1. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Bulk Deforming ( 부피 성형가공 ) © © www.afdex.com Su-Jin Kim Mechanical Engineering Gyeongsiang National University Korea

2. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Contents Forging Rolling Extrusion Drawing Tube deforming

3. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Forging ( 단조 ) Forging is the shaping of metal using plastic deformation takes place by compressive forces. It can be carried out at room (cold forging 냉간단조 ) or above recrystallization temperature (hot forging 열간단조 ). Stronger than an equivalent cast or machined part. Expensive die, press and furnace facilities. Post machining is required. Ductile metal. http://www.youtube.com/watch?v=PXVWiGqeltMhttp://www.youtube.com/watch?v=PXVWiGqeltM Forging 5min

4. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Open-die forging( 자유단조 ) Open-die forging is usually done by hammering a part between two flat faces. It is used to make parts that are too big to be formed in a closed die or in cases where only a few parts are to be made without die. http://www.youtube.com/watch?v=tLRkOupbARM&p=9B6D9EAE75875D9Dhttp://www.youtube.com/watch?v=tLRkOupbARM&p=9B6D9EAE75875D9D SME 1min ©steelindustriesinc.com

5. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Open-die forging Berreling is caused by friction force at die-workpiece interface. Friction and the aspect ratio effects forging force. Forging force: F≈σ y A(1+μr/h) Barreling F μ, friction Die h r

6. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Impression-die forging ( 형단조 ) Workpiece acquires the shape of the die cavity while deformed between the closing dies. Forging force : also called Closed-die forging ( 패쇠단조 ) Die Flash Land Parting line k p : pressure-multiplying factors (3~12)

7. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Forging Die ( 단조 금형 ) Require multi-stage forging to ensure proper distribution of the material in the die cavities. Parting line is designed based on shape, metal flow, force. Flash clearance is 3% of max thickness. Draft angle > 5~7° for steel. Corner fillets radii for smooth flow. low and wide Ribs Metal fiber flow lines. Die Parting line Draft angle Rib Flow lines Fillet Flash

8. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Impression-die hot forging 1STAGE2STAGE 3STAGE ©gsf.co.kr Bucket Tooth http://ma.gnu.ac.kr/vod/Forming/Hot_Forging.wmvhttp://ma.gnu.ac.kr/vod/Forming/Hot_Forging.wmv Hot forging