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 Posted by: Linksys20 ® 01/26/2005, 14:52:14 Author Profile eMail author Edit Hello EveryoneI'm a baby to Design Engineering and really cant find the answers to the below questions, any help would be brilliant. 1) Two parallel shafts, carrying 0.6 m diameter and 0.5 diameter are 3 m apart and are connected by a belt so arranged that the shafts rotate in opposites directions. If the drive is to be altered so that the shafts will rotate in the same direction, by how much should the belts be short end?2) Find the diameter and length of a mild steel end journal on which there is a load of 35 KN (shock loading). Assume a safe working stress of 40 MPa and a lengh:diameter ratio of 1.5 3) A load of 6400 Kg is carried by a journal rotating in a 270 mm bearing diameter and 400 mm long. Find the specific load on the bearing and the heat generated per minute in the bearing, assuming the shaft speed is 4 r/s and the coefficient of friction is 0.018. 4) A V Belt pulley drive is required to transmit 1.5 Kw power. Assuming a coefficient of friction of 0.3 between pulleys and belt, and a maximum belt tension of 15KPa of width, find the necessary width of belt. The angle of Vee is 30 Degrees. 5) Leather belting 75mm wide is to be used to transmit power between two parallel shafts which run at the same speed. The pulleys are 0.6 m diameter. At slow speeds the tension in the slack side is half the tension in the driving side and the angle of lap on the pulley is 180 degrees. If the maximum load on the belting is not to exceed 140 N/ cm of width, neglecting the effect of centrifugal force, estimate the maximum power which can be transmitted at 9.2 r/s. 6) Find the maximum torsional shear stress in a 75 mm diameter shaft transmitting 40 KW power at 1.33 r/s if the maximum twisting moment exceeds the minimum by 40 per cent. What is the greatest twist in degrees per metre length if G =87 GPa7) A mild steel shaft is required to transmit 35 KW at 2.33 r/s. Determine the shaft diameter assuming a maximum all shear stress of 65 MPa8) Mild steel is carried in two bearings and carries a sprocket which is subjected to a load of chain tension and its own weight which give a resultant force of 6000 N. If the sprocket transmits a power of 25 KW at 2.17 r/s determine the diameter of the shaft if it overhangs one of the bearings by 23 cm. Assume F(s) = 65 MPa and F (n) = 80 MPa9) Derive an expression for a suitable size of taper pi to carry a given load. Find the size of pin suitable for securing a sprocket to a 15mm diameter shaft, torque at the pitch circle diameter of the sprocket being 3.5 Kg m. Assume F(s) =n45 MPa.

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 Re: Engineering Design Maths questions. Re: Engineering Design Maths questions. -- Linksys20 Post Reply Top of thread Forum
 Posted by: zekeman ® 01/26/2005, 21:18:46 Author Profile eMail author Edit Where do these questions come from?

 Re: Engineering Design Maths questions. Re: Re: Engineering Design Maths questions. -- zekeman Post Reply Top of thread Forum
 Posted by: Linksys20 ® 01/27/2005, 14:49:13 Author Profile eMail author Edit Hello MateHopeall is well at your end! They come from a course I'm doing but can't get the hang of them, Do you think you could help.

 Re: Re: Engineering Design Maths questions. Re: Re: Engineering Design Maths questions. -- Linksys20 Post Reply Top of thread Forum
 Posted by: dylanwantssomehelp ® 11/29/2006, 09:02:18 Author Profile eMail author Edit Have got the exact same question for my test paper for ics course are u doing ics course stuck on them to up to question 6

 Re: Re: Re: Engineering Design Maths questions. Re: Re: Re: Engineering Design Maths questions. -- dylanwantssomehelp Post Reply Top of thread Forum
 Posted by: dylanwantssomehelp ® 11/29/2006, 09:09:10 Author Profile eMail author Edit For question 2 and question 3 look in ics course on section on bearings. Then look through it the bit about examples see the equation where d = 2.26 that is what u need for question 2 and question 3 is the last equation in bearing section on heat generated and specific load on journal. Have u covered this yet. Is it ics your doing as im doing it to