a p =4mm f =.45mm/rev

3 Turning Edition Technical Guidance Tool Failures and Tool Life Forms of Tool Failures Cat. o. ame of Failure Cause of Failure () to (5) Flank Wear Resulting from Mechanical Causes Resulting from Chemical Reactions (6) (7) (8) (9) () () Chipping Fracture Crater Wear Plastic Deformation Thermal Crack Built-up Edge Due to the scratching effect of hard grains contained in the work material. Fine breakages caused by high cutting loads or chattering. Large breakage caused by the impact of excessive mechanical forces acting on the cutting edge. Swaft chips removing tool material as it flow over the top face at high temperatures. Cutting edge is depressed due to softening at high temperatures. Fatigue from rapid, repeated heating and cooling cycles during machining. Adhesion or accumulation of extremely-hard work material on the cutting edge. Tool Wear Forms of Tool Wear Flank Wear Crater Wear Poor surface finish Face flank wear V2 Edge wear VC Poor machining accuracy, Burrs occur Bad chip control cutting edge fracture Crater wear KT Crater Wear Flank Wear Flank average wear VB Burrs occur Side flank wear V Higher cutting force Flank Wear Width VB (mm) Initial wear Steady wear Cutting Time T (min) Sudden increase in wear Flank Wear Width KT (mm) Cutting Time T (min) Wear increases rapidly right after cutting Wear increases in proportion to the starts, it then progresses at a moderate and cutting time. proportionate pace up to a certain point where it suddenly increases rapidly again. Tool Life (V-T) This double logarithm graph shows the relative tool life of the specified wear over a range of cutting speeds on the X-axis, and the cutting speed along the Y-axis. Flank Wear Crater Wear Tool Wear Flank Wear Width (mm) vc vc vc vc Cutting Time (min) Crater Wear Depth (mm) vc vc vc vc Cutting Time (min) Tool Life Cutting Speed (m/min) vc vc vc vc Cutting Speed (m/min) vc vc vc vc Tool Life (min) Tool Life (min)

4 Technical Guidance Tool Failure and Remedies Turning Edition Insert Failure and Countermeasures Type of Insert Failure Cause Countermeasures Flank Wear Grade lacks wear resistance. Cutting speed is too fast. Feed rate is far too slow. Select a more wear-resistant grade. P3 P2 P K2 K K Use an insert with a larger rake angle. Decrease the cutting speed Increase feed rates. Crater Wear Grade lacks crater wear resistance. Rake angle is too small. Cutting speed is too fast. Feed rate and depth of cut are too large. Select a more crater-wear-resistant grade. Use an insert with a larger rake angle. Change the chipbreaker. Decrease the cutting speed Reduce feed rates and depth of cut. Chipping Grade lacks toughness. Cutting edge breaks off due to chip build-up. Cutting edge lacks toughness. Feed rate and depth of cut are too large. Select a tougher grade. P P2 P3 K K K2 Increase amount of honing on cutting edge. Reduce rake angle. Reduce feed rates and depth of cut. Fracture Grade lacks toughness. Cutting edge lacks toughness. Holder lacks toughness. Feed rate is too fast. Depth of cut is too large. Select a tougher grade. P P2 P3 K K K2 Select a chipbreaker with a strong cutting edge. Select a holder with a larger approach angle. Select a holder with a larger shank size. Reduce feed rates and depth of cut. Welding or Built-up Edge Inappropriate grade selection. Dull cutting edge. Cutting speed is too slow. Feed rate is too slow. Select a grade with less affinity to the work material like coated carbide or cermet grades. Select a grade with a smooth coating. Use an insert with a larger rake angle. Reduce amount of honing. Increase cutting speeds. Increase feed rates. Plastic Deformation Grade lacks thermal resistance. Cutting speed is too fast. Feed rate is too fast. Depth of cut is too large. ot enough cutting fluid. Select a more crater-wear-resistant grade. Use an insert with a larger rake angle. Decrease the cutting speed Reduce feed rates and depth of cut. Supply sufficient amount of coolant. otch Wear Grade lacks wear resistance. Rake angle is too small. Cutting speed is too fast. Select a wear-resistant grade. P3 P2 P K2 K K Use an insert with a larger rake angle. Alter depth of cut to shift the notch location. 2

5 Turning Edition Technical Guidance Chip Control Type of Chip Generation Spiralling Shearing Tearing Cracking Type of Chip Control Depth Shape Work material Work material Work material Work material Chip Types Large Condition Application Influence Factor Continuous chips with good surface finish. Steel, Stainless steel Chip is sheared and separated by the shear angle. Steel, Stainless steel (Low speed) Easy Large Small Fast Work deformation Rake angle D.O.C. Cutting speed Chips appear to be torn from the surface. Steel, Cast iron (very low speed, very small feed rate) Difficult Small Large Slow Chips crack before reaching the cutting point. Cast iron, Carbon Evaluation Small C Lathe (For Automation) General Lathe (For Safety) Good: C type, D type A type: Twines around the tool or workpiece, damages the machined surface and affects safety. Poor B type: Causes problems in the automatic chip conveyor and chipping occurs easily. E type: Causes spraying of chips, poor machined surface due to chattering, chipping, large cutting force and high temperatures. Factor of Improvement Chip Control () Increase Feed Rate (f) t f t 2 f 2 ff 2 f thent 2 t Depth of Cut (mm) When feed rate increases, chips become thick and chip control improves Feed Rate (mm/rev) (2) Decrease Side Cutting Edge (θ ) 2 f t t 2 f 2 thent 2 t Even if feed rate is the same, smaller side cutting edge angle makes chips thick and chip control improves. Side Cutting Edge Angle Feed Rate (mm/rev) (3) Decrease ose Radius (RE) f RE Large nose radius f 2 t t 2 RE2 Small nose radius RERE2RE thent 2t Even if feed rate is the same, a smaller nose radius makes chip thick and chip control improves. * Cutting force increases in proportion with the length of the contact surface. Therefore, a larger nose radius increases back force which induces chattering. With the same feed rate, a smaller nose radius produces a rougher surface finish. ose Radius (mm) Depth of Cut (mm) 3

