How does the hydraulic system, the

date:2026-01-26

The hydraulic system of a dump truck is like the human heart and muscles, which is the core of its "flexibility and stretch" and efficient unloading. Once the system fails, the entire vehicle will be "paralyzed". Today, we use the most understandable way to thoroughly explain its working principle and golden rules of maintenance.

1. Working Principle: How does the hydraulic system "lift the stone"?

There are four core items, none of which can be missing.

Imagine a hydraulic system as a closed "force transfer system":

Heart: Hydraulic oil pump - driven by the power take-off, converts mechanical energy into hydraulic energy to generate high-pressure oil flow.

Blood: Hydraulic oil - the medium that transmits power and is also responsible for lubrication and cooling.

Muscle: Lifting cylinder (commonly known as "jacking") - receives high-pressure oil, pushes the piston rod to extend, and directly lifts the cargo box.

Brain: Hydraulic valve group (multi-way valve, limit valve, etc.) - controls the flow direction, pressure and flow of oil, and commands when the "top" starts, stops, and falls.

Work flow (a complete lift and landing)

Let's follow the path of the hydraulic oil and look at the complete cycle:

Key point: When landing, the cargo box is pressed back into the oil cylinder by its own weight, and the oil just flows back into the tank. Therefore, it is strictly prohibited to drive forcefully on inclined roads or in a lifted state, otherwise serious accidents may occur due to imbalance of oil pressure.

Maintenance Guide: Remember the "3+3 Golden Rule" to reduce the failure rate by 80%

Hydraulic oil "three levels" are strictly controlled

1. Choose the right oil: Strictly follow the brands recommended by the manufacturer (such as anti-wear hydraulic oil HM-46, etc.). Do not mix different brands and models.

2. Keep it clean: Make sure the refueling port is clean before refueling; refueling tools must be dedicated and clean; the fuel tank cap must be tightened.

3. Regular replacement: The first maintenance is recommended at 2000-3000 kilometers or 500 working hours, and then every 10,000 kilometers or once a year. If the working environment is harsh (dusty, high temperature), the cycle needs to be shortened.

"Three Prohibitions" for Daily Operations

1. Overloading and unbalanced loading are prohibited: Overloading is the "number one killer" of the hydraulic system. Unbalanced loading will cause uneven stress on the cylinder, which can easily lead to deformation and oil seal damage.

2. Lifting and driving and slamming to the ground are prohibited: When driving, you must make sure that the cargo box is completely in place and locked. After unloading, the cargo should be landed smoothly. Do not quickly drop the cargo with one click while in the lifted state. Huge impact will directly damage the cylinder, frame and valves.

3. It is forbidden to "hold the pressure" for a long time: after the cargo box is lifted to the top, the system will automatically unload (the sound of the oil pump will change). At this time, the lifting operation should be stopped in time. Continued "holding" will cause the oil temperature to rise sharply and damage the oil pump and seals.

Regularly inspect the "three key points"

1. Check for leaks: Before leaving the vehicle every day, go around the vehicle to check whether there are any oil stains on the cylinder piston rod, each oil pipe joint, and the valve block interface. Even minor leaks should be addressed immediately.

2. Listen for abnormal noises and smells: When working, pay attention to whether the oil pump has abnormal noises and whether there are abnormal noises in the cylinder; smell whether there is a smell of burning rubber (caused by overheating).

3. Observe the status: Observe whether the lifting and descending speeds are significantly slower, whether there is jitter or weakness. This is often a sign of oil pump wear, cylinder leakage or oil line blockage.

Treat your hydraulic system well and it will give you efficient and reliable feedback. Remember - "three points of repair, seven points of maintenance", the core of maintenance lies in clean oil, standardized operation and diligent inspection.