2024 “China Health Monthly” Issue No. 6

The stripping and bleaching workshop is holding an on-site training session.

On June 17, 2024, Wang Zhong convened all logistics personnel for an on-site training session in the bleaching workshop of the North Factory. The purpose of this session was to address and eliminate quality issues such as yellow spots in our products by tracing their root causes. During the session, Wang Zhong explained to the employees the operational principles and process flow of the bleaching machinery and equipment, enabling them to gain a direct understanding of the raw material production process and enhancing their clarity about the company’s raw-material handling procedures. Throughout the training, Wang Zhong, along with Yu Guozhi, the head of the bleaching workshop, and Zeng Yanwen, an experienced veteran from the quality control department, leveraged their many years of industry experience to analyze and explain the causes of the yellow spots. They also assigned specific personnel to develop and implement appropriate corrective measures based on the analysis conducted during the training session and to verify the effectiveness of these measures. Resolving this quality issue will significantly reduce the company’s customer complaints, restoring customers’ confidence in Zhongjian Company. At the same time, we must continue to make relentless efforts in addressing other quality challenges as well. “Heaven rewards those who work diligently—perseverance is key.” By facing and solving problems, we can continually improve our products and earn the recognition and trust of our customers.

Training session scene at the bleaching workshop

Organize employees to share their personal learning insights.

County-level Party member leading cadres came to visit the company’s Party building base.

Visit the company’s Party building base.

A brief overview of the company’s development history.

Introducing the members of the Friendship Home established by the industrial park.

Learn about the directory of enterprises in the industrial park.

View products from selected enterprises in the industrial park.

Share each other's thoughts and feelings.

Participate in the county government’s drug prevention and awareness campaign.

Equipment Preventive Maintenance Strategy and Its Effectiveness Evaluation

I. The Importance of Equipment Maintenance

Equipment maintenance, also known as equipment repair, refers to the technical activities aimed at restoring malfunctioning equipment to normal operation through a series of procedures. These activities encompass both planned and unplanned repairs for various types of failures and accidents. The fundamental components of equipment maintenance include equipment upkeep, inspection, and repair. The quality of maintenance directly influences the service life of equipment. Equipment inspections enable timely detection of emerging problems, allowing them to be resolved as quickly as possible. Equipment repair is an essential means of restoring damaged equipment to its original functional state. Tools are indicators of a society's level of advancement; equipment, as the primary tool of enterprise production, plays a crucial role in shaping the development of businesses. In an era of rapid technological progress, traditional equipment is undergoing a transformation toward greater precision and automation, resulting in ever-increasing production efficiency and increasingly sophisticated machinery. At the same time, enterprises are gradually expanding in scale, placing ever-higher demands on production output and quality. The trend toward technology-intensive operations is becoming increasingly pronounced. However, achieving these goals all depends on the impetus provided by advanced equipment.

Equipment maintenance keeps equipment in good working condition, thereby ensuring the continuity of enterprise production and enabling the company to continuously generate profits.

II. The Concept and Strategies of Preventive Maintenance

Preventive maintenance refers to the systematic, periodic inspection or replacement of parts performed on equipment before any failures occur. The goal is to ensure that the equipment remains in optimal working condition at all times, thereby preventing potential hazards and guaranteeing uninterrupted production and smooth business operations. By implementing preventive maintenance, equipment utilization can be significantly improved, the risk factor can be minimized, and prolonged production downtime caused by equipment failures can be avoided. A maintenance strategy is the optimal approach and set of standards for maintaining equipment, taking into account a wide range of comprehensive factors. Through various maintenance methods and appropriate maintenance frequencies, it aims to keep equipment in its best working condition while minimizing costs and maximizing safety. The main components of a maintenance strategy include selecting the appropriate maintenance method and determining the optimal maintenance cycle. 1. Classification of Maintenance Methods Maintenance methods can be categorized into five types according to their timing: corrective maintenance (reactive), preventive maintenance, predictive maintenance, condition-based maintenance, and maintenance-free design. In practice, most modern equipment does not rely on just one single maintenance method; rather, they integrate multiple approaches.

