For truck-mounted cranes, the crane component is of utmost importance. Any issues with the crane can have a significant impact on the overall performance of the truck-mounted crane. Therefore, it is essential to be familiar with some of the common fault problems that may occur with truck-mounted cranes. One such problem is the shaking of the crane’s boom when it is in the process of telescoping. So, what exactly is going on when this occurs? What are the possible causes that lead to this shaking? Let’s take a closer look.
Balance valve issues:
Balance valves are installed in the telescoping circuit of the boom of the truck-mounted crane. These valves play a crucial role in ensuring smooth and stable operation. However, if the damping hole of the balance valve becomes blocked, it can have a detrimental effect on the performance of the balance valve.
When the damping hole is blocked, the balance valve is unable to function properly. This can result in an imbalance in the hydraulic system, causing the boom to shake when telescoping. To address this issue, it is necessary to timely disassemble and clean the balance valve. By unblocking the damping hole, the balance valve can resume its normal operation, thereby reducing or eliminating the shaking of the boom.
For example, imagine a truck-mounted crane in operation. As the boom is being extended or retracted, the blocked damping hole in the balance valve disrupts the flow of hydraulic fluid. This leads to irregular pressure distribution, causing the boom to vibrate and shake. By identifying and addressing this problem promptly, the operator can ensure the safe and efficient operation of the crane.
Air in the hydraulic cylinder:
The presence of air in the hydraulic cylinder can also cause the boom of the truck-mounted crane to shake when telescoping. There are several possible reasons for air to enter the hydraulic circuit. If the liquid level in the hydraulic oil tank is too low, it can create a vacuum that draws in air. Additionally, if there is a leakage in the hydraulic circuit, air can also find its way into the system.
Once air enters the hydraulic circuit, it can have a significant impact on the performance of the hydraulic system. The air increases the elasticity of the oil and reduces the rigidity of the hydraulic transmission. This can lead to impact and crawling phenomena in the telescopic cylinder, ultimately causing the boom to shake.
To solve this problem, it is essential to find the fault point where air is entering the hydraulic circuit. This may involve inspecting all connections, seals, and components for leaks. Once the leak is identified and repaired, the air in the hydraulic circuit must be discharged. This can be done by using specific procedures such as bleeding the hydraulic system.
For instance, if a leak in a hydraulic hose allows air to enter the system, it can cause the boom to shake during telescoping. By replacing the damaged hose and properly bleeding the system, the operator can restore the stability of the crane’s operation.
Excessive friction during telescoping:
If the friction when the boom is telescoping is too large, it can lead to various problems. Excessive friction can cause the system pressure to fluctuate suddenly. This sudden pressure change can result in hydraulic shock, which in turn causes the boom to shake when telescoping.
Another factor that can contribute to excessive friction is severe wear of the boom slider. If the boom slider is worn down significantly, it can cause the boom to tilt downward when telescoping. This tilt can make the boom more prone to shaking.
To address these issues, several steps can be taken. Firstly, if the slider is severely worn, it should be replaced. Additionally, the gap between the boom and the slider should be adjusted to ensure it meets the specified value. Adjusting the slider gap without load is important so that it has an appropriate upward deflection value after the boom is extended. This upward deflection can compensate for the downward deflection that occurs when the boom is under load, thereby reducing the likelihood of shaking when the boom is telescoping.
For example, suppose a truck-mounted crane has been in use for a long time, and the boom slider has become severely worn. As the boom is telescoped, the excessive friction and downward tilt cause the boom to shake vigorously. By replacing the worn slider and adjusting the gap properly, the operator can restore smooth and stable operation.
Loose telescoping wire rope:
A loose telescoping wire rope of the boom can also be a cause of shaking. When the wire rope is not properly tensioned or has become loose over time, it can allow the boom to move irregularly, resulting in shaking.
To address this problem, the first step is to check the length and tension of the telescopic boom wire rope. Ensure that it meets the requirements specified by the manufacturer. Additionally, check the lubrication condition of the boom extension and retraction pulleys as well as the wear condition of the pulley bushings. If necessary, add lubricating grease or replace the pulley bushings.
For instance, if the wire rope is too loose and the pulleys are not properly lubricated, the boom may sway and shake during telescoping. By adjusting the wire rope tension and ensuring proper lubrication, the operator can minimize the shaking and improve the stability of the crane.
Poor processing technology:
Poor processing technology of the telescopic cylinder or the boom can also lead to shaking when telescoping. If the tolerance range between the various parts of the hydraulic cylinder is too large, it can result in an improper fit and cause the boom to move erratically. Similarly, if the processing technology of the boom is rough, it can lead to mismatches between the boom and the telescopic cylinder.
To solve this problem, in some cases, it may be necessary to replace the hydraulic cylinder. Additionally, strict quality control and proper processing techniques should be implemented to ensure that the boom and the telescopic cylinder are manufactured to precise specifications.
For example, if the hydraulic cylinder is poorly manufactured with excessive tolerances, it can cause the boom to shake when telescoping. By replacing the faulty cylinder with one of better quality or by improving the manufacturing process, the operator can ensure a more stable operation.
Poor lubrication of the boom slider and lubrication channel:
Poor lubrication of the boom slider and lubrication channel can also contribute to the shaking of the boom when telescoping. Without proper lubrication, the friction between the boom and the slider can increase, leading to irregular movement and shaking.
To address this issue, it is important to regularly check the lubrication condition of the slider and slideway. Apply lubricating grease in a timely manner to reduce the telescopic resistance and prevent the boom from shaking.
For instance, if the lubrication is neglected and the slider becomes dry and rough, the boom will experience increased friction and is more likely to shake during telescoping. By maintaining proper lubrication, the operator can ensure smooth operation and prolong the life of the crane components.
Shaking of the boom when telescoping is indeed a very serious fault. When your truck-mounted crane exhibits such a fault, it must be dealt with promptly. Failure to address this issue in a timely manner can lead to serious consequences, such as reduced lifting capacity, damage to the crane components, and even potential safety hazards. By understanding the possible causes of boom shaking and taking appropriate measures to address them, you can ensure the reliable and safe operation of your truck-mounted crane.
