Maintenance and Troubleshooting Flashcards

When inspecting wire rope, what condition requires immediate removal from service?

Answer: Six randomly distributed broken wires in one rope lay

Six or more randomly distributed broken wires in one rope lay is a disqualifying condition per ASME B30.2 standards.

A crane's load line sheave shows excessive groove wear. What is the primary risk if it continues in service?

Answer: Increased rope wear and potential wire damage

Worn sheave grooves cause accelerated wire rope wear by creating high contact stress on individual wires.

What does a milky or foamy appearance in hydraulic fluid indicate?

Answer: Water contamination

Milky or foamy hydraulic fluid indicates water contamination, which reduces lubrication and can cause cavitation.

During a functional test after maintenance, the crane's swing brake does not hold on a slope. What is the most likely cause?

Answer: Worn or improperly adjusted brake linings

Worn or maladjusted brake linings reduce clamping force, preventing the swing brake from holding the superstructure on a grade.

Which lubrication point on a lattice boom crane requires grease at the most frequent interval?

Answer: Boom pin connections

Boom pin connections experience continuous dynamic loading and must be greased most frequently to prevent galling and wear.

A hoist drum shows spiral grooving damage. What operational condition most likely caused this?

Answer: Rope wrap-on under load without fleet angle control

Improper fleet angle during spooling causes the rope to cross-wind and dig into previously wound layers, creating spiral groove damage.

A load moment indicator (LMI) gives an erratic reading. Which step should be performed first during troubleshooting?

Answer: Check all sensor connections and cable integrity

Loose or damaged sensor connections are the most common cause of erratic LMI readings and must be checked before replacing components.