The Handan Iron and Steel CSP continuous casting machine is a complete set of technology and key equipment introduced from Germany by Handan Iron and Steel Group, which was put into production and operation at the end of 1999. Its single machine production capacity is 1.2 million tons of thin slab, and it is a production equipment with world advanced level.  
This production line is a highly automated production line, and most of its equipment uses hydraulic control technology to achieve various control actions. Its mechanical equipment widely adopts centralized lubrication and thin oil lubrication; Therefore, whether the hydraulic lubrication system can be managed and maintained well is directly related to the integrity of the equipment and the smooth progress of production. In the more than 4 years since its trial operation, the production line has gone from frequent failures during the trial production period to several consecutive months without any failures. The oil consumption has increased from a dozen barrels per month at the beginning to less than 5 barrels per month now, and the hydraulic lubrication system of this production line has entered a good operating state. Based on our maintenance and management experience over the past few years, we have mainly carried out the following tasks.  
1. Starting from small details, do a good job in equipment maintenance
1) Starting from the governance of leakage, enhance equipment reliability. Leakage is a common phenomenon in some metallurgical enterprises, but for hydraulic systems, the harm of just a small leak cannot be estimated. The hazards of hydraulic leakage cannot be ignored, as it damages the environment, damages equipment, increases costs, endangers the safety of operators, and affects production. Therefore, we firmly prevent any leakage or seepage.  
Starting from the quality of sealing spare parts, select high-quality sealing components to ensure their reliable and durable quality; Corresponding seal replacement cycles have been developed for different environmental temperatures, and seals are regularly replaced.  
Revamp the site and modify the parts of the pipeline that are prone to leakage to reduce the occurrence of sudden accidents.  
Optimize the oil pressure and oil tank temperature of the hydraulic lubrication system. Temperature and pressure have a significant impact on the sealing of the system. The higher the temperature and pressure, the more likely the seals are to age. According to the actual needs on site, we adjust the system pressure that does not require high pressure to an appropriate value to reduce energy waste; Adjust the oil temperature of the hydraulic lubrication system's oil tank from the design value of 45 ℃~55 ℃ to 37 ℃~45 ℃, so that each hydraulic lubrication system is in good working condition.  
Reduce vibration. Vibration can easily cause loose joints and bolts, leading to leakage. The vibration of hydraulic pumps and motors can damage them. Regularly check the coaxiality of the pump and motor, ensure that all bolts and joints are securely fastened, and ensure proper pipeline fixation and shock resistance. Keep the oil level in the tank above 2/3 and strictly follow the maintenance procedures during maintenance. Check the nitrogen pressure of the accumulator every 3 months to ensure that the accumulator is in good condition, reduce system pressure shock, and eliminate vibration.  
2) Ensure the cleanliness of the oil. For hydraulic systems, oil is like human blood. When mixed with other impurities, it can cause great harm. According to relevant data statistics, 60% of hydraulic system failures are caused by oil contamination. Only by keeping the oil clean can the equipment operate normally.  
① Two aspects of oil contamination:
Internal pollutants, such as unclean hydraulic components and unclean oil itself during initial use of the system; Wear of oil components during system operation; Wear of bearings, gears, and other components in the lubrication system, as well as oxidation and deterioration of oil or grease;  
External pollutants, such as dust in the air invading the fuel tank; Contaminants brought in during maintenance and replacement of spare parts.  
② Countermeasures for the causes of oil pollution:
When adding new oil to the system, it must be filtered through an oil filter cart before being added, and different oil products should use their own refueling carts. If adjustment is needed, it must be cleaned before use;  
When replacing new components or parts, it is necessary to first replace the connection parts of the components or parts, and then replace them with clean new spare parts;  
Regularly replace the circulation filter and air filter of the system;  
Strictly follow the "Maintenance Regulations" for maintenance and repair, use clean tools during maintenance, and keep hands clean;  
Strictly manage spare parts, store them in a pollution-free place, and pay attention to keeping them clean;  
Regularly conduct oil inspection and testing.  
2. Attach great importance to the inspection of oil products
1) The inspection of oil products can provide the cleanliness level of the oil itself, keep good equipment records, and ensure the normal operation of hydraulic lubrication equipment. By analyzing the elements of the oil, one can grasp the operating status of the equipment and understand its condition. For example, after the oil analysis in December 2000, it was found that the copper content in the clutch hydraulic station oil exceeded the standard severely. Combined with the operation of the equipment at that time, it was inferred that the swing reduction clutch was severely worn. Therefore, the swing reduction clutch was inspected and found to have excessive clearance between the worn plates, requiring maintenance. Therefore, the swing reduction clutch was replaced to avoid a sudden equipment accident.  
2) According to the results of regular oil analysis, the oil should be changed regularly based on its quality. According to the maintenance manual provided by the foreign party, the oil in the hydraulic lubrication system needs to be replaced regularly. Due to the different operating conditions of various hydraulic lubrication systems, the quality changes of oil products are also different. Regular oil changes often result in some oil with good quality being replaced, leading to significant waste; The oil has already deteriorated, but it has not been replaced due to its expiration date, resulting in component damage or poor lubrication of the equipment.  
3. Strengthen equipment basic management
1) Write the "Operation, Maintenance, and Overhaul Regulations for Hydraulic Lubrication Equipment" and organize learning and training. Only personnel who pass the assessment can take up their posts. Based on the improvement of actual production requirements and on-site modifications, continuously improve the regulations to enhance their guidance, scientificity, and operability.  
2) Combined with the packaging mechanism of the equipment, strengthen the inspection and maintenance of the equipment. Inspection and maintenance are the foundation of equipment maintenance and repair. Through inspection, problems in equipment operation can be detected early, and faults can be eliminated in the bud to ensure good equipment operation.  
3) Do a good job in equipment recording. Equipment recording is the basis for us to carry out equipment work. We carefully record equipment operation, equipment inspection, and equipment maintenance, and make full use of these records to develop spare parts and material declaration plans, search for the occurrence rules of hydraulic lubrication system failures, determine and optimize the replacement cycle of seals and vulnerable parts, and thus develop corresponding regular maintenance projects to reduce sudden equipment failures.  
4. Technological innovation and continuous improvement
With the improvement of equipment maintenance level, deficiencies in the installation and design of hydraulic lubrication equipment are discovered and modified to make the system more reasonable and perfect. No design and installation can be perfect, there are always some shortcomings. With the improvement of equipment maintenance level, we will promptly rectify the shortcomings found and discover the benefits of improvement. For example, we have improved the dry oil pipeline in the continuous casting straightening machine area to avoid the defect of bearing burnout caused by insufficient oil supply to some straightening machine roller bearings; The hydraulic pipeline in the swing reduction area has been modified to solve the problem of easy failure and difficult maintenance; Improved the holding pressure of the swing pressure reducing roller control circuit, solving the problem of the roller disengaging from the high position; In the renovation of the dry oil system, we localized most of the spare parts in the system and modified the control system by replacing the original limit detection with low-pressure detection, solving the problem of inaccurate dry oil empty limit detection and improving the operation of the dry oil filling system. In the nearly 5 years since production, we have made as many as 40 improvements to the site, reducing unexpected accidents and facilitating on-site maintenance, greatly promoting production and creating benefits for Handan Iron and Steel.  
5. Conclusion
Thanks to the unremitting efforts of our hydraulic technicians and maintenance workers, the hydraulic lubrication system of the CSP continuous casting machine has been operating at a low failure rate for the past two years, with a failure rate close to zero, laying a solid foundation for the high yield and efficiency of the CSP production line at Handan Iron and Steel.