Although there are many types of cranes and the objects they lift are diverse, they all have some basic and generally applicable stability technical requirements.
Two points to note when inspecting the performance of cranes:
I. Amplitude Variation Mechanism
1. Debugging condition: The basic boom and the lifting boom have an elevation Angle of 50°. Stop after lifting the rated lifting capacity under this working range to a height of 1 meter.
2. Debugging requirements: The crane must ensure that the relevant mechanisms operate smoothly during lifting operations, with accurate movements and no phenomena such as crawling, vibration, impact, or abnormal increase in driving power. The point operation performance of the hoisting, slewing, and luffing mechanisms should be good.
3. Debugging method: Move the control handle to the lifting (lowering) position of the boom. Brake immediately when the load moves slightly. Lift and lower the boom 10 times continuously, measure the cumulative distance of the horizontal movement of the load, and calculate the average displacement of each action of the boom lifting and lowering respectively. The value should conform to the specified value; otherwise, the braking performance and cost of the brake (wire rope luffing mechanism) or the set pressure of the back pressure balance valve and secondary control valve in the hydraulic circuit (hydraulic cylinder luffing) should be adjusted.
Ii. Hoisting Mechanism and Slewing Mechanism
1. Debugging method: Rotate the control handles respectively to the working positions for lifting, lowering, turning left, and turning right. Immediately apply the brake when the load or the rotating part of the crane moves slightly. Continuously raise and lower the boom 10 times. Measure the cumulative lifting and lowering distances or the arc length of rotation of the load, and calculate the average lifting, lowering, and rotation angles of the load each time. They should not exceed the specified values; otherwise, the usability and performance of the brake should be adjusted.
2. Debugging conditions: Basic boom, small working amplitude, lifting large rated lifting capacity, stop when lifted to about 1 meter.
The motor, bracket and steel wire rope are important components of the small crane. The structure that directly affects the stability of the small crane is the main frame. The quality of the main frame is not only determined by the materials used, but more importantly, it is inseparable from its welding technology. The welding method adopted by the main frame of the small crane is not ordinary welding technology, but seamless welding technology. So, what is seamless welding technology?
The welding process and the role of the welding head are inseparable. The welding head in seamless welding technology is an acoustic device that directly transmits mechanical vibration energy to the products to be bonded. Vibration is transmitted to the bonding surface through the welding workpiece. The vibration friction generates heat energy, causing the plastic to melt. The vibration stops when the molten material reaches its interface. Briefly maintaining pressure can cause the molten material to form a strong molecular bond when it solidifies at the bonding surface. The entire cycle is usually completed in less than a second, but the welding strength is close to that of a single piece of material.
What are the more prominent features of seamless welding technology?
Seamless welding technology not only helps to remove the weld seams of the main frame of the small crane, but also correspondingly improves the precision, smoothness and appearance of the parts. Meanwhile, seamless welding technology has implemented good rate control in the injection molding process, shortening the processing cycle of the mold. Due to the high surface finish of the products produced by this process, there is no need for secondary spray plating and annealing, thus avoiding dimensional changes caused by secondary shrinkage.
Although there are many types of cranes and the objects they lift are diverse, they all have some basic and generally applicable stability technical requirements.
1. The driver of each crane must undergo training, pass the assessment and hold an operation certificate before being allowed to operate.
2.Before driving, it is necessary to ring the bell or call the police. When approaching people during operation, a continuous ringtone or alarm should also be given.
3.When a sudden power outage occurs during work, all controller handles should be returned to the zero position. Before resuming work, it is necessary to check whether all the crane movements are normal.
4.When a crane operating in the open air on the track finishes its work, it should be anchored. When the wind force exceeds level 6, work should generally be stopped and the small crane anchored. For portal cranes operating along the coast, when the wind force exceeds level 7, work should be halted and the cranes anchored.
5.When the driver conducts maintenance and repair on the crane, he should cut off the main power supply and hang a signboard or lock it. When live repair is required, one should wear insulating gloves, insulating shoes, use tools with insulating handles, and have someone supervise.
6. Operations should be carried out in accordance with the command signals. Upon hearing the emergency stop signal, no matter who gives it, it should be executed immediately.
7.When the small crane driver takes over the shift, he should inspect the brake, hook, steel wire rope and stabilizing device. If abnormal performance is found, it should be eliminated before operation.
8.Before closing the main power supply, all controller handles should be set to zero position.
9. The main power supply can only be closed when it is confirmed that there is no one on or around the small crane. If the power circuit breaker is locked or marked with a sign, it should be removed by relevant personnel before the power is closed.