6 Technical Guidance Basics of Threading Turning Edition Thread Cutting Methods Cutting Method Radial Infeed Leading Edge Feed Dir. Trailing Edge Direction of Cut Characteristics Most common threading technique, used mainly for small pitch threads. Easy to change cutting conditions such as depth of cut, etc. Longer contact points lead to more chatter. Difficult to control chip evacuation. Damage on the trailing edge gets larger faster. Flank Infeed Effective for large pitch threads and blemish-prone work material surfaces. Chips evacuate from one side for good chip control. The trailing edge side is worn, and therefore the flank is easily worn. Corrected Flank Infeed Effective for large pitch threads and blemish-prone work material surfaces. Chips evacuate from one side for good chip control. Inhibits flank wear on trailing edge side. Alternating Flank Infeed Effective for large pitch threads and blemish-prone work material surfaces. Wears evenly on right and left cut edges. Since both edges are used alternatively, chip control is sometimes difficult. Troubleshooting for Threading Failure Cause Countermeasures Excessive Cutting Edge Wear Tool material Select a more wear-resistant grade Cutting Edge Failure Uneven Wear on Right and Left Sides Cutting condition Insert attachment Cutting condition Decrease the cutting speed Optimise coolant flow and density Change the number of passes. Check whether the cutting edge inclination angle is appropriate for the screw lead angle. Check whether the tool is mounted properly. Change to corrected flank infeed or alternating flank infeed Chipping Cutting condition If caused by a built-up edge, increase cutting speed Breakage Poor Surface Roughness Packing of chips Cutting condition Cutting condition Supply enough amount of coolant to the cutting edge. Increase the number of passes while decreasing the depth of cut per pass. Use different tools for roughing and finishing applications. If blemished due to low-speed machining, increase the cutting speed. If chattering occurs, decrease the cutting speed. If the depth of cut of the final pass is small, make it larger. 4 Shape and Accuracy Tool material Select a more wear-resistant grade Inappropriate cutting edge inclination angle Select a correct shim to secure relief on the side of the insert. Inappropriate Thread Shape Insert attachment Check whether the tool is mounted properly. Shallow Thread Depth Small depth of cut Check cutting depth Tool wear Check damage to the cutting edge.

7 Parts of a Milling Cutter Milling Edition Technical Guidance Basics of Milling Body diameter Boss diameter Hole diameter Keyway width Body Keyway depth Corner angle Ring Axial rake angle Reference ring Cutter height Approach Angle Chip pocket Clamp bolt Face angle relief Indexable insert Cutter diameter (nominal diameter) True rake angle Peripheral relief angle Cutting edge inclination angle A Clamp Locator A Reference ring Radial rake angle Face cutting edge angle Face cutting edge (Wiper cutting edge) External cutting edge (Principal cutting edge) Chamfer Milling Calculation Formulas Calculating Cutting Speed v c = n = π DC n, Calculating Feed Rate v f =f z z n f z =, v c π DC v f z n v c : Cutting speed (m/min) π : 3.4 DC : Cutter diameter (mm) n : Rotational speed (min - ) v f : Feed rate per minute (mm/min) f z : Feed rate per tooth (mm/t) z : umber of teeth ap fz DC Cutter n n Work material vf vf Power Requirement P c = a e a p v f k c = Q k c 6 6 η 6 3 η Horsepower Requirement P H = c.75 Chip Removal Amount Q = a e a p v f, P c : Power requirement (kw) H : Required horsepower (HP) Q : Chip removal amount (cm 3 /min) a e : Cutting width (mm) v f : Feed rate (mm/min) a p : Depth of cut (mm) k c : Specific cutting force (MPa) Rough value Steel: 2,5 to 3,MPa Cast iron:,5mpa Aluminium: 8MPa η : Machine efficiency (about.75) Relation Between Feed Rate, Work Material, Specific Cutting Force Specific Cutting Force (MPa) Symbol Work Material Alloy Steel Carbon Steel Cast Iron Aluminium Alloy () (2) (3)..4 2 Figures in table indicate these characteristics. Alloy steel and carbon steel: Traverse rupture strength σ B(GPa) Cast iron: Hardness HB Feed Rate (mm/t) 5

8 Technical Guidance Basics of Milling Milling Edition Functions of the Various Cutting Angles Description Symbol Function Effect () (2) Axial rake angle Radial rake angle A.R. R.R. Determines chip removal direction, builtup edge, cutting force Available in positive to negative (large to small) rake angles; Typical combinations: Positive and egative, Positive and Positive, egative and egative (3) Approach angle A.A. Determines chip thickness, chip removal direction Large: Thin chips and small cutting force (4) True rake angle T.A. Effective rake angle Positive (Large): Excellent machinability Low cutting edge strength. egative (Small): Strong cutting edge and easy chip adhesion. (5) Cutting edge inclination angle I.A. Determines chip control direction Positive (Large): Excellent chip control and small cutting force. Low cutting edge strength. (6) Face cutting edge angle F.A. Determines surface roughness Small: Improved surface roughness. (7) Relief angle Determines edge strength, tool life, chattering True Rake Angle Chart (T.A) True Rake Angle T.A Approach Angle A.A (Ex.) () A.R (Axial rake angle) = + (2) R.R (Radial rake angle) = 3 (3) A.A (Approach angle) = 6 -> T.A. (True rake angle) = 8 (4) Radial Rake Angle R.R <Formula> tan T.A=tan R.R cos A.A + tan A.R sin A.A Axial Rake Angle A.R Axial Rake Angle A.R Inclination Angle (I.A) Chart Inclination Angle I.A Approach Angle A.A (Ex.) () A.R (Axial rake angle) (2) R.R (Radial rake angle) (3) A.A (Approach angle) = =+5 = 25 <Formula> tan I.R=tan A.R cos A.A tan R.R sin A.A Radial Rake Angle R.R -> I (Inclination angle) = 5 (4) Rake Angle Combination Edge Combination and Chip Removal Double Positive Type egative - Positive Type Double egative Type A.A (5 to 3 ) A.A (3 to 45 ) A.A (5 to 3 ) Positive Positive egative A.R: Axial rake angle R.R: Radial rake angle A.A: Approach angle : Chip and removal direction : Rotation Positive egative egative Advantages Good cutting action Excellent chip removal and cutting action Double-sided inserts can be used and higher cutting edge strength Disadvantages Application Lower cutting edge strength and only single-sided inserts can be used For general milling of steel and low rigidity work piece Only single-sided inserts can be used For Steel, Cast iron, Stainless steel, Alloy steel Dull cutting action For light milling of cast iron and steel Series DPG Type WGX Type, UFO Type DGC Type, DX Type Chips (Ex.) Work material: SCM435 v c=3m/min f z =.23mm/t a p =3mm 6

