1. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU Turning ( 선삭 ) A piece of material is rotated and a single point cutting tool is traversed along 2 axes of motion to produce the cylinder, tubular components and various rotational geometries.

2. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU Lathe ( 선반 ) Turning can be done manually, in a traditional form of lathe, which frequently requires continuous supervision by the operator.

3. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU 1 st Korean Lathe

4. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU CNC Lathe, Turning center Turning can be done by using a computer numerical control, known as CNC.

5. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU Turning center Turning center has additional milling axis is called TurmMill ( 복합기 ) http://ma.gnu.ac.kr/vod/machining/TurnMill.AVI

6. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU http://www.youtube.com/watch?v=tDc0l9Gm8D4 Turning process ( 선삭공정 ) Straight turning Taper turning Profiling (Couture turning) External grooving http://www.youtube.com/watch?v=5AB_etoHesI&p=9B6D9EAE75875D9D

7. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU Math for Turning Cutting speed(mm/min) = 3.14 x Diameter x Spindle V = π D S MRR (Material Removal Rate) = Volume / Time = 3.14 x Diameter x Depth x Feed per revolution x Spindle Cutting time = Distance / (Feed per revolution x Spindle) V S S

8. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU A 15.24-cm-long, 1.27-cm-diameter 304 stainless-steel rod is being reduced in diameter to 1.2192 cm by turning on a lathe. The spindle rotates at N=4000 rpm and the tool is travelling at an axial speed of 20.32 cm/min. Calculate the cutting speed, material-removal rate, cutting time, power dissipated, and cutting force. Solution Maximum cutting speed is Cutting speed at machined diameter is Depth of cut and feed is Ex) Turning

9. Machining Manufacturing Processes © 2012 Su-Jin Kim GNU Solution Material-removal rate is Actual time taken to cut is Amount of power dissipated is The torque and cutting force is Ex) Turning