tailieunhanh - mechanical design an integrated approach Part 7

Tham khảo tài liệu 'mechanical design an integrated approach part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 340 PART ì Fundamentals Given Sil 150 ksi s 72 ksi Design Decision Employ the Goodman criterion based on the maximum normal stress. in. Figure A cantilever spring is subjected to a concentrated load p varying continuously from 0 to P Figure . What is the greatest allowable load po for n 4 Given Sy 850 MPa Se 175 MPa b 5 mm h 10 mm Kf 2 Assumption Failure occurs due to bending stress at the fillet. Design Decision Use the Soderberg criterion. 200 mm Figure Resolve Problem for the load varying from Po 2 upward to po downward n 2. A 24-mm wide 4-mm thick and 3-mm long leaf spring made of AISĨ 1050CD steel is straight and unstressed when the cam and shaft are removed Figure . Use the Goodman theory to calculate the factor of safety n for the spring. Given se 250 MPa E 200 GPa V Assumption The cam rotates continuously. Leaf spring is considered as a wide cantilever beam. ị 4 mm 20 mm 300 mm 10 mm Figure Repeat Problem for the case in which the cantilevered spring is made of normalized AĨSĨ 1095 steel and employing the Soderberg criterion. Figure shows a circular aluminum bar having two shoulder fillets supporting a concentrated load p at its midspan. Determine the allowable value for diameter D if stress conditions at the fillets are to be satisfactory for conditions of operation. Dimensions shown are in millimeters. CHAPTER 8 Fatigue 341 Given su 600 MPa 5y 280 MPa n KfSe 150 MPa Assumptions The load p varies from 2 kN to 6 kN. The Soderberg relation is employed. P 60 diameter . I f 9 60 diameter zfe iZ I I k 500 300 4 300 - 500 I Figure The filleted flat bar shown in Figure is made from 1040 Steel OQ T at 650 c. What is the factor of safety n if the bending moment M varies from to 3 kN m Given KfSe 400 MPa D 120 mm d 60 mm r 4 mm t 20 mm Design Assumption The Goodman criterion of fatigue failure is applied. Figure í Applications is iiilM Hill Hill UiH1 1 .