Deck Crane Wire Rope Replacement

Criteria for deck crane wire replacement include broken wires exceeding 10% of the total wire count within a single lay pitch, wear or corrosion exceeding 40% of the original diameter, complete strand breakage, or a diameter reduction of 7% or more.

A wire rope must be replaced if any of the following conditions occur:

1.Excessive wire breakage: The number of broken wires within a single lay pitch (approximately 8-10 times the wire rope diameter) reaches 10% of the total wire count. For example, a 6×19 structure (114 wires) has 12 or more broken wires. When mixed thick and thin wires are used, broken thick wires are counted as 1.7.

2.Wear or corrosion: Radial wear or corrosion exceeding 40% of the original diameter. If less than 40%, the rope can be scrapped by reducing the number of broken wires.

3.Structural deformation: Cage-like distortion, hairpin deformation, spiral necking exceeding 1/3 of the original diameter, strand breakage, or loose strands.

4.Diameter change: A diameter reduction of 7% or more, or a localized reduction of 10% or more accompanied by corrosion.

5.Other defects: Exposed hemp core, significant corrosion, and permanent twisting and deformation.

Inspection and Maintenance Requirements

1.Daily Inspection: Before each use, visually inspect for broken wires, wear, and deformation, focusing on stress concentration areas such as the rope ends and near the pulleys.

2.Regular Professional Assessment: Conduct assessments every six months or as specified by the manufacturer. Measure the diameter and record the rate of increase in broken wires. Accelerated breakage due to fatigue requires a shorter assessment period.

3.Special Scenarios: When lifting hot metal or hazardous materials, the scrap standard should be half the normal value.

Replacement Procedures

1.Preparation: Study the instructions, conduct a risk assessment, and prepare tools (wrench, hoist, wire mesh, etc.). Release the limiter and secure the moving pulley.

2.Removing the old wire: Remove the lute head pin and pull the old wire to the deck with a rope. Secure the old wire with 2-3 turns remaining on the drum and remove the fixing screws.

3.Installing the new wire: Connect the old and new wires using a special mesh or welding. Apply wire oil and ensure a tight alignment when twisting the new wire in. After securing, remove the connecting device. 4.Final test: Install the pipa head and tighten it, test the torque and limit function after restoring the limit, and clean up the site.