9 Milling Edition Technical Guidance Basics of Milling Relation Between Engagement Angle and Tool Life Work material feed direction V f Cutting Width W DC Engagement angle E Insert Rotation The Engagement angle denotes the angle at which the full length of the cutting edge comes in contact with the work material, with reference to the feed direction. The larger E is, the shorter the tool life. To change the value of E: ) Increase the cutter size. 2) Shift the position of the cutter. Relation to Cutter Diameter Relation to Cutter Position Relation to Tool Life Large Diameter Tool Life (Milling Area) (m 2 ) f f DC E Small E Small.4.3 S5C Engagement Angle Small Diameter Tool Life (Milling Area) (m 2 ) f f DC E Large E Large FC Engagement Angle Relation between the number of simultaneously engaged cutting edges and cutting force: ormally, cutting width is considered to be appropriate with 7 to 8% of the cutter diameter engaged as shown in example d). However, this may not apply due to the actual rigidity of the machine or work piece, and machine horsepower. a) b) c) d) e) Cutting force Cutting force Cutting force Time Time Time Time Time Work material Cutting force Cutting force Cutter or edge in contact at same time. Only edge in contact at any time. or 2 edges in contact. 2 edge in contact at any time. 2 to 3 edges in contact. To Improve Surface Roughness Surface roughness without wiper flat Influence of different face angles on surface finish () Inserts with wiper flat When all the cutting edges have wiper flats, a few teeth are intentionally elevated to play the role of a wiper insert. Insert equipped with straight wiper flat (Face angle: 5' - ) Insert equipped with curved wiper flat (Curvature R5 (example)) (2) Wiper insert assembling system A system to protrude one or two inserts (wiper inserts) with a smooth curved edge just a little beyond the other teeth to wipe the milled surface. (Applies to WGC, RF types, etc.) HC Surface roughness with straight wiper flat HF h: Projection value of wiper insert Fc:.5mm Wiper insert Al:.3mm HW h f : Feed rate per revolution (mm/rev) ormal teeth HC HW Hc: Surface roughness with only normal teeth Hw: Surface roughness with wiper insert (A) (B) Effects of having wiper insert (example) (C) (D) (Only normal teeth) Roughness (µm) (With wiper insert) Roughness (µm) Feed rate per tooth Feed rate per tooth Feed rate per tooth, 2 Feed rate per tooth 2,, 2 Feed rate per rev. Work : SCM435 Cutter: DPG56R (Single tooth) vc= 54m/min fz =.234mm/t ap = 2mm Face Cutting Edge Angle (A): 28' (B): 6' Work : FC25 Cutter: DPG4R Insert : SPCH42R Face run-out :.5mm Radial run-out:.4mm vc = 5m/min fz =.29mm/t (.45 mm/rev) (C) : Only normal teeth (D) : With wiper insert 7

10 Technical Guidance Troubleshooting for Milling Milling Edition Tool Failure and Remedies Failure Basic Remedies Remedy Examples Excessive Flank Wear Tool Material Cutting Conditions Select a more wear resistant grade. Carbide P3 P2 Coated K2 K Cermet Reduce cutting speeds. Increase feed rate. Recommended insert grades Steel Cast Iron on-ferrous Alloy T25A, T45A ACK (Coated Carbide) Finishing DA (SUMIDIA) (Cermet) B7 (SUMIBORO) Roughing ACP (Coated Carbide) ACK2 (Coated Carbide) DL (Coated Carbide) Excessive Crater Wear Tool Material Cutting Conditions Select a crater-resistant grade. Reduce cutting speeds. Reduce depth-of-cut and feed rate. Recommended insert grades Steel Cast Iron on-ferrous Alloy T25A, T45A Finishing ACK (Coated Carbide) DA (SUMIDIA) (Cermet) Roughing ACP (Coated Carbide) ACK2 (Coated Carbide) DL (Coated Carbide) Cutting Edge Failure Chipping Tool Material Change to tougher grades. P P2 P3 K K K2 Tool Design Select a negative-positive cutter configuration with a large peripheral cutting edge angle (small approach angle). Reinforce the cutting edge (Honing). Select a strong edge insert (G H). Cutting Conditions Reduce feed rates. Recommended insert grades Steel Cast Iron Finishing ACP2 (Coated Carbide) ACK2 (Coated Carbide) Roughing ACP3 (Coated Carbide) ACK3 (Coated Carbide) Recommended cutter: SEC-WaveMill WGX Type Cutting conditions: Refer to H2 Breakage Tool Material If it is due to excessive low speeds or very low Recommended insert grades feed rates, select an adhesion resistant grade. If it is due to thermal cracking, select Steel Cast Iron a thermal impact resistant grade. Roughing ACP3 (Coated Carbide) ACK3 (Coated Carbide) Tool Design Select a negative-positive (or negative) cutter configuration with a large peripheral cutting edge angle (small approach angle). Recommended cutter: SEC-WaveMill WGX Type Reinforce the cutting edge (Honing). Insert thickness: mm Select a stronger chipbreaker (G H) Increase insert size (Thickness in particular). Insert type: Standard Strong edge type Cutting Select appropriate conditions with Conditions regards to the particular application. Cutting conditions: Refer to H2 Unsatisfactory Machined Surface Finish Tool Material Tool Design Cutting Conditions Select an adhesion resistant grade. Carbide Cermet Improve axial runout of cutting edges. Use a cutter with less runout Attach correct inserts. Use wiper inserts. Use special purpose cutters designed for finishing. Increase cutting speeds Recommended insert grades Steel Cast Iron on-ferrous Alloy General Purpose Finishing Cutter Insert Cutter Insert WGX type* ACP2 (Coated Carbide) WGX type T45A (Cermet) DGC type ACK2 (Coated Carbide) FMU type B7 (SUMIBORO) RF type* H (Carbide) DL (Coated Carbide) RF type DA (SUMIDIA) * marked cutters can be fitted with wiper inserts. Others Chattering Unsatisfactory Chip Control Edge Chipping On Workpiece Tool Design Select a cutter with sharp cutting edges. Use an irregular pitched cutter. Cutting Conditions Reduce feed rates. Others Improve workpiece and cutter clamp rigidity. Recommended cutter For Steel: SEC-WaveMill WGX Type For Cast Iron: SEC-Sumi Dual Mill DGC Type For on-ferrous Alloy: High Speed cutter for Aluminium RF type Tool Design Select cutter with good chip removal features. Recommended cutter: SEC-WaveMill WGX Type Reduce number of teeth. Enlarge chip pocket. Tool Design Cutting Conditions Increase the peripheral cutting edge angle (decrease the approach angle). Select a stronger chipbreaker (G L). Reduce feed rates. Recommended cutter: SEC-WaveMill WGX Type Burr On Workpiece Tool Design Cutting Conditions Select a cutter with sharp cutting edges. Recommended cutter: SEC-WaveMill WGX Type+ FG Breaker Increase feed rates. DGC Type + FG Breaker Select an insert designed for low burr. 8

