Pankaj 161616

of 22/22
Department of Mechanical Engineering 1 Pre-Project Presentation Measurement of Residual Stress Distribution & Fatigue Life Assessment of Butt Welded Joint Pankaj Kumar : (1BG11ME034) Shailendra Kumar : (1BG11ME048) Dinesh Sah : (1BG11ME014) Shree Kaustub : (1BG11ME053) Internal Guides: Mr .Vasudev.U Mr. Harish Mr.Karthik Asst. Prof. Asst. Prof. Asst. Prof. Mechanical Dept. Mechanical Dept. Mechanical Dept. B.N.M.I.T B.N.M.I.T B.N.M.I.T
  • date post

    07-Aug-2015
  • Category

    Documents

  • view

    121
  • download

    2

Embed Size (px)

Transcript of Pankaj 161616

  1. 1. Department of Mechanical Engineering 1 Pre-Project Presentation Measurement of Residual Stress Distribution & Fatigue Life Assessment of Butt Welded Joint Pankaj Kumar : (1BG11ME034) Shailendra Kumar :(1BG11ME048) Dinesh Sah :(1BG11ME014) Shree Kaustub :(1BG11ME053) Internal Guides: Mr .Vasudev.U Mr. Harish Mr.Karthik Asst. Prof. Asst. Prof. Asst. Prof. Mechanical Dept. Mechanical Dept. Mechanical Dept. B.N.M.I.T B.N.M.I.T B.N.M.I.T
  2. 2. Department of Mechanical Engineering 2 Aim of the Project Measurement of Residual Stress Distribution and Estimation of Fatigue life of a Butt Welded Joint before and after surface treatment.
  3. 3. Department of Mechanical Engineering 3 Project Objectives 1] To review the literature on fatigue life of welded joint and on surface enhancement treatment. 2] Experimental investigation of induced residual stress in butt welded joint before and after surface modification process by shot peening method. 3] Estimation of fatigue life in butt welded joint before and after surface modification process. 4] Analyzing the Effect of residual stress modification on fatigue life of the welded component.
  4. 4. Department of Mechanical Engineering 4 Methods and Methodology Objective 1: To review the literature on fatigue life of welded joint and on surface enhancement treatment. Literature Review: Sylvain Chataingner et al: Steel structures are mainly prone to two types of degradation: corrosion and fatigue particularly in the case of welded structures. The presented work aims at investigating two treatment methods to increase the fatigue life expectancy of welded steel joints. It includes both numerical and experimental investigations and is interested in the use of shot peening. As far as experimental investigations are concerned, for both treatment methods and for untreated samples, the stress concentration coefficients are determined, surface residual stresses are measured using X-ray diffraction and fatigue tests are conducted. The results allow explaining for both methods the observed improvements in fatigue behaviour.Numerical investigations are concerned and this allows the determination of residual stresses due to welding operation and their comparison with the former experimental measures.
  5. 5. Department of Mechanical Engineering M Hasegawa et al: The shot peening method, which requires simple equipment and treatment, is extensively employed as a method to improve fatigue strength. However, conventional steel ball shot material has a low specific gravity, so high speed projection is required in order to improve fatigue strength; thus, the accompanying noise and high air flow are problems. Accordingly, in order to improve these aspects, high hardness and high specific gravity shot material has been developed with 1.7 times the hardness (HV1400) and approximately 1.9 times the specific gravity (approximately 14) compared with a conventional steel ball. Mark S. Molzen et al: The welding process induces residual tensile stress that is detrimental to fatigue life. Tensile stresses act to stretch or pull apart the surface of the material. With enough load cycles at a high enough tensile stress, a metal surface will initiate a crack. Significant improvements in fatigue life can be obtained by modifying the residual stress levels in the material. Two methods of performing this are through heat treating and shot peening. Both will be thoroughly analyzed in this paper through the use of x-ray diffraction. X-ray diffraction is the most accurate and best-developed method to characterize the residual stress in polycrystalline material. Methods and Methodology
  6. 6. Department of Mechanical Engineering Manoj Saini et al: Dissimilar metal joints between austenitic stainless steels and carbon steels containing low amounts of carbon are being extensively utilized in many high-temperature applications in energy conversion systems. In steam generating power stations, the parts of boilers that are subjected to lower temperatures as in the primary boiler tubes and heat exchangers are made of ferritic steel(mild steel) for economic reasons. Other parts, such as the final stages of the super heaters and repeaters operating at higher temperatures where increased creep strength and resistance to oxidation are required, are constructed with austenitic stainless steels. Therefore, transition welds are needed between the two classes of materials.Dissimilar metal weld is also used to anlysis of strength of joint.Beacause due to residual stress induces in the weld.We can find the amount of residual stress in two different metal. Methods and Methodology
  7. 7. Department of Mechanical Engineering Literature Summary : Residual stresses are a consequence of the welding process and are an important consideration in structural assessment . The welding process induces residual tensile stress that is detrimental to fatigue life. Tensile stress act to stretch or pull apart the surface of the material . With the enough load cycles at a high enough tensile stress a metal surface will initiate the crack . It is commonly observed that complex fabricated structures subject to fatigue loading fail at the welded connections. Some problems can be corrected by improved detail design but fatigue performance can also be improved using post-weld improvement methods. Methods and Methodology
