Hydraulic system maintenance and maintenance technology

1. Failure and risk in mechanical hydraulic system

In terms of stress. Due to the failure of some devices, the hydraulic system will have pressure instability during mechanical work, and the pressure will be abnormal when the pressure is measured at the pressure point, and the pressure will exceed the normal range value. Due to the instability of the pressure, the equipment will not meet the accurate requirements during operation. Serious can make the construction machinery can not operate normally, delay the construction period.

Working medium. Due to improper operation of personnel or other reasons will cause the pollution of hydraulic oil, so that the hydraulic oil function is reduced, or even does not work. The main factors that pollute hydraulic oil include: (1) the hydraulic oil itself deteriorates and its physical properties change. For example, when the system oil temperature is too high, some functions of the hydraulic oil are lost, and the parts cannot reach the previous accuracy in the case of heat, and the efficiency is reduced; (2) The hydraulic equipment is mixed with granular solids such as sand and soil, polluting the tank. (3) When the tightness of the hydraulic system is destroyed, the leakage of hydraulic oil will also increase the wear of mechanical parts. In addition, if the tightness of the hydraulic system is not good, the air with moisture will enter and affect the work of the hydraulic oil, which will cause resistance to the power conversion and output.

In terms of speed. With the increase of the use time of the machine, the overall system will slow down, and the final energy will be lost during the operation, resulting in the stagnation of the machine. Therefore, it is necessary to find the cause in time to avoid delay in construction and extend the service life of the equipment. The speed of the actuator should be tested on time to see whether it is within the normal range value, so as to further detect the abnormal part. In addition, it is also necessary to check whether the equipment is worn, especially the wear of the hydraulic cylinder, which can make the outside air enter, resulting in changes in the viscosity of the hydraulic oil, and then affect the mechanical working speed.

Abnormal sound aspect. When the machinery is working, the hydraulic system has an abnormal sound, the greater the abnormal sound, the greater the vibration degree of the equipment caused, and the more prominent the safety risks. Serious abnormal noise will cause the stability of mechanical operation to decrease, delay the project.

Parameter setting and installation. If the wiring is incorrect during the installation of the hydraulic system, the system may be short-circuited and the equipment may be damaged. After the installation, the parameter setting is also very important, the wrong parameter will cause the machine can not trigger the action or can not reach the required action standard degree. Some parts of the hydraulic system will be damaged if the parameter setting of the standard unit is exceeded seriously.

Wire contact. The failure of wire contact refers to: when the wire is virtual, the system is in the case of low voltage, the hydraulic system is difficult to start, which will lead to the equipment is difficult to operate normally, and when the voltage is zero, it will cause the operating equipment to trip and the mechanical equipment to stop moving.

2, maintenance and maintenance technology application

(1) Prevent the entry of impurities, water and air. Due to the complex composition of the internal components of the hydraulic system, and more precision parts, if there are granular solids into the internal hydraulic system, it may be included in the gaps of each part, which will inevitably cause damage to the parts, and may also block the oil pipe, thus affecting the mechanical hydraulic system. Therefore, when adding hydraulic oil, it is necessary to fill the filter to prevent particles from entering the system with hydraulic oil, and when the equipment is maintained and inspected, the exposed part should be cleaned and wiped before being disassembled to avoid dust taking the opportunity to enter the system.

In addition, the staff should also pay attention to the cleaning of working clothing to ensure the cleanliness of the operating environment. In addition, the hydraulic oil has a lubricating effect, the lubrication performance of the hydraulic oil mixed with water is low, the wear speed of the parts is accelerated, and the entry of water reduces the quality of the hydraulic oil, which will seriously corrode the iron metal inside the hydraulic system. Therefore, maintenance personnel should pay attention to check often to see whether the hydraulic system is sealed, do not expose hydraulic oil in a place with large moisture, reduce the chance of contact between oil and water, if the hydraulic oil has a large moisture content, it should be filtered to ensure that it can be used within the standard range.

(2) The selection and use of hydraulic oil. Hydraulic oil is the soul of the entire hydraulic system, hydraulic oil if there is a problem will affect the operation of the entire hydraulic system, so the choice of correct and reasonable hydraulic oil is very necessary. The structure of mechanical hydraulic systems in different fields is different, so the model of hydraulic oil is not the same. It is necessary to carefully choose the hydraulic oil products sold in the market for the model of the machine and the instructions for the use of the machine, and try not to replace them easily after selecting the model and brand. After choosing the appropriate brand and model of oil, we also need to pay attention to the following points during use:

1) First check whether the physical properties of the hydraulic oil have changed, mainly the change of color and taste, to see whether the color becomes dark brown or milky, if the color changes that the oil has deteriorated, can not be added to the tank, need to replace the new oil, and if the hydraulic oil has a harsh odor, it also indicates that the oil has deteriorated, need to stop using.

2) When adding hydraulic oil, it is necessary to filter first to filter out impurities and improve the purity and quality of hydraulic oil.

3) Pay attention to the cleanliness of the operating environment when carrying out equipment maintenance, and try to ensure that there is no dust in the air. In addition, if the parts need to be removed when checking and maintaining the equipment, the exposed parts should be cleaned and wiped first to ensure that no impurities fall into the hydraulic system during the removal process.

4) During the operation of the hydraulic system, attention should be paid to controlling the oil temperature. In the case of high temperature, the fluidity of the hydraulic oil will become higher and the viscosity will decrease. In this case, it is possible to lead to leakage of the hydraulic closure system, resulting in a series of failure problems including equipment oxidation.

Improve practice.

1) During the operation, the operator should not operate the equipment rudely under any circumstances, and should operate the equipment in a peaceful manner and maintain good operating habits. This alone, if done, will greatly reduce the probability of equipment problems.

2) During the normal operation parameter setting, the parameter cannot be set at the threshold limit point of the range to reduce the loss of the equipment.

3) In the process of using the hydraulic system, the operator should learn to judge a variety of common problems and solve them in time. Usually, subjective judgment is used to diagnose and analyze the faults of mechanical hydraulic systems in a comprehensive manner by combining the information from the eyes, ears, hands, noses and other senses. Therefore, staff are required to be familiar with common faults and solutions, accumulate experience and summarize mistakes and lessons according to the actual situation. For example: when the equipment is running, pay attention to whether there is an abnormal sound, if there is an abnormal sound, first determine where the abnormal sound is coming from, and then determine the cause of the abnormal sound. If the problem cannot be solved in time, it is necessary to stop the mechanical operation in time to solve the problem, and then restart the mechanical operation after solving the problem. Similarly, the pressure and temperature of the hydraulic system are places that need to be paid attention to in the operation of the entire mechanical equipment, and problems should be found and solved in time.