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EspElement
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My problem is proving my structure is sound. Currently i want to know my deflection from my loads applied.
See attachment. My load is 4000 lb. My carriage weight is 1200 lb. My upright column or tube is a 6" x 4" x 1/4" structural steel which i have 2 of these. I have distances to my CoG (Center of Gravity) of the carriage. I'm not sure if this is the variable i need or not for this.
I started with deflection of a cantilevered beam. Deflection = PL^3/3EI. I attempted to use torque ratios to determine my load. Shown I have 25.125" = X and 87.1875" = Y. So i took 25.125/87.1875 ~ 0.288. I then used that value to my calculations for the load on the column. 5200 * .288 ~ 1500 lb.
I of beam3 is ((6^3)(4)-(5.5^3)(3.5))/12 ~ 23.5 * 2 = 47in^4
(1500)(87^3)/(3)(30 mil)(47) ~ 0.234"
The reason I raise this question is 1 it seems unlikely the deflection is that high, I could be wrong and 2 i want to prove that value i have calculated is correct.
I think the correct way to do this is by an eccentrically loaded column formula but i can't seem to gather enough information in my young career to evaluate that.
Notes:
I put a SF into the load from 2000 to 4000. Obviously a 1/4" sounds like a lot and is certainly not acceptable. The actual value would be like 1/8" if this is calculated properly which is still not ideal. I also am not considering the tracks I and other components within the design for this calculation.
If anyone can back me up or guide me in the proper direction that would be great! Thanks in advance.
See attachment. My load is 4000 lb. My carriage weight is 1200 lb. My upright column or tube is a 6" x 4" x 1/4" structural steel which i have 2 of these. I have distances to my CoG (Center of Gravity) of the carriage. I'm not sure if this is the variable i need or not for this.
I started with deflection of a cantilevered beam. Deflection = PL^3/3EI. I attempted to use torque ratios to determine my load. Shown I have 25.125" = X and 87.1875" = Y. So i took 25.125/87.1875 ~ 0.288. I then used that value to my calculations for the load on the column. 5200 * .288 ~ 1500 lb.
I of beam3 is ((6^3)(4)-(5.5^3)(3.5))/12 ~ 23.5 * 2 = 47in^4
(1500)(87^3)/(3)(30 mil)(47) ~ 0.234"
The reason I raise this question is 1 it seems unlikely the deflection is that high, I could be wrong and 2 i want to prove that value i have calculated is correct.
I think the correct way to do this is by an eccentrically loaded column formula but i can't seem to gather enough information in my young career to evaluate that.
Notes:
I put a SF into the load from 2000 to 4000. Obviously a 1/4" sounds like a lot and is certainly not acceptable. The actual value would be like 1/8" if this is calculated properly which is still not ideal. I also am not considering the tracks I and other components within the design for this calculation.
If anyone can back me up or guide me in the proper direction that would be great! Thanks in advance.