11 Endmilling Edition Technical Guidance Basics of Endmilling Parts of an Endmill Diameter Body eck Shank Cutter sweep eck diameter eck length Length of cut Shank length Shank diameter Center hole Land width Relief width Margin width Margin Radial relief Radial primary relief angle Radial secondary clearance angle Overall length Center Cut With Center Hole Land width Land Rake face Rake angle Flute Heel Helix angle Corner End cutting edge Radial cutting edge End gash Rounded flute bottom Center hole Flute depth Web thickness Chip pocket Axial primary relief angle Axial secondary clearance angle Concavity angle of Ball radius end cutting edge (*) * Center area is lower than the periphery Calculating Cutting Conditions (Square Endmill) Calculating Cutting Speed v c = π x DC x n, n=, x v c π xdc Side milling Slotting (Ball Endmill) Calculating Feed Rate Per Revolution and Per Tooth v f = n x f f= v f n v f = n x f z x z f z = f = z Calculating otch Width (D ) v f n x z ap a DC DC ap D = 2 x2 x RE x a p a p 2 Cutting speed and feed rate (per revolution and per tooth) are calculated using the same formula as square endmill. RE pf Pick feed D ap Depth of cut ap DC pf RE D v c : Cutting speed (m/min) π : 3.4 DC : Endmill diameter (mm) n : Spindle speed (min - ) v f : Feed rate (mm/min) f : Feed rate per revolution (mm/rev) f z : Feed rate per tooth (mm/t) z : umber of teeth a p : Axial Depth of Cut (mm) a e : Radial Depth of Cut (mm) RE : Ballnose Radius 9

12 Technical Guidance Basics of Endmilling Endmilling Edition Up-cut and Down-cut Side Milling Slotting fz Work material Work Feed Direction (a) Up-cut fz Work material Work Feed Direction (b) Down-cut Work Feed Direction fz Work material Up-cut Down-cut Work material Work Feed Direction Work material Work Feed Direction (a) Up-cut (b) Down-cut Wear Amount Surface Roughness Condition Flank Wear Width (mm) Up-cut Down-cut Cutting Length (m) Rz (μm) Feed Dir. Up-cut Down-cut Vertical Dir. Down-cut Up-cut Work: S5C Endmill: GSX2C-2D (ømm, 2 teeth) Cutting Conditions: v c =88m/min (=28min - ) v f =56mm/min (f z =.mm/t) a p =5mm a e =.5mm Side Milling Dry,Air Relation Between Cutting Condition and Deflection Side Milling Slotting Endmill Specifications Work: Pre-hardened steel (4HRC) Cutting Conditions: v c =25m/min a p =2mm a e =.8mm Work: Pre-hardened steel (4HRC) Cutting Conditions: v c =25m/min a p =8mm a e =8mm Up-cut Down-cut Feed rate Feed rate Feed rate Feed rate Cat. o. umber of Teeth Helix Angle.6mm/rev.mm/rev.5mm/rev.3mm/rev Style Style Style Style Up-cut Down-cut Up-cut Down-cut Up-cut Down-cut Up-cut Down-cut GSX28S-2D GSX48S-2D Cutting surface Reference surface Results The tool tip tends to back off with the down-cut. The side of the slot tends to cut into the up-cut side toward the bottom of the slot. 4 teeth offers more rigidity and less backing off. 4 teeth offers higher rigidity and less deflection. 2

13 Endmilling Edition Technical Guidance Troubleshooting for Endmilling Troubleshooting for Endmilling Failure Cause Remedies Excessive Wear Cutting Conditions Tool Shape Tool Material Cutting speed is too fast Feed rate is too fast The flank relief angle is too small Insufficient wear resistance Decrease cutting speed and feed rate. Change to an appropriate flank relief angle Select a substrate with more wear resistance Use a coated tool Cutting Edge Failure Chipping Cutting Conditions Machine Area Feed rate is too fast Cutting depth is too deep Tool overhang is too long Work clamps are weak Tool is not firmly attached Decrease cutting speed. Reduce depth of cut Adjust tool overhang for correct length Clamp the work piece firmly Make sure the tool is seated in the chuck properly Tool Fracture Cutting Conditions Tool Shape Feed rate is too fast Cutting depth is too deep Tool overhang is too long Cutting edge is too long Web thickness is too small Decrease cutting speed. Reduce depth of cut Reduce tool overhang as much as possible Select a tool with a shorter cutting edge Change to more appropriate web thickness Shoulder Deflection Cutting Conditions Tool Shape Feed rate is too fast Cutting depth is too deep Tool overhang is too long Cutting on the down-cut Helix angle is large Web thickness is too thin Decrease cutting speed. Reduce depth of cut Adjust tool overhang for correct length Change directions to up-cut Use a tool with a smaller helix angle Use a tool with the appropriate web thickness Unsatisfactory Machined Surface Finish Cutting Conditions Feed rate is too fast Packing of chips Decrease cutting speed. Use air blow Use an insert with a larger relief pocket. Others Chattering Cutting Conditions Tool Shape Machine Area Cutting speed is too fast Cutting on the up-cut Tool overhang is too long Rake angle is large Work clamps are weak Tool is not firmly attached Decrease the cutting speed Change directions to down-cut Adjust tool overhang for correct length Use a tool with an appropriate rake angle Clamp the work piece firmly Make sure the tool is seated in the chuck properly Packing of Chips Cutting Conditions Tool Shape Feed rate is too fast Cutting depth is too deep Too many teeth Packing of chips Decrease cutting speed. Reduce depth of cut Reduce number of teeth Use air blow 2

