Given force, need to determine what bearing to use for a crane

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erobz said:
Explain how its in static equilibrium with an unbalanced horizontal force component from the support and the tension on the pulley?
The beams are in static equilibrium since they are in rest state but yeah i guess with the pulleys its not in equilibrium once it starts to lift, when we stop the winch then its in static equilibrium.
 
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What do you mean by an "unbalanced horizontal force"? Why cant you just assume the forces is right i dont really get this.
 
salamikorv said:
What do you mean by an "unbalanced horizontal force"?
The forces in the horizontal direction are unbalanced. The beam is not in static equilibrium with the loading your supervisors told you was correct.
salamikorv said:
Why cant you just assume the forces is right i dont really get this.
?? Do you wan't to find the actual loading on your mounting bracket?
 
erobz said:
The forces in the horizontal direction are unbalanced. The beam is not in static equilibrium with the loading your supervisors told you was correct.

?? Do you wan't to find the actual loading on your mounting bracket?
Im fine with the forces i have and what the studentassistant has told us, no offense by the way. I dont want to say my mates calculations are wrong since he has got a lot of help from the assistants , if i asked for help of an exercise in my book with these information given would you just ignore the information given and find it yourself? (poorly explained but i think you understand what im saying here). Just assume its 30kN directed as i drew it and 20kN on the side like i drew it, its alright. All i wanna understand is how to determine the bolts.
 
salamikorv said:
Im fine with the forces i have and what the studentassistant has told us, no offense by the way. I dont want to say my mates calculations are wrong since he has got a lot of help from the assistants , if i asked for help of an exercise in my book with these information given would you just ignore the information given and find it yourself? (poorly explained but i think you understand what im saying here). Just assume its 30kN directed as i drew it and 20kN on the side like i drew it, its alright. All i wanna understand is how to determine the bolts.
Sizing the bolts requires having as close to an accurate loading as reasonably possible. If you don't care about having accurate loads, then why do you care about sizing the bolts accurately?

Imagine for a moment you are an engineer and you are designing a bridge that your family will travel everyday, and many others families will travel... And you say, but I don't care about the loads being accurate, I just care about sizing these bolts that hold the bridge up...SMH.

Maybe I'm wrong. I'll just gracefully bow out and let someone else help you.
 
erobz said:
Sizing the bolts requires having as close to an accurate loading as reasonably possible. If you don't care about having accurate loads, then why do you care about sizing the bolts accurately?

Imagine for a moment you are an engineer and you are designing a bridge that your family will travel everyday, and many others families will travel... And you say, but I don't care about the loads being accurate, I just care about sizing these bolts that hold the bridge up...SMH.

Maybe I'm wrong. I'll just gracefully bow out and let someone else help you.
Hhahaha yeah but im pretty confident he hasnt done any mistakes. Look, i can discuss this with him later on but i came here to get help from the problems i got, and that is to determine the bolts. If you re-did the calculations and got something else thats fine, but im only for understanding how to get the bolts. I dont get why you are so passionate about re-doing it, there's plenty of cranes with those exact loads he got, why cant you just help me understand how to get dimension the bolts, not even the loading but the general steps as in the formulas like Baluncore showed, i didnt give him numbers but he showed one way of determing the bolts. Let the force thats in compression be called K, no number, and the other force Q, so i got two loads. What principle/method do i have to use in order to determine the bolts?
We dont have much time, im not going to use an hour to re-do his calculations in order for you to just show the method of determining bolts in a crane situation like this. Just having this conversation has been taking way more than an hour.
 
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I have this crane that has to be able to lift a weight of maximum 1000kg. Its a type of a manual winch crane thats going to be able to rotate. I need help with the rotating part, i want to determine the bearings inside this rotating part and im thinking to use 2 bearings in there but im not sure if you can use welding on the edge of the bearings and make it stuck? And how i should determine them.
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The bearing system will need to support both axial and radial loads. Why do you have four different bearing surfaces? Why are the two "bearings" so close together? What experience do you have in objects that weigh a ton? Perhaps you can work with someone locally.

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I backed out at post #40, after the base went from square to round, without rational discussion. I now know this is a poorly organised school exercise, we were dealing with a hidden committee, while communicating through a bottleneck. It is still my opinion that, without clear labelled drawings, discussion is a waste of time.
 
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