Overhead Crane Practice Test

According to ASME B.30.2, what is the minimum number of wraps on the hoisting drum without a lower limit device?

1. Four wraps

2. Two wraps

3. Three wraps

4. At least two wraps

The correct answer is: At least two wraps

The requirement according to ASME B.30.2 states that when operating an overhead crane, it is essential to maintain at least two wraps of rope on the hoisting drum when there is no lower limit device present. This guideline is crucial for ensuring sufficient rope security and preventing slippage or disconnection, which could lead to dangerous situations during lifting operations. Having at least two wraps ensures that there is enough friction and grip, which is vital for the hoist mechanism to function correctly under load. With fewer than two wraps, the chances of the rope slipping off the drum increase, particularly if the load shifts or if there are any sudden movements. Therefore, maintaining a minimum of two wraps is a safety measure to promote operational integrity and protect both the equipment and personnel involved in overhead lifting operations.