Causes and improvement measures of serious wear of hydraulic gear pumps in China
Severe wear of the hydraulic pump of the excavator has a fatal effect on the excavator, so such problems must be solved in time for the excavator. When repairing the hydraulic pump of the excavator, find the cause of the fault from the following three points:
(1) Check the internal leakage of the boom cylinder
The simple way to do this is to raise the boom to see if it has a noticeable free fall. If the drop is obvious, disassemble the cylinder for inspection, and replace the sealing ring if it has been worn.
(2) Check the control valve
FIRST CLEAN THE SAFETY VALVE, CHECK WHETHER THE VALVE CORE IS STILL UNCHANGED, AND THEN CHECK THE WEAR OF THE CONTROL VALVE CORE, ITS CLEARANCE USE LIMIT IS GENERALLY 0.06MM, AND THE WEAR SHOULD BE REPLACED.
(3) Measure the pressure of the hydraulic pump
If the pressure is low, it is adjusted, and the pressure still cannot be adjusted, which indicates that the hydraulic pump is seriously worn.
First, the main reasons why the boom load cannot be lifted are:
1. The hydraulic pump of the excavator is seriously worn
Serious leakage in the pump when running at low speed; At high speed, the pump pressure increases slightly, but due to the wear and internal leakage of the gear oil pump, the volumetric efficiency decreases significantly, and it is difficult to reach the rated pressure. The long-term work of the hydraulic pump aggravates the wear, the oil temperature rises, resulting in the wear of hydraulic components and the aging and damage of the seals, the loss of sealing ability, the deterioration of the hydraulic oil, and finally the occurrence of failure.
2. The selection of hydraulic components is unreasonable
The boom cylinder specification is 70/40 non-standard series, and the seals are also non-standard parts, which is expensive to manufacture and inconvenient to replace seals. The small bore of the boom cylinder is bound to make the system set pressure high.
3. The hydraulic system design is unreasonable
The control valve and the full hydraulic steering gear are connected in series with a single pump, the safety valve is set to 16MPA, and the rated working pressure of the hydraulic pump is also 16MPA. The hydraulic pump often works under full load or long-term overload (high pressure), and the system has hydraulic impact, long-term oil change, hydraulic oil is contaminated, aggravate the wear of the hydraulic pump, so that the hydraulic pump casing bursts (such failures were later discovered).
2. Improvement and effect
(1) Improve hydraulic system design
After many demonstrations, the advanced priority valve and load sensing full hydraulic steering gear form was finally adopted. The new system can prioritize the distribution of flow to it according to the steering requirements, regardless of the size of the load, the speed of the steering wheel can ensure sufficient oil supply, and the remaining part can be fully supplied to the working device circuit, thereby eliminating the power loss caused by excessive oil supply to the steering circuit, improving the system efficiency and reducing the working pressure of the hydraulic pump. Reduce severe wear of excavator hydraulic pumps.
(2) Optimize the design of boom cylinder and hydraulic gear pump shape
Reduce system operating pressure. Through optimized calculations, the boom cylinder adopts the standard series 80/4. THE DISPLACEMENT OF THE HYDRAULIC PUMP IS INCREASED FROM 10ML/R TO 14ML/R, AND THE SYSTEM SETTING PRESSURE IS 14MPA, WHICH MEETS THE LIFTING FORCE AND SPEED REQUIREMENTS OF THE BOOM CYLINDER.
(3) Strengthen daily inspection and maintenance
During use, we should also pay attention to the correct use and maintenance of the loader, regularly add or replace hydraulic oil, maintain the cleanliness of hydraulic oil, and strengthen daily inspection and maintenance. In this way, serious wear of the hydraulic pump of the excavator can be avoided.
At the beginning of the new year, Vientiane is renewed. At 7:58 on January 28, 2023, Shao Nihua, secretary of the party committee and chairman of the board, and Li Yuqiang, general manager, took the lead in igniting the New Year "opening cannon" of the pump company. With the roar of firecrackers, the pump company ushered in a new year, a new starting point, and a new hope. After the end of the "door opening gun", the company's leadership team went to various departments and production workshops to greet the New Year, cheering everyone and sending sincere greetings and New Year wishes. "Happy New Year! New Year's greetings to everyone! "Everywhere they went, members of the company's leadership team shook hands and talked with everyone, sending New Year wishes and the first rays of joy and warmth of the New Year.
In the afternoon of June 29, 2022, Wu Weiping, deputy director of Shenyang Economic and Technological Development Zone Management Committee, and his party visited the company to investigate the operation of the enterprise and held a discussion meeting. Li Yuqiang, general manager of Zhongshang Pump Industry, and other company leaders attended the discussion. The relevant persons in charge of business department, science and innovation department, industry and information bureau, financial bureau and Minsheng Bank accompanied the research.
1. Recruitment positions and number of positions 1 Vice Minister of Quality, Safety and Environmental Protection 2. Job responsibilities 1. Familiar with national and local guidelines, policies, laws and regulations, standards and systems related to environmental protection, occupational health and safety production. Assist the minister in environmental protection, occupational health and safety production, reduce and avoid risks, prevent accidents, and ensure the safe and smooth operation of the company's production and operation. 2. Assist the minister in establishing and improving the management system and workflow of environmental protection and energy conservation, occupational health, safety production and energy conservation and emission reduction, and assist the minister in the preparation, publicity, implementation and revision of the system process. 3. Assist the minister in organizing safety production inspections, special inspections, special supervision, safety production emergency plans, safety drills, etc., and conduct safety inspections of hazard sources, key areas and accident-prone places from time to time. Assist the minister in the investigation, analysis, summary and accountability of the company's extraordinarily large, major, large and general production safety accidents, and do a good job in handling accidents and work injuries.