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The 1,400 kt/a delayed coking unit of Sinopec Luoyang Company was designed by Luoyang Petrochemical Engineering Company (LPEC), and its commissioning trial was successfully carried out in June 2008. The unit underwent its first major overhaul in September 2011, and the second major overhaul was carried out in October 2015. The delayed coking unit is an important secondary processing unit in the refining system of the Luoyang branch. As crude oil becomes heavier and contains more sulfur, the properties of the vacuum residue used as raw material for secondary processing are deteriorating; its sulfur content, salt content, and heavy metal content are increasing. Additionally, as the equipment reaches the later stages of its operational life, equipment failure problems in the coking unit become increasingly severe, thereby increasing the operational risks associated with this unit. This poses significant challenges to the safe operation of the unit as well as to its ability to operate over extended periods of time. To ensure the safe, stable, and long-term reliable operation of the coking unit, Luoyang Coking strengthens equipment management mainly from the following aspects. I. Strengthen professional management, improve equipment efficiency, and optimize key equipment. The delayed coking unit faces challenges such as changes in raw material properties, long operation cycles, altered production conditions, and adjustments to operation modes, which place higher demands on the equipment. To achieve intrinsic safety, the equipment must adapt to these new conditions. To address the issues that arise, measures such as research and development, technical improvements, and innovations are employed to ensure the safe operation of the unit. 1. Reform of the heating furnace burner: Use a low-nitrogen oxide seamless wall-mounted staged combustion burner. The 128 burners originally used in the heating furnace were RC-JH50 gas burners; the flames on both sides of the furnace tubes burned vertically upward, providing heating through dual-sided radiation. This arrangement made it easy for the flames to deviate and touch the tubes, resulting in uneven heat transfer and localized coking, which reduced the efficiency of the heating furnace. Currently, 128 sets of YX/BFQ-0.6 low-nitrogen oxide seamless wall-mounted staged burners are used; the cross-sectional view and combustion diagram of the burners are shown in Figure 1 and Figure 2 respectively. This type of burner utilizes hot-wall radiation technology, which prevents localized overheating and coking of the residue oil inside the tubes. As a result, the thermal resistance for heat transfer from the inner wall of the furnace tubes to the residue oil side is reduced, the overall heat transfer coefficient increases, thereby improving the efficiency of the heating furnace and extending the service life of the furnace tubes. 2. Modification of the mechanical seal for hot oil pumps: In a delayed coking unit, the stable operation of hot oil pumps is crucial. The fractionation system is the heart of the unit, so it is essential to improve the reliability of hot oil pump operation. The leakage problem of the thermal oil pump seal has consistently posed a challenge to the stable operation of the distillation unit equipment; after it came online, leakage from the thermal oil pump seal occurred frequently. In particular, the circulating oil pumps P1109A/B, the heavy paraffin oil pumps P1108A/B, the light paraffin oil pumps P1107A/B, and the bottom vent pump P1111A/B have a severe impact on the long-term safe operation of the delayed coking unit. Luoyang Coking has upgraded the mechanical seals of its hot oil pumps: the circulating oil pumps P1109A/B, the heavy paraffin oil pumps P1108A/B, the light paraffin oil pumps P1107A/B, the intermediate stage pumps P1106A/B, the bottom drain pump P1111A/B, and the oil throwing pump P1113A all use 32+52M type mechanical seals. The 32-system and 52-system are shown in Figures 3 and 4 respectively. The improvements to the auxiliary measures for the mechanical seal are as follows: (1) The mechanical seal has been changed from the original single 54 system to the advanced 32 (injected flushing) + 52 (unpressurized dual-seal system) ； (2) The 32-system is equipped with flow control valves, flow meters, thermometers, and pressure indicators; the original seal oil system did not have these, so it is now possible to monitor more effectively the seal oil injection in each hot oil pump ； (3) Operational improvements were also made to the coke powder carryover in the seal oil system by adding a seal oil filter to reduce the amount of coke powder contained in the seal oil. Since the mechanical seals of the 11 hot oil pumps at Luoyang Coking were upgraded to double-face mechanical seals, they have been operating smoothly to date, achieving the desired results. In particular, the implementation of auxiliary facilities for these mechanical seals has provided a solid physical foundation for their long-term, stable operation. ? 