14 Technical Guidance Basics of Drilling Parts of a Drill Margin width Height of point Drilling Edition Leading edge Back taper Margin Body clearance Flank Lead eck Taper shank Tang Land width Chisel edge angle Flute width Cutting edge Flute Drill diameter Cutting edge Outer corner Point angle Heel Helix angle Body clearance Rake face Flute length eck length Shank length Tang thickness Chisel edge corner Chisel edge Depth of body clearance Overall length Straight shank Tang thickness Chisel edge length Diameter of body clearance Relief angle Rake angle Tang length Web thickness Web thinning Web Cutter sweep A:B or A/B = Flute width ratio Point Angle and Force Minimum Requirement Relief Angle Relation Between Edge Treatment and Cutting Force f: Feed rate (mm/rev) 8, Point angle (small) Point Angle and Burr Point angle (large) When point angle is large, thrust becomes large but torque becomes small. DC DX Ѳx πdx Ѳ πdc f Ѳx = tan πdx * Large relief angle is needed at the center of the drill. Web Thickness and Thrust f Torque ( m) Thrust () 6, 4, 2, Feed Rate (mm/rev) Burr Height (mm) Feed Rate (mm/rev) Work: SS4 Cutting Speed v c=5m/min When point angle is large, burr height becomes low. Thrust Thrust Removed Web thinning decreases the thrust concentrated at the chisel edge, makes the drill edge sharp, and improves chip control Feed Rate (mm/rev) Drill : Multi-drill KDS25MAK Width :.5mm.23mm Work : S5C (23HB) Cutting Conditions : v c =5m/min, Wet 22 Decrease Chisel Width by Thinning Typical types of thinning S type type X type S type: Standard type used generally. type: Suitable for thin web drills. X type: For hard-to-cut material or deep hole drilling. Drill starts easier.

15 Drilling Edition Technical Guidance Basics of Drilling Reference of Power Requirement and Thrust Cutting Condition Selection Control Cutting Force for Low Rigid Machine High Speed Machining Recommendation Power (kw) f: Feed rate (mm/rev) Work material: S48C (22HB) The following table shows the relation between edge treatment width and cutting force. If a problem caused by cutting force occurs, reduce either the feed rate or the edge treatment width. Cutting Conditions f=.3 Diameter ødc (mm) f=.2 f=..5mm Edge Treatment Width.5mm v c (m/min) f(mm/rev) Torque ( m) Thrust () Torque ( m) Thrust () , , ,52 9.4, ,32 7.6, ,64 5.2, Drill : ømm Work : S5C 23HB If there is surplus capacity with enough machine power and sufficient rigidity, adopting higher efficiency conditions would improve the tool life; however, sufficient amount of coolant must be supplied. Margin Flank facerake face Thrust () 2,, 8, 6, 4, 2, Wear Example f=.3 f=.2 f= Diameter ødc (mm) v c =6m/min v c =2m/min Work : S5C (23HB) Cond.: f =.3mm/rev H = 5mm Life : 6holes (Cutting length: 3m) Explanation of Margins (Difference between single and double margins) Single Margin (2 guides: circled parts) Double Margin (4 guides: circled parts) Shape used on most drills 4-point guiding reduces hole bending and undulation for improved stability and accuracy during deep hole drilling. 23

16 Technical Guidance Basics of Drilling Drilling Edition Run-out Accuracy For the run-out accuracy of web-thinned drills, not only the difference in lip height (B) but also the runout after thinning (A) is important. (A): The run-out accuracy of thinning point (B): The difference of the lip height Hole Expansion (mm) MDS4MK S5C vc5m/min f3mm/rev (Units: mm) Center run-out (A) (mm) Peripheral run-out (B) (mm) Peripheral Run-out Accuracy when Tool Rotates When the tool rotates The peripheral run-out accuracy of the drill mounted on the spindle should be controlled within.3mm. If the run-out exceeds the limit, the drilled hole will also become large causing an increase in the horizontal cutting force, which may result in drill breakage. Run-out: within.3mm Peripheral Run-out (mm).5.9 Hole Expansion Cutting Force*.5(mm) (kg) * Horizontal cutting force. Drill: MDS2MK Work material: S5C (23HB) Cutting Conditionsc=5m/min, =.3mm/rev, =38mm Water soluble coolant When the work material rotates ot only the peripheral run-out at the drill edge (A) but also the concentricity at (B) should be controlled within.3mm. Chuck.3mm Run-out: within.3mm Influence of Work Material Surface Work material with slanted or uneven surface If the surface of the hole entrance or exit is slanted or uneven, decrease the feed rate to /3 to /2 of the recommended cutting condition. (Entrance) (Exit) How to Use a Long Drill Problem When using a long drill (XHGS type), DAK type drill, SMDH-D type drill, or SMDH-2.5D type drill at high rotation speeds, the run-out of the drill tip may cause a deviation of the entry point as shown on the right, bending the drill hole and resulting in drill breakage. Hole bend Position shift Remedies Method Step Step 2 Step 3 Short drill xdc pilot hole (same dia.) n= to 3min Method 2 * Low rotational speed minimises centrifugal forces and prevents drill bending. Step 2 to 3mm Step 2 2 to 3mm Drilling under recommended condition (n= to 3min ) f=.5 to.2mm/rev Drilling under recommended condition 24

