Maximum Static Wheel Load 2

[joelperez]

Kind Regards, can somebody explain to me how the crane manufacturer calculate the maximum wheel load
that appears on the crane's specs?
Thanks in advanced.

 

[DaveAtkins]

They consider the lifted load, the weight of the trolley, and the weight of the bridge crane. The lifted load and the trolley are positioned to give the maximum effect.

DaveAtkins

 

[phamENG]

Check out this document I found using google:

Crane Supporting Steel Structures - Design Guide

I think Chapter 2 will provide you with some good insights.

 

[joelperez]

Thank you all.
I've been reading the AISC Design Guide and the definition of maximum wheel load is exactly the one that you gave me @daveatkins and I was trying to do an analysis to get the same result but I dont know what I'm doing wrong because I'm getting a different number. These are the numbers on the crane specs:
Crane capacity: 50 ton = 50,000kg
Total Bridge Weight: 17,500 kg
Hoist and Trolley Weight: 6,000 kg
Max Static Wheel Loading: 154 kN per wheel (for 8 wheel arrangement) = 15,700kg

I supposed that the maximum wheel load will be when the trolley is placed at one end of the bridge. Im getting this result:

At one end I will have:
Trolley
6000 kg/4=1500kg per wheel because the whole trolley weight will be at one end and one end has 4 wheels)
Bridge
17500 kg/2 = 8750kg (8750/4=2187.5 kg per wheel at one end when the trolley is located at that end)
Lifted Weight
50,000/4 = 12,500kg per wheel at one end when the trolley is located at that end.

The maximum wheel would be: 16,187.5kg per wheel at one end.

 

[DaveAtkins]

The difference is that a small portion of the trolley weight, and a small portion of the lifted load, goes to the opposite end of the bridge crane--because they are not directly over one end of the bridge crane, they are a short distance from one end of the bridge crane.

DaveAtkins

 

[joelperez]

Got it, thank you!