Cause Analysis and Solution of High Oil Temperature Failure of Hydraulic System（3）

Cause Analysis and Solution of High Oil Temperature Failure of Hydraulic System（3）

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Causes of high oil temperature caused by pump valves and countermeasures

      If the pump is installed and used correctly, the hydraulic pump can be used continuously for many years without maintenance. Once the problem is discovered, the cause should be found out and eliminated as soon as possible. With the help of hydraulic diagrams to diagnose the system's faults, the work is much simpler. The hydraulic valve is manufactured with high precision. As long as it is properly assembled and maintained in good working condition, there is generally little leakage, and the oil pressure, direction and flow rate in the system can be accurately controlled. Contaminants in the oil are the main cause of valve failure. A small amount of fiber, dirt, oxide or sludge can cause failure or damage to the valve. If products from a trusted manufacturer are used, the possibility of improper design is very small. The main reasons for the failure of pumps and valves are as follows:

1. External conditions

1.1 Loose fastening bolts, deformation and damage caused by excessive fastening.

1.2 Dramatic changes in load.

1.3 Vibration and shock.

1.4 Assembly, disassembly, repair work and sequence errors, the quality of tools, damage, deformation, scars and loss of parts.

1.5 Deformation and damage caused by twisting of piping, or piping errors, etc.

2. Hydraulic oil conditions

2.1 Mixed with impurities, water, air and deterioration.

2.2 Whether the viscosity and temperature are appropriate.

2.3 Lubricity.

2.4 Whether the inhalation conditions are good (to prevent cavitation, excessive positive pressure or negative pressure).

2.5 Abnormal high pressure and pressure fluctuation.

 

3. The quality of the component itself

3.1 Structure and strength.

3.2 Quality of parts (bearings, oil seals, bolts, shafts).

3.3

Wear, scratches, and stickiness of sliding parts.

3.4 Wear, scratches, deformation and deterioration of parts.

3.5 Oil leakage (internal leakage, external leakage).

 

In order to make valve maintenance work safe and reliable, the following principles should be followed:

 1. Cut off the power before disassembling the hydraulic valve to avoid accidental startup of the system or flying out of the tool.

2. Before disassembling the hydraulic valve, move the handle of the valve in all directions to release the pressure in the system.

3. Before disassembling the hydraulic valve, all working mechanisms of the hydraulic transmission should be locked or placed in a lower position

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     Cause analysis and countermeasures of high oil temperature caused by accumulator

       The accumulator is a device for storing high-pressure oil. When the pump is in a normal no-load state or idling state, the accumulator can be filled with oil. The high-pressure oil stored in the accumulator can be released when needed to supplement the flow of the pump, or supply oil to the system when the pump is stopped. Most of the accumulators we currently use are diaphragm and bladder types; accumulators rely on compressed inert gas to store energy, usually nitrogen, and the actual inflation pressure cannot be higher than the critical value. In most cases, the inflation pressure value should be the highest in the system The pressure value is within the range of 1/3 to 1/2, so that the effect is best, and the working characteristics of the circuit rarely change. It is particularly emphasized that do not use oxygen or oxygen-containing mixed gas.

 

        In short, through a more in-depth understanding and mastery of the hydraulic system, and continuous improvement of technology and work ability, can we better solve the main problems faced by hydraulic equipment users and manage the hydraulic system. When there is a problem in the system, the real cause of the system failure can be found. More work starts from the usual daily inspection, paying attention to the details of equipment inspection and maintenance work, and eliminating various factors that cause the failure in the early stage of the failure. Through continuous improvement and improvement of the working cycle, the predictive maintenance work can be further improved in the constantly changing working environment, ensuring that the equipment can exert greater benefits and achieving the goal of zero equipment accidents.