When hoisting a long string of insulators, care should be taken not to ? because it can damage the ball, socket, and cotter keys.

• A. Excessively bend the string
• B. Send up the entire string
• C. Split the string
• D. Tie the rope to the insulators

Answer: (A)

The main idea is that insulator strings are designed to flex only within a safe range, and the ball-and-socket joints with cotter keys are vulnerable to damage if bent too sharply during hoisting. Excessive bending puts a bending moment on those joints, distorting the ball or socket and risking loosened or sheared cotter keys. Once those components are compromised, the string can lose its integrity and alignment, creating a serious safety hazard when it’s in service. To prevent this, keep the string as straight as possible during hoisting and use proper rigging to manage any needed angles, avoiding sharp bends.

The other options don’t address the failure mechanism described. Hoisting the entire string up doesn’t inherently harm the joints, splitting the string is a different handling method, and tying rope to the insulators isn’t the issue at stake here. The key point is preserving the joints by avoiding excessive bend.