17 Drilling Edition Technical Guidance MultiDrill Usage Guidance Drill Maintenance Using Cutting Oil () Collet Selection and Maintenance Ensure proper chucking of drills to prevent vibration. Collet chucks (thrust bearing type) provide strong and secure grip force. When replacing drills, regularly remove cutting debris inside the collet by cleaning the collet and the spindle with oil. Repair marks with an oilstone. (2) Drill Installation The peripheral run-out of the drill mounted on the spindle should be controlled within.3mm. Do not chuck on the drill flute. If drill flute inside the holder, chip removal will be obstructed thus causing damage to the drills. Drill chucks and keyless chucks are not suitable for MultiDrills as they have a weaker grip force. Collet Chuck Collet Collet Edge run-out to be within.3mm. Drill Chuck If there are marks, repair with an oilstone or change to a new one. Do not grip on the drill flute. () Choosing of Cutting Oil If cutting speed is more than 4m/min, cutting oil JISW type 2 is recommended for its good cooling effect & chip removal ability as it is highly soluble. If cutting speed is below 4m/min and longer tool life is a priority, non-water cutting oil JISA type 2, an activated sulphuric chloride oil, is recommended for its lubricity. * on-water soluble oil may be flammable. To prevent fire, a substantial amount of oil should be used to cool the component so that smoke or heat will not be generated. (2) Supply of Coolant If using an external supply of coolant, fill a substantial amount from the inlet. Oil pressure range:.3 to.5 MPa, oil level range: 3 to /min. If using an internal supply of coolant (Ex: HK Type) for holes For holes ø4 or smaller, the oil pressure must be at least.5mpa to ensure a sufficient supply of coolant. holes ø6 or larger:.5 to. MPa for hole depths below 3 times the drill diameter, and to 2 MPa or more for hole depths more than 3 times the diameter. External supply of coolant Vertical drilling Use high pressure at entrance Horizontal drilling Easy usage Use high pressure at entrance Internal supply of coolant Coolant supply holder Machine internal supply Calculation of Power Consumption and Thrust Work Clamping Calculating Cutting Speed v c = n= π x DC x n,, x v c π x DC DC n Hole Depth High thrust forces occur during high-efficiency drilling. Therefore, the workpiece must be supported to prevent fracture caused by bending. Also, large torques and horizontal cutting forces occur. Therefore, the workpiece must be clamped firmly enough to withstand them. Bending Especially large drills Fracture Calculating Feed Rate Per Revolution and Per Tooth v c : Cutting Speed (m/min) v f = n x f f= v π : Circular Constant 3.4 f n DC : Drill Diameter (mm) n : Spindle Speeds (min - ) v f : Feed Rate (mm/min) Calculation of Cutting Time f : Feed Rate per Revolution (mm/rev) H H : Drilling Depth (mm) T= v f T : Cutting Time (min) HB : Brinell Hardness Calculation of Power Consumption and Thrust Power Consumption(kW)=HB DC.68 v c.27 f.59 /36, Thrust()=.24 HB DC.95 f * When designing the machine, an allowance of.6 x Power Consumption and.4 x Thrust should be given. Drill Regrinding When to regrind When one or two feed marks (lines) appear on the margin, when corner wear reaches the margin width, or when small chipping occurs, it indicates that the drill needs to be sent for regrinding. How and where to regrind We recommend applying regrinding and recoating. Recoating is recommended to prevent shortening of tool life. ote, ask us or an approved vendor to recoat with our proprietary coating. Regrinding on your own Customers regrinding their own drills can obtain MultiDrill Regrinding Instructions from us directly or your vendor. Tool life determinant to 2 feed marks Appropriate tool life Excessive marks Over-used 25

18 Technical Guidance Tool Failure and Remedies Drilling Edition Troubleshooting for Drilling Failure Cause Basic Remedies Remedy Examples Excessive Wear on Cutting Edge Inappropriate cutting conditions. Unsuitable cutting fluid. Use higher cutting speeds. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Increase feed rates. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Reduce pressure if using internal coolant..5 MPa or below (external coolant if hole depth is L/D = 2 or less). Use cutting fluid with more lubricity. Use JIS A grade o. or its equivalent. Chisel Point Chipping Off-center starts. Equipment and/or work material lacks rigidity. Cutting edge is too weak. Reduce feed rate at entry point. f=.8 to.2mm/rev Pre-processing to ensure flat contact surface. Use endmill to produce flat surface. Change cutting conditions to reduce resistance. Increase v c and decrease f (reduce thrust). Improve work material clamp rigidity. Increase size of chisel width. Set chisel width from. to.2 mm. Increase amount of honing on cutting edge. Make thinning section of central area.5x current width. Chipping On Peripheral Cutting Edge Inappropriate drilling conditions. Decrease the cutting speed. Refer to the lower limit of recommended conditions listed in the Igetalloy Cutting Tools Catalogue. Reduce feed rate. Refer to the lower limit of recommended conditions listed in the Igetalloy Cutting Tools Catalogue. Unsuitable cutting fluid. Use cutting fluid with more lubricity. Use JIS A grade o. or its equivalent. Drill Failure Equipment and/or work material lacks rigidity. Improve work material clamp rigidity. Cutting edge is too Increase amount of honing on cutting edge. Make peripheral cutting edge.5x current width. weak. Reduce the amount of front flank angle. Reduce the amount of front flank angle by 2 to 3. Peripheral cutting edge starts cutting first Increase margin width (W margin). Increase margin width by 2 to 3x current width. Cutting interrupted Reduce feed rate. Refer to the lower limit of recommended conditions listed in the Igetalloy Cutting Tools Catalogue. when drilling through Increase amount of honing on cutting edge. Make peripheral cutting edge.5x current width. workpiece. Reduce the amount of front flank angle. Reduce the amount of front flank angle by 2 to 3. Margin Wear Inappropriate drilling conditions. Decrease the cutting speed. Refer to the lower limit of recommended conditions listed in the Igetalloy Cutting Tools Catalogue. Unsuitable cutting fluid. Use cutting fluid with more lubricity. Use JIS A grade o. or its equivalent. Increase coolant supply. If using external coolant, change to internal coolant supply. Latent margin wear. Early regrind to ensure adequate back taper. Regrind margin damage to mm or less. Increase amount of back taper. Make back taper.5/. Unsuitable tool design. Reduce margin width. Decrease margin width to two-thirds of current width. Drill Breakage Chip build-up. Use optimal cutting conditions and tools. Refer to the table of recommended conditions in the Igetalloy Cutting Tools Catalogue. Increase coolant supply. If using external coolant, change to internal coolant supply. Collet clamp lacks strength. Use collet with strong grip force. Replace collet chuck if damaged. Use collet holder one size bigger. Equipment and/or work material lacks rigidity. Improve work material clamp rigidity. Oversized Holes Off-center starts. Reduce feed rate at entry point. f=.8 to.2mm/rev Decrease the cutting speed. Refer to the lower limit of recommended conditions listed in the Igetalloy Cutting Tools Catalogue. Pre-processing to ensure flat contact surface. Use endmill to produce flat surface. Unsatisfactory Hole Accuracy Unsatisfactory Chip Control Poor Surface Finish Holes Are ot Straight Packing Of Chips Long Stringy Chips Drill bit lacks rigidity. Drill bit has run-out Use optimal drill type for hole depth. Refer to the Igetalloy Cutting Tools Catalogue. Improve overall rigidity of drill. Large web with comparatively small flute. Improve drill clamp precision. Replace collet chuck if damaged. Improve drill clamp rigidity. Use collet holder one size bigger. Equipment and/or work material lacks rigidity. Improve work material clamp rigidity. Inappropriate cutting conditions. Increase cutting speeds. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Reduce feed rate. Refer to the lower limit of recommended conditions listed in the Igetalloy Cutting Tools Catalogue. Unsuitable cutting fluid. Use cutting fluid with more lubricity. Use JIS A grade o. or its equivalent. Off-center starts. Increase feed rates. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Drill is not mounted properly. Equipment and/or work material lacks rigidity. Inappropriate drilling conditions. Improve drill clamp precision. Replace collet chuck if damaged. Improve drill clamp rigidity. Use collet holder one size bigger. Improve work material clamp rigidity. Select a double margin tool. Refer to the Igetalloy Cutting Tools Catalogue. Increase cutting speeds. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Increase feed rates. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Poor chip evacuation. Increase the amount or pressure of coolant applied if using internal coolant. Inappropriate drilling conditions. Increase feed rates. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Increase cutting speeds. Refer to the upper limit of the recommended conditions listed the Igetalloy Cutting Tools Catalogue. Cooling effect is too strong. Reduce pressure if using internal coolant. Keep pressure.5 MPa or lower if using internal coolant. Dull cutting edge. Reduce amount of edge honing. Reduce to around two-thirds of current width. 26

