During lifting operations, truck-mounted cranes can suddenly lose stability or even tip over, causing accidents, due to factors such as excessive inertia caused by lifting excessively heavy objects, operating errors, sinking of the support surface, or excessive wind.
During lifting operations, truck-mounted cranes can suddenly lose stability or even tip over, causing accidents, due to factors such as excessive inertia caused by lifting excessively heavy objects, operating errors, sinking of the support surface, or excessive wind.
Causes of internal and external leakage in hydraulic cylinders:
1. Severe wear or deep grooves on the cylinder body, or cavitation areas on the cylinder inner wall. These can also be repaired using brush plating.
2. Wear of the piston rubber seal; in this case, it can be replaced.
3. Severe wear or grooves on the piston rod (or plunger) surface; these can be repaired using electroplating or metal brush plating.
4. Wear on the inner surface of the guide sleeve; due to their low price, guide sleeves are generally replaced.
Hydraulic Cylinder Inspection Method:
1. Use butter to stick a piece of paper to the extended piston rod. Measure the change in distance from the top of the paper to the end of the hydraulic cylinder, which is the amount of retraction of the hydraulic cylinder. 2. Use a releasable and relockable rubber plate to lock onto the piston rod. The measurement method is the same as using a piece of paper.
3. Use a dial indicator. Attach the magnetic base to the hydraulic cylinder piston rod, with the indicator needle resting on the end face of the cylinder barrel. Observe the change in the indicator needle 15 minutes after the engine is turned off (including the two methods below). This is the amount of retraction of the hydraulic cylinder.
There are many types of cranes, and the objects they lift are diverse, but they all have some basic, universally applicable stability technical requirements.
1. In the event of a sudden power outage during operation, return all control handles to zero. Before resuming operation, check that the crane is operating normally.
2. Cranes operating outdoors on rails should be anchored at the end of their work. When wind speeds exceed level 6, operations should generally be stopped and the crane anchored. For portal cranes operating along the coast, if wind speeds exceed level 7, operations should be stopped and the crane anchored. 3. Every crane operator must undergo training, pass the assessment, and hold an operator's license before being allowed to operate.
4. When taking over a shift, the crane operator should inspect the brakes, hook, wire rope, and stabilizer. Any abnormalities should be corrected before operation.
5. Before operating, a bell or alarm should be sounded. This should continue when approaching people during operation.
6. Operations should be carried out according to command signals. Upon hearing the emergency stop signal, regardless of who issues it, the emergency stop signal should be executed immediately.
7. Only turn off the main power supply after confirming that no one is on or near the crane. If the power disconnect device is locked or has a tag, it should be removed by the appropriate personnel before turning off the power supply.
8. Before turning off the main power supply, all controller handles should be in the zero position. Truck-mounted cranes operate in a variety of environments and under considerable pressure. Therefore, long-term operation is particularly susceptible to damage, including rust. Although truck-mounted cranes are generally made of stainless steel, it is not always rust-proof and can rust under certain conditions, affecting their service life.
Below, CNS will explain how to prevent rust on a 10-ton truck-mounted crane.
1. Regularly maintain the paint on the truck-mounted crane. Paint may flake after a period of use, compromising its effectiveness. Therefore, it is important to perform paint maintenance during crane disassembly and maintenance. Cranes should generally be inspected annually from multiple angles. If the paint surface is dull, rough, weathered, cracked (up to 25%), bubbling, or minor rust (up to 40%) on crane steel components is observed, immediate paint maintenance is indicated. 2. When applying the protective layer of paint to the crane, pay attention to the wiping method. The quality of wiping is the key to preventing rust problems on 10-ton truck cranes. When applying paint, you should apply the topcoat first, and then the paint to ensure that the two are properly matched and have good adhesion. In addition, according to the chemical properties of different paint types, choose the paint that is suitable for the matching, so that there is good adhesion between the topcoat and the paint to prevent the problem of paint falling off during the use process.