3. Replacement of the bottom cover machine: Luoyang Coking used the first-generation automatic bottom cover machine produced by Luoyang JianGuang. From the start of operation until 2011, over those three years, there were issues such as a high failure rate of hydraulic bolts; the open environment during coking led to significant environmental pollution; workers faced high labor demands when cleaning the sealing surfaces of the bottom cover machine, and the quality of sealing was directly related to the quality of cleaning, with human factors also playing a role. Especially in cases of abnormalities during the production process, such as the formation of pellet coke or the collapse of the coke layer during the water supply process, the limited lifting capacity due to the structural constraints of the equipment prevents the bottom cover from being opened in a timely manner. In emergency situations, manually removing the connectors of the flange on the bottom cover of the coke tower involves high risks, low efficiency, difficulty in control, a poor working environment, and high labor intensity. During the major maintenance in 2011, Luoyang Coking replaced the bottom cover mechanism for the coke tower by adopting a hydraulic pre-tensioned flat-valve type automatic bottom cover mechanism. The shapes of the two types of bottom cover machines are shown in Figures 5 and 6. Compared with previous bottom cover machines, these machines have the following advantages: (1) Their design takes into account special operating conditions such as difficulty in draining water, formation of coked particles, collapse of the coking layer, and coking of valve plates. They possess sufficient pulling and pushing forces, with a rated pulling force of 1040 KN and a maximum pushing force of 1280 KN, enabling them to meet even more demanding production conditions. (2) It features a variable sealing force design; during sealing, the total sealing force can reach 420 tons. When the cover is opened, the hydraulic bolts are used to reduce the total sealing force to 20–50 tons. This results in minimal wear of the valve plate and seat, thereby extending their service life. (3) The coking process is carried out in a hermetically sealed environment; there is no scattered coke on the floor nor any flow of coke water. The sealing surfaces do not require manual cleaning of coke, and the sealing performance is not affected by human factors. This results in lower labor intensity for workers and a better working environment. (4) The bottom cover machine system requires virtually no maintenance. Due to the change in environment during the decoking process, hydraulic bolts are not subjected to erosion by coke dust and decoking water, resulting in an **extended service life and a low failure rate. (5) The drive mechanism is designed with a 3-fold redundancy in driving force, and the driving force can be adjusted flexibly as needed to accommodate more complex operating conditions. (6) It has an interlock function with the coke tower sequential control system to prevent misoperations. 4. Improvements and optimizations of other equipment: In addition to the optimizations mentioned above, Luoyang Coking has also installed a safety interlock system for the coke towers, upgraded its water-based coke removal system, added an online pipeline corrosion monitoring system, optimized the automatic control system for air compressors, and implemented a remote water-based coke removal system, among other things. Since operations began, Luoyang Coking has continuously carried out technical optimizations and improvements to its equipment, addressing production challenges and safety issues at their root, thereby enhancing the operational efficiency of the facilities and improving production productivity. II. Achieving Efficiency through Precise Management: Implementing precise management in equipment management should be based on the safe operation of the equipment, with an emphasis on improving economic efficiency. Only by persistently applying precise management can the equipment operate safely and stably. The application of refined management is an important foundation for the proper and rational management of production facilities, and it is also a key element in advancing the modernization of corporate management. Actively explore and implement refined management to make the equipment management of installations standardized, systematic, scientific, and efficient. 1. Strengthen inspections to identify potential accident hazards early. Enhance inspection procedures, ensure high quality in these inspections, motivate operators to be more responsible, and detect potential accident hazards in advance to effectively prevent serious incidents from occurring. Luoyang Coking has ensured accurate and timely monitoring of pump vibration and temperature by installing new portable pump testing equipment and an online management system ； Launch the “You Shine, I Give Praise” campaign to reward those who identify potential accident hazards ； Increase the frequency of safety skills training and accident drills ； Urge maintenance units to improve the quality of equipment inspections. 2. Conduct equipment training to improve the operational skills of operators. The meticulous management of equipment actually involves managing people; it is crucial to enhance employees’ technical skills and their ability to maintain the equipment. Diverse training activities are carried out within daily management efforts, aiming to significantly improve the overall operational skills of employees at various levels and in different tiers. Operators are trained through technical analysis sessions, skill competitions, team-based training classes, youth training workshops, and by hiring team trainers. Emphasis is placed on carrying out the “Technical Analysis in Work Teams” initiative, with a different theme assigned each month; the topics cover aspects such as analysis of production abnormalities, process optimization, and accident handling, with all employees participating in discussions and learning. Technical managers provide feedback and rewards on the analysis results, and select the best ones for further promotion and learning. 