What caused the cable to break during the lifting of a 4500kg container?

Click For Summary
SUMMARY

The investigation into the cable break during the lifting of a 4500kg container reveals that the cable, rated for a maximum tension of 50,000N, failed despite the load being within limits. Calculations show that the tension experienced by the cable was 48,645N, which is below its safety rating. The crane's operational parameters, including a maximum speed of 3.0m/s and acceleration of 1.0m/s², were not exceeded, confirming that the crane itself was not defective. Therefore, the conclusion is that the cable was defective, leading to the failure.

PREREQUISITES
  • Understanding of basic physics principles, particularly tension and weight calculations
  • Familiarity with crane operation parameters, including speed and acceleration limits
  • Knowledge of material properties, specifically the safety ratings of lifting cables
  • Ability to perform calculations involving forces and accelerations
NEXT STEPS
  • Research the properties and testing standards for steel cables used in lifting applications
  • Learn about the calculations involved in determining maximum load capacities for cranes
  • Explore safety protocols and maintenance practices for lifting equipment
  • Investigate common causes of cable failures in lifting operations
USEFUL FOR

Engineers, safety inspectors, crane operators, and anyone involved in lifting operations or equipment safety assessments will benefit from this discussion.

ixbethxi
Messages
13
Reaction score
0
You've been called to investigate an accident in which a cable broke while lifting a 4500kg container. The steel cable is 2.0cm in diameter and has a safety rating of 50,000N. The crane is designed not to exceed speeds of 3.0m/s or accelerations of 1.0m/s^2, and your tests find the crane is NOT defective. what is your conclusion? did the crane operator life too heavy a load or was the cable defective.

can someone check my solution? i don't know if its right

the max tension the cable can hold is 50,000N

T-((4500kg)*(9.81m/s/s))=4500(1.0m/s/s)

T= 48,645<50,000 which means the cable must of been broken because it could possibly hold more.
 
Physics news on Phys.org
What about speed, vertical or horizontal?
 
ixbethxi said:
You've been called to investigate an accident in which a cable broke while lifting a 4500kg container. The steel cable is 2.0cm in diameter and has a safety rating of 50,000N. The crane is designed not to exceed speeds of 3.0m/s or accelerations of 1.0m/s^2, and your tests find the crane is NOT defective. what is your conclusion? did the crane operator life too heavy a load or was the cable defective.

can someone check my solution? i don't know if its right

the max tension the cable can hold is 50,000N

T-((4500kg)*(9.81m/s/s))=4500(1.0m/s/s)

T= 48,645<50,000 which means the cable must of been broken because it could possibly hold more.

Yes. You are somehow right.

If u were to work out the acceleration allowed to lift the weight. 50000-(4500*9.81)= 4500a By working out a, u will get the max acceleration allowed for the lifting of the mass. From there, you can see that the acceleration is more than that of those specified in the qn. Thus, its not that the mass is too heavy but its due to the defective cable.
 
ixbethxi said:
... and your tests find the crane is NOT defective. what is your conclusion?...
 
i concluded that it waas the cable that was defective
 

Similar threads

What is the tension in the lift cable and in the string?
  • · Replies 19 ·
Replies
19
Views
4K
What Are the Tensions in the Cables When a Crane Lifts a Load?
  • · Replies 1 ·
Replies
1
Views
4K
Undergrad What is the correct way to calculate the power required to lift a mass?
  • · Replies 25 ·
Replies
25
Views
11K