Crawler crane wire rope, also known as hoist rope or lifting rope, plays a crucial role in the operation of crawler cranes. Constructed from multiple strands of high-strength steel wires twisted together, this robust and flexible cable enables the crane to perform various lifting and hoisting tasks. As the primary means of lifting heavy loads, the crawler crane rope provides the necessary strength, stability, and load-bearing capacity.
Wire rope fraying is a significant concern in the operation of crawler cranes, but with proper understanding and preventive measures, it can be effectively managed.
The fraying reasons of crawler crane rope
When operating crawler cranes, crane wire rope fraying poses a significant challenge that can compromise safety and efficiency. There are several reasons that cause crawler crane rope fraying, including friction and abrasion, overloading, and heat exposure.
The friction & abrasion reason of crane wire rope
The continuous movement of the wire rope against various components during crane operation creates friction. Over time, this friction can lead to wear and tear, causing the crane wire rope to fray. Factors such as improper rope alignment, contact with sharp edges or rough surfaces, and inadequate lubrication can exacerbate friction-related fraying.
crane wire rope overloading
One of the primary causes of wire rope fraying is overloading the crawler crane. When the crane is subjected to loads beyond its rated capacity, the steel cable experiences excessive tension and stress. This can lead to wire breakage, strand distortion, and ultimately result in fraying of the rope.
Heat exposure
Crawler cranes operating in environments with high temperatures or prolonged exposure to sunlight are susceptible to wire rope fraying. Heat can cause the crane wire rope to expand, lose its structural integrity, and deform. Such deformation weakens the rope, making it more prone to fraying and failure.
How to prevent Crane wire rope fraying?
To effectively manage wire rope fraying in crawler cranes, implementing preventive measures is crucial. By being proactive and adopting strategies to address the main causes of crawler crane rope fraying, crane operators can ensure safe and efficient operations.
Lifespan awareness of crane wire rope
As a crucial component of crawler cranes, the crane wire rope should be regularly replaced to avoid fraying caused by exceeding its lifespan.
The scrapping criteria for crawler crane wire rope
The scrapping criteria for crawler crane wire ropes mainly include the following points:
Criteria for the number of broken wires
If the number of broken wires within a lay length reaches 10% of the total number of wires in the wire rope, it should be scrapped. For example, for a 6×19 construction wire rope (with 114 wires), it should be scrapped when the number of broken wires reaches 12. For a 6×37 construction wire rope (with 222 wires), it should be scrapped when the number of broken wires reaches 22. When calculating the number of broken wires in wire ropes composed of different size wires, each fine wire is counted as one, and each thick wire is counted as 1.7.
Criteria for wear or corrosion
If the radial wear or corrosion of the wire exceeds 40% of its original diameter, it should be scrapped. When it is less than 40%, the number of broken wires can be reduced according to regulations before scrapping.
Criteria for diameter variation
If the steel cable diameter decreases by 7% or more relative to the nominal diameter, even without any broken wires, the wire rope should be scrapped.
Other damage conditions
This includes complete rope strand breakage, exposed core, significant corrosion, and localized outer wire elongation in a cage-like shape. In such cases, the wire rope should be scrapped.
Consideration of safety factors
For rotation-resistant wire ropes used as hoist rope and lifting rope, where the safety factor is 6 or 7, the number of broken wires within a lay length must not exceed 10% of the total number of wires.
Other preventive measures of crane wire rope fraying
Avoiding overloading
To prevent overloading incidents, crane operators should strictly adhere to the crane’s load capacity limits and follow safety operating procedures. This includes accurately calculating the weight of the load, considering factors like the boom angle and radius, and ensuring that the load falls within the crane’s safe working range. Regular training programs should be implemented to educate crane operators about load management techniques, emphasizing the importance of staying within the crane’s rated capacity to prevent excessive strain on the wire rope.
Enhanced inspection
Regular inspections are essential to identify any signs of wear, damage, or fatigue in the steel cable. Inspections should be conducted before each use and at regular intervals as recommended by the manufacturer or industry standards. During these inspections, close attention should be given to areas prone to wear, such as the drum, sheaves, and connections. If any signs of crawler crane rope wear, such as broken wires, corrosion, or significant diameter reduction, are detected, the wire rope should be promptly replaced to ensure safe operation.
Preventing heat exposure
Heat exposure can have detrimental effects on the steel cable, leading to accelerated wear and fraying. To prevent this, measures should be taken to shield the wire rope from direct sunlight and high temperatures. This can be achieved by using protective covers or insulation materials on the wire rope and ensuring proper storage when the crane is not in use. Additionally, scheduling crane operations during cooler periods of the day or providing shaded work areas can help minimize heat exposure and reduce the risk of wire rope damage.
Regular maintenance
Implementing a comprehensive maintenance program is crucial for wire rope longevity. This includes regular lubrication to reduce friction and wear, as well as periodic cleaning to remove dirt and debris that can cause abrasion. Proper storage practices should be followed to protect the wire rope from environmental factors such as moisture and corrosive substances. Additionally, conducting thorough inspections of other crane components, such as sheaves, drums, and hooks, can help identify potential issues that may indirectly impact the wire rope’s condition.
Choose best crane wire rope at Value Crane
