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 Shaft Diameter Calculations Post Reply Forum
 Posted by: mikee122 ® 04/27/2007, 16:04:08 Author Profile eMail author Edit I am looking for either a simple formula or simplified formulas to determine the min. shaft diameter. For example I know the torque vaule, the type of loading (repeated torsion), the length of the shaft with the maximum amount of Angle of twist.T=50,000 Loading = 4 Shaft length = 20 foot Max AOT = 10 degreesI plan on using 4140 Steel, normalized (TS 148,000 psi, YS 95,000 psi)In the event there are several formulas please list in a logical order

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 Re: Shaft Diameter Calculations Re: Shaft Diameter Calculations -- mikee122 Post Reply Top of thread Forum
 Posted by: bobthedog ® 04/29/2007, 12:46:41 Author Profile eMail author Edit Hey just wondered are u doing the ics engineering course To proceed mike Torque is measured in kjoules 1000 joules equal one killer jouleLoading 4 what does that mean 4 whatAlso is with that steel 4140 TS AND YS is YS YIELD STRENGTH WHAT IS TS ???Got about 4 equations for u but wanted to find that out ok cheers. DONT GIVE UP THE FAITH

 Re: Re: Shaft Diameter Calculations Re: Re: Shaft Diameter Calculations -- bobthedog Post Reply Top of thread Forum
 Posted by: bobthedog ® 04/29/2007, 13:03:59 Author Profile eMail author Edit Torque is also measured in oz aswell sorry onces Can u help with this how to work out 1/16 of an inch and 3/16 of an inch on a calculator etc how its put onto the calculator and to doAlso m2 is meteres squared but m 3 is meters cubed where on the calculator is meters cubed button thanks DONT GIVE UP THE FAITH

 Re: Shaft Diameter Calculations Re: Shaft Diameter Calculations -- mikee122 Post Reply Top of thread Forum
 Posted by: materialboy ® 04/28/2007, 07:21:34 Author Profile eMail author Edit The diameter is with in ur values.Torque = radius * perpendicular force Fwhere Loading gets to be the perpendicular force because it is the shaft.What value is loading of 4 ???r = Torque/ Force F

 Re: Re: Shaft Diameter Calculations Re: Re: Shaft Diameter Calculations -- materialboy Post Reply Top of thread Forum
 Posted by: mikee122 ® 04/28/2007, 11:44:12 Author Profile eMail author Edit Could you please clarify. I am trying to determine the diameter. I don't have a diameter value In r=Torque/Force would not the Torque be equal to the perpendicular loading?I am referencing a chart that states that shows the loading value based on the type of loading.Manner of loading Design factor Design shear stress T sub d= s sub y/2N ________________________________________________________________ Static or steady torsion 2 T sub d= s sub y/4 repeated torsion 4 T sub d= s sub y/8 torsion impact or shock 6 T sub d= s sub y/12 T=50,000 Loading = 4 Shaft length = 20 foot Max AOT = 10 degreesI did make a minor change to the material I would like to use.I plan on using 4140 Steel,OQT 700 (US 231 ksi/1593 MPa, YS 212 ksi/1462 MPa)

 Re: Re: Re: Shaft Diameter Calculations Re: Re: Re: Shaft Diameter Calculations -- mikee122 Post Reply Top of thread Forum
 Posted by: materialboy ® 04/29/2007, 11:43:49 Author Profile eMail author Edit How far I understand, Torque = Radius*Prependicular Force So, in your question, Force will be created by perpendicular loading. Hence, if your loading is acting prependiculary than yes it will replace perpendicular force. Manner of loading Design factor Design shear stress T sub d= s sub y/2N ???_________________________What does your [s sub y/2N] stands for ???_____________________________________

 Re: Re: Re: Re: Shaft Diameter Calculations Re: Re: Re: Re: Shaft Diameter Calculations -- materialboy Post Reply Top of thread Forum
 Posted by: mikee122 ® 04/29/2007, 15:58:43 Author Profile eMail author Edit I am doing a strength of materials course fir Mech. Design.Our text book is Strength of Materials, 4th edition by Robert L Mott The table is Manner of loading | Design factor | Design shear stress | | T sub d= s sub y/2N ______________________________________________________________ Static or steady | 2 | T sub d= s sub y/4 torsion | | _____________________________________________________________ repeated torsion | 4 | T sub d= s sub y/8 _____________________________________________________________ torsion impact | 6 | T sub d= s sub y/12 shock _____________________________________________________________T=50,000 lb-ft Loading = 4 Shaft length = 20 foot Max Angle Of Twist = 10 degreesI plan on using 4140 Steel,OQT 700 (US 231 ksi/1593 MPa, YS 212 ksi/1462 MPa) US = Ultimate Strength , YS = Yield StrengthT sub d= s sub y/2N is the formula for Design shear stress. In the formula (Torque = Radius*Prependicular Force) Would Radius=50,000lb-ft/4(the design factor of 4)???

 Re: Re: Re: Re: Re: Shaft Diameter Calculations Re: Re: Re: Re: Re: Shaft Diameter Calculations -- mikee122 Post Reply Top of thread Forum
 Posted by: materialboy ® 04/30/2007, 06:56:12 Author Profile eMail author Edit Well if you understand the meaning of MPa and stress, u won't ask on the prependicular.Ur answer is with in the statement u have just written.