  8. 8. Department of Mechanical Engineering 8 Method and Methodology RESIDUAL STRESS MODIFICATION: Residual stress can significantly affect engineering properties of materials and structural components, notably fatigue life, distortion, dimensional stability, corrosion resistance etc. The residual stress analysis is a compulsory stage in the design of structural elements and in the estimation of their reliability under real service conditions Significant improvement in the fatigue life can be obtained by modifying the residual stress levels in the material. Some of the different methods of residual stress modification methods are a.) Shot peening b.) Hammer peening c.)Ultrasonic method d.) Heat treatment.
  9. 9. Department of Mechanical Engineering Shot peening: Shot peening is a cold work process used to finish metal parts to prevent fatigue and stress corrosion failures and increase product life for the part. In shot peening, small spherical shot bombards the surface of the part to be finished. The shot acts like a peen hammer, dimpling the surface and causing compression stresses under the dimple. Methods and Methodology
  10. 10. Department of Mechanical Engineering Objective 2: Experimental investigation of induced residual stress in butt welded joint before and after surface modification process. Experimental details : a. Material: Stainless steel 304L and Mild steel. b. Specification of material: 25125 (all dimension in mm). c. Type of joint : Butt welded joint. d. NDE technique for residual stress measurement. Methods and Methodology
  11. 11. Department of Mechanical Engineering Methods and Methodology X-Ray Diffraction Method:
  12. 12. Department of Mechanical Engineering Methods and Methodology XRD is a non destructive method which is used to measure stress in the material without damaging it. XRD uses x-ray beam which is made to incident on the material surface for which we need to find stress. XRD uses Braggs law to determine the stress on the surface of material.
  13. 13. Department of Mechanical Engineering Objective 3: Estimation of fatigue life in butt welded joint before and after surface modification process. Estimation of fatigue life of the butt welded component is carried out with the help of MTS uni axial testing machine. Specimen prepared for fatigue Testing Methods and Methodology
  14. 14. Department of Mechanical Engineering Objective 4: Analyzing the Effect of residual stress modification on fatigue life of the welded component. Stress modification process such as Shot peening reduces the residual tensile stress and induces the residual compressive stress in the specimen. Due to Shot peening the fatigue life and hardness of the component increases. Methods and Methodology
  15. 15. Department of Mechanical Engineering Work Done Till Now After completing literature survey the ASTM standard specimen specification is prepared. Selection of material(MS,SS 304L). Purchase of material Welding Shot peening Measurement of Residual stress Type of material C Mn P S Si Cr Ni N I Mild Steel 0.16- 0.18% 0.7- 0.9% 0.04 max 0.04 max 0.40 max - - - - Stainless Steel (304L) 0.03 max 2 max 0.045 max 0.030 max 0.75 max 18-20% 8-12% 0.1 max Balance
  16. 16. Department of Mechanical Engineering Remaining Work Fatigue Test Hardness test
  17. 17. Department of Mechanical Engineering 17 Project Schedule Total duration of project is 16 weeks Activity/ Week W-0 W-1 2/3/15 to 8/3/15 W-2 9/3/15 to 15/3/15 W-3 16/3/15 to 22/3/15 W-4 23/3/15 to 29/3/15 W-5 30/4/15 to 5/4/15 W-6 20/4/15 to 25/4/15 W-7 25/4/15 to 2/5/15 Pre-Project Presentation 1st Presentation Literature Survey Selection of material Purchase and Machining of Material Butt Welding Residual stress measurement Shot peening Residual stress measurement Fatigue Test Result and verification Final Presentation Submission of Technical Paper, Poster, Final Report
  18. 18. Department of Mechanical Engineering Place of Work B.N.M. Institute of Technology C.M.T.I, Bangalore Hi-Tech Enterprises, Pune Acharya Institute of Technology, Bangalore
  19. 19. Department of Mechanical Engineering 19 Resources Software Resources: 1] Solid edge 2] FEM software, ANSYS-15(advanced)
  20. 20. Department of Mechanical Engineering 20 References 1] R. Snoeys, Thermal Damage in Grinding, Proc. Milton C. Shaw Grinding Symp., R. Komanduri and D.Maas, Ed. (Miami Beach, FL), The American Society of Mechanical Engineers, 1985, p 425-434 2] J. Peters, R. Snoeys, and M. Maris, Residual Stress in Grinding, Advanced Fabrication Processes, Conference Proceedings No. 256, Advisory Group for Aerospace Research and Development. 3] J.S. Eckersley and T.J. Meister, Intelligent Design Takes Advantage of Residual Stresses, Practical Applications of Residual Stress Technology, Clayton Ruud, Ed., ASM International, 1991, p 175-181 4] Control of Residual stresses, Material Selection and Design, ASM Hand Book, 20, ASM International , USA 5] Haagensen, P. J., Alnes O., 2005. Progress report on IIW WG2 round robin fatigue testing program on 700 MPa and 350 MPa YS steels. International Institute of Welding Doc. XIII-2081-05. 6] Hobbacher, A., 2009. IIW Recommendations for Fatigue Design of Welded Joints and Components. WRC Bulletin 520, Welding Research Council, New York, pp. 144
  21. 21. Department of Mechanical Engineering 21 Benefits of the work Will it result into a publication? yes Will it result into a product? yes Will it be a solution to an existing problem of an industry? yes Is it pursued for academic interest? Yes
  22. 22. Department of Mechanical Engineering 22 Thank You