Fleet angles shall not be more than how many degrees?

Fleet angles shall not be more than how many degrees?

• A. 1 degree
• B. 1 1/2 degrees
• C. 2 degrees
• D. 3 degrees

Answer: (B)

Fleet angle is the angle formed by the rope as it leaves the hoist drum and heads toward the next pulley. Keeping this angle small reduces bending stress on the rope, minimizes edge wear on the drum and guides, and helps the rope wear evenly instead of rubbing on one side. In mining hoisting practice, the maximum permissible fleet angle is one and a half degrees. If the angle gets larger, the rope wears faster, can ride up on the drum edge, and its life and safety can be compromised. That’s why smaller values like one degree would be overly conservative in some setups, while larger values such as two or three degrees exceed the safe limit and increase the risk of rope damage and failure. Therefore, the allowed maximum is one and a half degrees.

Fleet angle is the angle formed by the rope as it leaves the hoist drum and heads toward the next pulley. Keeping this angle small reduces bending stress on the rope, minimizes edge wear on the drum and guides, and helps the rope wear evenly instead of rubbing on one side. In mining hoisting practice, the maximum permissible fleet angle is one and a half degrees. If the angle gets larger, the rope wears faster, can ride up on the drum edge, and its life and safety can be compromised. That’s why smaller values like one degree would be overly conservative in some setups, while larger values such as two or three degrees exceed the safe limit and increase the risk of rope damage and failure. Therefore, the allowed maximum is one and a half degrees.