19 SUMIBORO Edition Technical Guidance Hardened Steel Machining with SUMIBORO Application Map of the Various Tool Materials Work Materials and their Cutting Speed Recommendations Interrupted Cutting Heavy Light Coated carbide cermet SUMIBORO Cutting Speed (m/min) 3 2 Continuous Cutting Ceramic Hardness of Work Material (HRC) Carburised or Induction Hardened Material Bearing Steel Die Steel Prone to notch wear Wear fairly large Wear large Influence of Coolant on Tool Life Continuous Cutting Flank Wear Width VB (mm) DRY Oil-base coolant Water soluble emulsion Water soluble 2 In continuous cutting of bearing steel, there is not much difference in dry or wet cut Cutting Time (min) Work: SUJ2(58 to 62HRC) Condition: TPG634 vc=m/min ap=.5mm f =.mm/rev Continuous cutting Interrupted Cutting SKD 4U Slotting Cutting speed vc=m/min D.O.C ap=.2mm Feed rate f =.mm/rev Tool Life 5 Heavy DRY Interrupted Cutting Wet For continuous cutting, the influence of coolant on tool life is minimal. However, for interrupted cutting, coolant will shorten the tool life because of thermal cracking. Relation Between Work Material Hardness and Cutting Force Cutting Force () 5 5 Principal force Feed force Back force Hardness of Work Material (HRC) Back force increases substantially for harder work materials. Principal force Feed force Back force Work : SK 3 Conditions : C/speed vc=2m/min. D.O.C ap=.2mm Feed rate f =.mm/rev Relation Between Flank Wear and Cutting Force Influence of Work Material Hardness on Cutting Force and Accuracy Back Force () Principal Force () Feed Force () 3 2 SCM43 65HRC S55C 24HRC.5. Flank Wear Width VB (mm) Condition: C/speed vc=8m/min D.O.C ap=.5mm Feed rate f =.mm/rev For hardened steel machining, back force increases substantially due to the expansion of flank wear. Shore Hardness (HS) Back Force () Dimension (m) Hard zone Soft zone Work: S38C Hard zone 45(HS) 6 3μm Cutting Speed : vc=2m/min Depth of Cut : ap=.5mm Feed rate : f =.3mm/rev Dry External dimension at the soft zone is smaller due to lower cutting forces. Relation Between Cutting Speed and Surface Roughness Surface Roughness Ra (m).3.2. B25 V=2 B25 V=5 B25 V=8 Work: SCM42H 58 to 62HRC Holder: MTXR2525 Insert: U TMA648 Conditions: vc= 2, 5, 8 m/min f =.45mm/rev ap=.5mm Wet Improvement of Surface Roughness by Altering the Feed Rate Constant Feed Rate Variable Feed Rate Previous edge position Stationary otch Location Shifting otch Location Machining Output (pcs.) At high cutting speeds, surface roughness is more stable. Varying the feed rate spreads the notch location over a larger area. Surface finish improves and notch wear decreases. 27

20 Technical Guidance High Speed Machining of Cast Iron withs SUMIBORO SUMIBORO Edition Advantages of Using SUMIBORO for Cast Iron Machining Higher Accuracy Longer Tool Life at Higher Cutting Speeds Grey Cast Iron Ductile Cast Iron Size Accuracy Good BS8 B7 BC5 Ceramic Coated Carbide Cermet Good Surface Roughness Ra (m) Cutting Speed (m/min), 5 2 Ceramic Coated Carbide Cermet BS8 B7 B5 2 Tool Life Ratio Cutting Speed (m/min) 5 2 Ceramic Coated Carbide Cermet Tool Life Ratio BX BC5 B7 Turning Cast Iron Structure and Wear Shape Examples FC FCD Structure Matrix Pearlite Pearlite + Ferrite Flank Wear Width VB (mm) Dry Wet (Water soluble) Cutting Length (km) Work : FC25 Continuous cutting Tool material : B5 Tool Shape : SG248 Conditions : vc=45m/min ap=.25mm f =.5mm/rev Dry&Wet (water soluble) Surface Roughness Rmax (m) Cutting Speed vc (m/min) Tool Wear Shape Wet Dry Crater wear (v c = 2 to 5m/min) Wet (Water soluble) Dry For machining cast iron with SUMIBORO, cutting speeds (vc) should be 2m/min and above. WET cutting is recommended. Machine : /C lathe Work : FC25 2HB Holder : MTJP2525 Tool material : B5 Tool Shape : TMA648 Conditions : vc= to 28m/min f =.mm/rev ap=.mm Wet Milling SUMIBORO B Finish Mill EASY High speed machining v c =2,m/min Surface Roughness 3.2Rz (.Ra) Running cost is reduced because of economical insert. Easy insert setting with the aid of a setting gauge. Employs safe, anti-centrifugal force construction for high-speed conditions. Flank Wear width (mm) Ceramic vc=4m/min Ceramic vc=6m/min vc=6m/min vc=,m/min vc=,5m/min umber of Passes (Pass) umber of Passes (Pass) Cutting Conditions p=.5mmz=.5mm/ Dry Wet Thermal cracks occur ,5,2,35,5 Cutting Speed (m/min) (Conditions) Work: FC25Condition: ap =.5mm fz =.mm/t Dry Tool material: B7 Dry cutting is recommended for high speed milling of cast iron with SUMIBORO. 28

