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.

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 Forging die & flash Source geometry and die and flash size. Forging die OX flash

9. © 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

10. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Continuous Cross Section Rolling Extrusion Drawing

11. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Rolling ( 압연 ) Metal stock is passed through a pair of rolls to reduce thickness. Hot rolling ( 열간압연 ) > recrystallization temperature > Cold rolling ( 냉간압연 ) (Roll bending) (Roll forming) Flat rolling Ring rolling Structural shape rolling http://www.youtube.com/watch?v=6xnKmt_gsLs&p=9B6D9EAE75875D9Dhttp://www.youtube.com/watch?v=6xnKmt_gsLs&p=9B6D9EAE75875D9D Rolling 3m

12. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Flat Rolling ( 평판 압연 ) Rectangular cross-section (sheet, plate) Force: F ≈ σ y lw Draft: t 0 - t f < μ 2 R t0t0 tftf R w l F

13. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Ex) Flat Rolling Force Power Ductile plate (width: 0.1 m, thickness: 10 mm, strength: 400 MPa) is rolled by flat rollers (radius: 0.1 m). The friction coefficient of roller and plate is 0.2 and production rate is 1 m/s. How many times should the plate pass the roller to get 5 mm thickness plate? Please predict approximate rolling Force (kN) and Power (kW).

14. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Ring rolling ( 링압연 ) Driven and idle roll presses the ring to decrease thickness and increase diameter. Driven roll Idler roll Side roll http://www.youtube.com/watch?v=GDyWyDP3cvshttp://www.youtube.com/watch?v=GDyWyDP3cvs Ring rolling

15. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Structural shape rolling ( 형압연 ) Structural shape rolling uses profile rolling techniques where the workpiece is passed through a series of rollers that match the workpieces' cross-section.

16. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Thread rolling ( 나사 전조 ) Bolt: http://www.youtube.com/watch?v=7ORomNNCSUQ&p=9B6D9EAE75875D9D Bolt Nut 5mhttp://www.youtube.com/watch?v=7ORomNNCSUQ&p=9B6D9EAE75875D9D www.horstengineering.com Threads are formed by pressing a blank with the former(shaped die). Thread Rolling Die Blank

17. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Extrusion ( 압출 ) Hot extrusion profiles of steel A round billet is placed in a chamber and forced through a die opening by a ram. It creates complex fixed cross-sectionals. Pressure: p≈σ y (0.8+1.4ln(A o /A f )) Die Ram F Billet Container http://www.youtube.com/watch?v=7qiDJ5U4uRchttp://www.youtube.com/watch?v=7qiDJ5U4uRc Extrusion 1m AfAf AoAo

18. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Drawing ( 인발 ) Reduce the cross-section of a road, wire or tube by pulling it through a drawing die Lubrication is essential for good surface finish and long die life Die A0A0 AfAf F

19. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Spring forming machine Spring forming machine controlled by mechanical cam and link. http://ma.gnu.ac.kr/vod/Forming/Spring_Former.wmvhttp://ma.gnu.ac.kr/vod/Forming/Spring_Former.wmv Spring former

20. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Rotary Swaging Split dies separate and close to reduce the diameter and produce a taper of tube. Tube Die Mandrel

21. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Tube (Pipe) Bending Straight tube is bended into the desired form. Be careful to buckle inward during bending. http://ma.gnu.ac.kr/vod/forming/Pipe_Bending.wmv Former Clamp Tube bending

22. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Tube Hydroforming SME: http://www.youtube.com/watch?v=nylIvins3XE http://www.youtube.com/watch?v=nylIvins3XE Com: http://www.youtube.com/watch?v=i2ac6A3FJ6E&hl=kohttp://www.youtube.com/watch?v=i2ac6A3FJ6E&hl=ko Hydraulic pump injects high pressure fluid inside a hollow tube to expand until it matches a negative mold. Strong and light structures for vehicles Dies Seals Hydraulic pressure Tube

23. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Characteristics ( 특징 ) AdvantagesDisadvantages Fast & mass productionExpensive equipment and dies Improved strengthDuctile materials Surface finish and tolerance are better than casting Shape is limited by strain/flow Size is limited by force/equipment Strength is improved because of work hardening, grain refining, fevering, defect closure Surface finish and tolerance are better than casting, worse than machining

24. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Economics ( 경제성 ) Tool and die cost middle or high but spread over the number of parts For large quantities forging is more economical than sand casting 10 0 10 1 10 2 10 3 10 4 10 5 10 6 Number of pieces Cost per pieces 1 2 3 4 5 6 7 8 9 Sand casting Investment casting Die casting Forging

25. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes Bulk Deforming Simulation http://www.afdex.com

26. © 2012 Su-Jin Kim GNU Bulk Deforming Manufacturing Processes References http://www.afdex.com http://www.kforge.or.kr http://www.posco.co.kr