3. Scientific management of equipment: Paying attention to equipment management, maximizing its efficiency, continuously improving its condition, and ensuring the proper operation of the facilities are the goals of scientific equipment management. Coking plants establish and implement post responsibility systems in equipment management to foster employees’ sense of responsibility for their duties. To further ensure the implementation of the system, the workshop conducts weekly inspections, issue reports, and carry out corrective actions regarding its implementation. The key aspects of equipment management in coking plants involve thorough maintenance, scientific management, and regular repairs. Make full use of the equipment information generated by the ERP enterprise management system, equipment management system, unit status monitoring system, pressure vessel and pressure pipeline management system, and pump inspection system to track the operating conditions of the equipment, thereby achieving scientific management of it. 4. Strengthen inspection, maintenance, and repair management. Doing so can extend the service life of equipment, eliminate potential hazards, ensure normal operation of the facilities, and improve work efficiency. For the maintenance of equipment and devices, daily upkeep, repair after incidents occur, repair following inspections, and planned preventive maintenance should be employed to ensure proper maintenance of the equipment. It is necessary to strengthen the assessment of equipment inspection and maintenance personnel by employing various evaluation methods, such as the \"Inspection and Safety Company Maintenance and Service Quality Evaluation Form\", the \"Inspection and Safety Company Repair Assessment\", and the \"Contractor Daily Supervision Assessment Form\", etc. Through these assessments, the repair capabilities and service quality of the inspection and maintenance units have been greatly improved. III. Implementation of various equipment competitions: The equipment competitions held must aim to ensure the safe, efficient, and stable operation of the equipment. They should be based on scientific and rational principles, with the goal of using such competitions to support equipment management. It is essential to ensure fairness, impartiality, and transparency in these competitions in order to motivate the operators. Effectively organize competitions that promote the safe and stable operation of equipment, competitions to solve production challenges, and competitions aimed at improving the efficiency of equipment. Currently, the competitions related to equipment management in Luoyang’s coking industry include: competitions on equipment stability, heating furnace competitions, evaluations of model responsibility areas and responsible pumps, as well as competitions for identifying potential hazards. Based on practical considerations, these competitions have strengthened the management of equipment infrastructure; they focus on providing special monitoring for key equipment, and they motivate operators to identify potential hazards. This helps to eliminate such hazards at an early stage, thereby ensuring the safe, stable, and efficient operation of the facilities. IV. Conclusions and Recommendations Equipment management requires the involvement of all staff: managers should oversee the equipment properly, operators should make good use of it, and maintenance personnel should repair it effectively. Equipment managers must strengthen equipment management and professional oversight, ensure the proper operation of critical equipment, adopt new technologies and devices, and improve the efficiency of the equipment. At the same time, it is necessary to strengthen refined management and equipment competition, seek efficiency through management and ensure stability, in order to guarantee the safe and stable operation of the installations. Based on the current operating conditions of Luoyang Coking, the following recommendations are made regarding equipment management: (1) Manage equipment operation dynamically. Due to raw material supply issues, Luoyang Coking operated at low or extremely low capacity from the second half of 2014 until the beginning of 2018; currently, its capacity is around 57%, with the heating furnaces operating in single chamber mode. Such significant and frequent fluctuations in production capacity inevitably have a substantial impact on the safe and stable operation of the heating furnaces, compressors, pumps, and heat exchangers. Therefore, it is necessary to implement dynamic equipment management tailored to different capacities and production conditions. (2) Make preparations for the major overhaul. During the three years of operation, the device revealed numerous equipment issues, and it was necessary to keep detailed records before carrying out major repairs ； Conduct research on other advanced delayed coking units, enhance communication, and propose effective maintenance projects ； Operators are encouraged to submit more suggestions for maintenance in order to address production challenges and ensure the long-term safe operation of the equipment. (4) In 2018, the proportion of asphaltene plus slurry in the feedstock used by the coking unit continued to increase, reaching as high as 44%; the sulfur content in the feedstock was as high as 2.8%. Severe coking and corrosion occurred in some of the unit’s equipment, posing new challenges to their operation and maintenance, which require close attention.