The dangers of misunderstandings in the operation and use of wheel loaders

2023-09-25

In the field of engineering and construction, China-made wheel loaders, as an important construction machinery, are widely used in material handling and earthmoving projects. However, despite the impressive functions and efficiency of the loaders, in actual operation , we often overlook some key usage misunderstandings. These misunderstandings may not only lead to equipment failure and performance degradation, but also increase risks to operational safety. Therefore, it is crucial to understand and avoid these common wheel loader usage misunderstandings.



1. Press the accelerator as soon as you start.

When the wheel loader engine is just started, the body temperature is low, the oil viscosity is high, and the fluidity is poor. The oil cannot flow smoothly to various lubrication points in a short period of time. If the throttle is increased at this time, the engine speed will increase instantaneously. Although the oil supply volume and pressure of the oil pump will also increase, the lubricating oil volume and oil pressure requirements of each kinematic pair cannot be met instantly, and the kinematic pair cannot establish a stable level. A good lubricating oil film produces instantaneous dry friction, leading to severe wear. If each moving pair is poorly lubricated, the running resistance will also increase. If the accelerator is hit hard, the piston, connecting rod, and crankshaft will violently impact, accelerating damage to the parts. In addition, for diesel engines equipped with turbochargers, the oil seals can easily be damaged due to poor lubrication, leading to turbocharger failure and reduced diesel engine power. Therefore, after the loader is started, it should run smoothly and at low speed (about 500-700 r/min), and it is strictly forbidden to increase the throttle too much.



2. Directly replenish cooling water during operation

Insufficient cooling water will cause the diesel engine to overheat due to lack of water. Directly replenishing cooling water when a diesel engine is at high temperature will cause a large temperature difference in the entire cooling system, causing the cylinder head, cylinder liner, cylinder block, etc. to become brittle instantly, causing micro-cracks, and gradually leaking cooling water, resulting in oil and gas leaks. Therefore, when the temperature of the diesel engine is too high, it should be run with no load at a slightly higher speed. When the water temperature drops to about 50°C, turn off the engine, unscrew the radiator cover, discharge the water vapor, and slowly inject cooling water.



3. Stop under load or immediately after operation

When the wheel loader is shut down under load or immediately after operation, the cooling system stops working immediately and the heat dissipation capacity drops sharply. A large amount of heat generated by work accumulates near the heat source and cannot be dissipated in time, causing the cooling water of the cylinder head, cylinder liner, cylinder block and other heated parts to boil, causing the machine parts to overheat and ablate at high temperatures. At the same time, the engine oil attached to its surface will deteriorate, making it difficult to start the next time. In addition, if a diesel engine with a turbocharger is stopped suddenly, the temperature of the supercharger will rise to about 600°C, which may easily cause damage to the sealing ring. Therefore, the loader should unload the load before shutting down and run without load for 3 to 5 minutes, so that the machine temperature drops below 40°C and the water temperature drops below 50°C before it can be shut down.



4. Do not press the accelerator hard before stopping.

Many drivers mistakenly believe that pressing the accelerator before stopping can leave excess unburned diesel in the cylinder to facilitate the next start. In fact, this will cause incomplete combustion, black smoke, and increased carbon deposits; at the same time, slamming the accelerator a few times will suddenly increase the inertial force of the moving parts, exacerbating the wear of the moving pairs; secondly, unburned fuel will flow into the cylinder wall. The oil pan dilutes the engine oil and shortens the oil life cycle. Therefore, the correct operation is to run smoothly at medium and low speeds without load and then stop.



5. Slide into the shovel during shifting.

When the wheel loader is operating, many drivers are accustomed to changing gears while using the inertia of the machine's high-speed driving toward the material pile. After naturally decelerating, they then shift into gear and shovel the materials. Using the inertia of driving to rush towards the material pile will cause the whole machine to be violently impacted, causing uneven stress on each component, causing harm to the entire machine body. This will cause the bucket, boom, front frame, etc. to deform and crack; the transmission and clutch will be suddenly stressed, the torque will increase, and the friction plates will easily slip and become distorted; the transmission components will also be easily damaged. The correct operation is for the loader to put the transmission lever in low gear before shoveling, drive forward to the material pile at speed II, slowly insert into the material pile at speed I, and gradually increase the throttle for shoveling.