표제지
목차
요약문 7
Abstract 8
제1장 서론 10
제2장 본론 14
2.1. 2행정 디젤엔진에서의 배기밸브 스핀들 개요 14
2.2. 2행정 디젤엔진에서의 배기밸브 스핀들 관련 개발 동향 16
2.3. 엔진제조사의 배기밸브 스핀들 설계 및 기준 19
2.4. 엔진제조사의 듀라스핀들 재생 수리 절차 23
2.5. 용접 재질에 대한 요건 24
2.6. 용접절차서의 유효성 26
2.7. 용접공의 인증 27
제3장 듀라스핀들의 재생 수리 28
3.1. 재생 수리 전 최초 검사 및 용접 전 기계가공(machining) 28
3.2. 용접 31
3.2.1. SMAW 34
3.2.2. GTAW 34
3.2.3. GMAW/GMAW-P 35
3.3. 압연(rolling) 42
3.4. 열처리 47
3.5. 최종 가공 및 검사 49
제4장 결론 54
참고문헌 55
Table 2.1. DuraSpindle and Nimonic spindle 15
Table 2.2. Required mechanical properties for SNCrW 19
Table 2.3. Required hardness for SNCrW 20
Table 2.4. Required chemical composition for SNCrW 20
Table 2.5. Heat treatment for SNCrW 20
Table 2.6. Required physical properties for SNCrW 21
Table 2.7. Previous spindle lifetimes 21
Table 2.8. Maximum burn-away and allowable burn-away rates 22
Table 2.9. Updated spindle lifetime 22
Table 2.10. Welding requirements for spindle materials 24
Table 3.1. Requirements of welding consumables 33
Table 3.2. Welding parameters for Inconel 625 & Inconel 718 35
Table 3.3. Requirements for welding consumables 36
Table 3.4. Filler metal sample analysis 37
Table 3.5. Rolling parameters 45
Table 3.6. Heat treatment cycle for Inconel 718 47
Fig. 1.1. FBIV principles 10
Fig. 1.2. TCEV details 11
Fig. 1.3. Traditional ME engine exhaust concept(left)... 11
Fig. 2.1. History of exhaust valve spindle 14
Fig. 2.2. Photo of exhaust valve spindles 15
Fig. 2.3. HIP sheet metal capsule production 18
Fig. 2.4. Rolling process of DuraSpindle 19
Fig. 2.5. DuraSpindle reconditioning procedure 23
Fig. 2.6. Hardening depth 25
Fig. 3.1. Incoming base material and... 28
Fig. 3.2. Requirement of the height of... 29
Fig. 3.3. Welding positions 31
Fig. 3.4. Welding specifications on base metal 32
Fig. 3.5. GMAW, bottom & side with Inconel 625 38
Fig. 3.6. GMAW, Seating surface with... 38
Fig. 3.7. Non-destructive test(PT,UT) after welding (Inconel 625) 39
Fig. 3.8. Machining - The welding groove is machined 40
Fig. 3.9. PT & UT prior to rolling 41
Fig. 3.10. Position of rolling tool 43
Fig. 3.11. Requirements of rolling on... 43
Fig. 3.12. A section of the rolled seat area 44
Fig. 3.13. Definition of rolling diameter and rolling depth 45
Fig. 3.14. Non-destructive PT test after rolling 46
Fig. 3.15. Heat treatment cycle 48
Fig. 3.16. Heat treated exhaust valve spindle 48
Fig. 3.17. Non-destructive test after final machining 49
Fig. 3.18. Positions on base metal for hardness test 50
Fig. 3.19. The half-spindle disc for the... 51
Fig. 3.20. Penetration test for half-spindle... 51
Fig. 3.21. Cracks and microstructure investigation at the interface 52