21 SUMIBORO Edition Technical Guidance Machining Hard-to-cut Materials with SUMIBORO Powder Metal SUMIBORO Carbide Cermet Flank Wear Width (mm). Flank Wear 2. Surface Roughness 3. Height of Burr Cutting Speed (m/min) Cutting Speed (m/min) Cutting Speed (m/min) Work: SMF44 equivalent, Process details: ø8-ømm heavy interrupted facing with grooves and drilled holes. (After 4 passes) Cutting Conditions: f=.mm/rev, ap=.mm, Wet Insert: TGA644 Surface Roughness Rz (m) For general powder metal components, carbide and cermet grades can perform up to vc=m/min. However, around vc=2m/min SUMIBORO, on the other hand, exhibits stability and superior wear resistance, burr prevention and surface roughness especially at high speeds. Max Height of Burr (mm) Heat Resistive Alloy i Based Alloy Typical tool damage of CB tool when cutting Inconel 78 Influences of cutting speed (Grade BX2, f =.6mm/rev, L=.72km) vc =3m/min vc =5m/min otch wear Flank Wear Flank Wear Influences of feed rate (Grade BX2, vc=3m/min, L=.8km) f otch wear f Flank Wear Influence of tool grade (vc=5m/min, f =.2 mm/rev. L=.36km) BX2 B7 otch wear Flank Wear Conditions: ap=.3mm, Wet Cutting Speed (m/min) Conditions: f=.6mm/rev, ap=.3mm, Wet B7 BX2 Whisker Reinforced Ceramic Cutting Length (m) Tool life criteria otch wear =.25mm () Or flank wear =.25mm BX2 is recommended for high speed and low feed rates B7 is recommended for cutting speeds below vc=24m/min. Cutting Speed (m/min) Conditions: f=.2mm/rev, ap=.3mm, Wet B7 BX2 Whisker Reinforced Ceramic Coated carbide (K series) 2 3 Cutting Length (m) Tool life criteria otch wear =.25mm () Or flank wear =.25mm B7 is recommended for cutting at high feed rates. (Over f =.mm/rev) Ti Based Alloy Flank Wear Width V (mm).2 B7 Breakage Work: Ti 6A 4V Insert: F DMX244 Cutting Conditions: vc =m/min ap =.mm f =.5mm/rev Wet SUMIDIA positive type inserts are extremely good for Ti Alloy, due to high cutting edge strength and high wear resistance. Hard Facing Alloys Work: Colmonoy o.6 (icr-based self-fluxing alloy) DA5 5 5 Cutting Time (min.) K Flank Wear Width V (mm).2 B7 Breakage Cutting Time (min.) Work: Ti 6A 4V Insert: F DMX244 Cutting Conditions: vc =m/min ap =.mm f =.5mm/rev Wet SUMIDIA positive type inserts are extremely good for Ti alloy, due to high cutting edge strength and high wear resistance. DA5 K Work: Stellite SF-2 (Co-based self-fluxing alloy) Flank Wear Width V (mm).2 DA5 Breakage.5..5 B Cutting Time (min.) Work: Ti 6AI 4V Tool: DMA542 Cutting Conditions: vc =2m/min ap =.3mm f =.25mm/rev Wet egative type insert in high fracture resistant B7, is suitable for high-efficiency machining with large depth-of-cut and high feed rates. Insert : SG 938 Cutting Conditions : vc = 5,3m/min f =.mm/rev ap =.2mm Dry Flank Wear Width (mm) BS8 ( c =3m/min) Whisker reinforced ceramic ( c =5m/min) Cutting is difficult because of large wear at c =5m/min. Small wear at c =3m/min Cutting Length (km) Whisker Reinforced Ceramic (vc =5m/min, After.km of cutting) BS8 (vc =3m/min, After km of cutting) Insert : SG938 Cutting Conditions : vc = 5m/min f =.mm/rev ap =.2mm Dry Flank Wear Width (mm) Chipping BS8 Comp. s solid CB o chipping Cutting Length (km) Chipping Comp.'s solid CB After 2km of cutting BS8 After 2km of cutting 29

22 Technical Guidance Tool Failure and Remedies SUMIBORO Edition Type of Insert Failure Cause Countermeasures Flank Wear Grade lacks wear resistance. Cutting speed is too fast. Select a more wear resistant grade. BC2,B,B2 Decrease the cutting speed. Reduce the cutting speed to less than v c=2m/min. (Higher feed rate reduces the overall tool-to-work contact time.) Use an insert with a larger relief angle. Crater wear Breakage At Bottom of Crater Grade lacks wear resistance. Cutting speed is too fast. Change to a high efficiency grade. BC2,BX25,BX2 Reduce cutting speed and increase feed rate (low-speed, high-feed cutting). Reduce the cutting speed to less than v c=2m/min. (Higher feed rate reduces the overall tool-to-work contact time.) Flaking Grade lacks toughness. Back force is too high. Select a tougher grade (e.g. BC22 and B2). Select an insert with a stronger cutting edge (Increase negative land angle and edge honing) If the grade has enough toughness, improve the cutting edge sharpness. otch Wear High boundary stress. Change to a grade with a higher boundary wear resistance (e.g. BC2 and B2). Increase the cutting speed (5m/min or more). Change to "Variable Feed Rate" method, which alters the feed rate at every fixed number of outputs. Increase negative land angle and edge honing. Chipping at Forward otch Position Impact to front cutting edge is too large or there is constant occurrence. Change to a fine-grained grade with a higher fracture resistance (e.g. BC3 and B35). Increase feed rates (Higher feed rates are recommended to reduce chipping.) Select an insert with a stronger cutting edge (Increase negative land angle and edge honing) Chipping at Side otch Position Impact to side cutting edge is too large or there is constant occurrence. Select a tougher grade.b35,bc3 Reduce feed rate. Increase the side cutting angle Increase insert nose radius Select an insert with a stronger cutting edge (Increase negative land angle and edge honing) Thermal Crack Thermal shock is too severe. Completely dry condition is recommended. Select a grade with better thermal conductivity. Decrease cutting speed, depth of cut, feed rate. 3