Drilling, boring reaming operation on lathe
- 1. DRILLING|Boring|Reaming Machine Tools & Machining Department of Mechanical Engineering University of Engineering & Technology Lahore
- 2. Presented By: Ali Raza 2017-ME-516
- 3. Drilling • Drilling is a material removing or cutting process that uses a drill bit to cut a hole of circular cross- section in solid materials • The bit is pressed against the work-piece and rotated at rates from hundreds to thousands of revolutions per minute.
- 4. Working Principle • The rotating edge of the drill exerts a large force on the workpiece and the hole is generated. • The removal of metal in a drilling operation is by shearing and extrusion.
- 5. Materials High Speed Steel (HSS) is used to drill metal Cobalt Steel alloys are used to drill stainless steel and other hard material Low carbon steel is used for drilling wood Tungsten carbide is used to drill hole with diameters less than 1 mm Polycrystalline diamond (PCD) bits are typically used in the automotive, aerospace, and other industries to drill abrasive aluminum alloys, carbon-fiber reinforced plastics, and other abrasive materials
- 6. Materials Coating Black Oxide Titanium nitride Titanium Aluminium Nitride Titanium Carbon Nitride Zirconium Nitride Aluminium Chromium Silicon Nitride Boron Aluminium Magnesium
- 7. 1- Operations | Drilling When we need a circular hole in a workpiece of any size there, we can use drilling operation, by a drilling operation we can form any size of holes in a workpiece.
- 8. 1- Drilling: Centre Drill If a long piece of material has to be turned on a lathe then a centre drill is used to produce the hole at one end. This allows the drilled end to be supported by the tailstock centre. The starting point for drilling with a centre lathe is to use a countersink bit. This is used to drill slightly into the material and creates a starting point for other drills that are going to be used
- 9. 1- Drilling: Twist Drill Once a hole has been produced by a centre drill, machine twist drills can be used to enlarge the hole and if necessary to drill all the way through.
- 10. 2- Operations | Boring Boring operation is used to enlarge a hole or cylindrical cavity made by a previous process (drilling) or to produce circular internal grooves. Boring process can be done after drilling operation.
- 11. 3- Operations | Reaming Reaming process is used to finishing the drilled hole. Reaming process makes the surface smooth.
- 12. Troubleshoot Possible Errors: 1. Insufficient Machine Torque 2. Insufficient Machine Power 3. Hole not symmetrical 4. Poor Toll Life 5. Broken insert screw 6. Deflections 7. Hole not cylindrical 8. Flank or Crate wear 9. Drill Breakage
- 13. Troubleshoot 1- Indexable Insert Drill: Increase coolant flow, clean filter, clear coolant holes in drill Check alignment on lathe
- 14. Troubleshoot 2- Vibrations: • Shorten drill overhang, improve the workpiece stability • Reduce cutting speed
- 15. Troubleshoot 3- Chip jamming in the drill flutes: • Check geometry and cutting data recommendations • Increase coolant flow, clean filter, clear coolant holes in drill • Reduce feed within recommended cutting data • Increase cutting speed within recommended cutting data