2. Selection of Maintenance Approaches: When deciding which maintenance approach is best for equipment repair, the following criteria should be considered: First, equipment-specific factors—primarily, selecting the most appropriate maintenance approach based on the specific nature of the equipment’s failure. Second, economic factors—choosing a maintenance approach that ensures the lowest possible repair costs while keeping the equipment in optimal condition. Third, safety considerations—safety comes first, making it the most important and primary factor to take into account when selecting a maintenance approach. Specific methods for choosing a maintenance approach are as follows: First, identify the items that require maintenance. Not every industrial equipment needs preventive maintenance; rather, the decision on whether and when to perform preventive maintenance should be based on the equipment’s value, its role in the company’s production process, as well as factors such as safety and cost-effectiveness, to determine the priority order for preventive maintenance and the specific parts to be used during repairs. Second, identify the specific type of failure based on the failure mode, and then select the appropriate maintenance approach according to the recommendations for that particular mode. Third, propose targeted preventive measures. Based on the analysis above, we can roughly determine which equipment needs maintenance, clearly identify the types of failures and their corresponding solutions, and pinpoint the most suitable maintenance measures.

III. Issues in Preventive Maintenance

Analysis reveals that in specific maintenance decision-making processes, the lack of a systematic maintenance theory and a rational effectiveness evaluation system has led to certain aspects of preventive maintenance for industrial equipment that still require further improvement. 1. Inappropriate selection of maintenance methods results in increased workload. Due to incomplete analysis of failures, the chosen maintenance methods are often unsuitable, leading to delayed or incorrect resolution of faults. This not only wastes time but also disrupts production. As a result, the failure to identify an appropriate approach significantly increases the workload associated with maintenance tasks. 2. Implementation of preventive maintenance plans proves ineffective, and maintenance costs remain high. Given today’s advanced equipment performance and complex structures, it is increasingly difficult to promptly identify and address faults. Maintenance personnel often rely solely on subjective guesswork and trial-and-error approaches. In the process, they must repair or replace parts or components they suspect might be problematic—this not only consumes considerable time in exploration but also incurs substantial financial costs when replacing parts with new ones. 3. Preventive maintenance requires a practical and effective evaluation system. The effectiveness of preventive equipment maintenance serves as a crucial indicator for assessing whether maintenance efforts are truly working. Maintenance itself is merely a process; the real outcome lies in its effectiveness. The ultimate goal of maintenance is to ensure that equipment operates in optimal conditions. Therefore, evaluating maintenance effectiveness not only provides guidance on how to carry out maintenance but also allows us to assess how well the maintenance efforts have actually performed.

IV. Equipment Preventive Maintenance Strategy and Its Effectiveness Evaluation

The proper evaluation of preventive maintenance effectiveness serves as an indicator for preventive maintenance strategies. However, in practice, it is extremely difficult to determine the exact maintenance cycle. Previously existing mechanisms for evaluating maintenance effectiveness have all assumed that the parameters characterizing maintenance effectiveness are deterministic—fixed values under constant conditions—and thus fail to accurately reflect real-world situations. By analyzing actual maintenance practices, we can see that the effectiveness of maintenance is not fixed; rather, it fluctuates within a normal range of values and can be regarded as a random variable. Therefore, the parameters used in preventive effectiveness evaluations should be treated as uniformly distributed random variables. Based on this theoretical framework, we can develop appropriate mathematical models to evaluate preventive maintenance effectiveness. The optimization model for average maintenance costs per unit time treats the parameters of preventive maintenance effectiveness as uniformly distributed random variables. Its fundamental assumptions include: the probability of equipment failure when no maintenance is performed; the effectiveness of preventive maintenance at regular intervals; the change in preventive maintenance parameters after minor repairs conducted at fixed preventive maintenance intervals; and, after a certain period of sustained preventive maintenance, the decision to replace the equipment when its failure rate is minimized, followed by statistical analysis of maintenance costs. By constructing a mathematical model based on these theoretical assumptions and conducting subsequent analysis, we can determine that both the maintenance cycle and the frequency of maintenance significantly influence maintenance costs. When specific numerical values are substituted into the model, it becomes clear that treating preventive maintenance parameters as uniformly distributed random variables better reflects real-world conditions than assuming them to be fixed values. The former approach effectively reduces the average maintenance cost per unit time and is also more practical and operational. Most importantly, it provides an effective and rational reference standard for preventive maintenance planning.

The operation of an enterprise requires production tools, and among these, equipment is the most critical. For equipment to function properly, it must experience as few malfunctions as possible. Maintenance is the means by which we ensure that equipment operates smoothly. Equipment maintenance not only demands substantial financial resources but also leads to reduced corporate profits due to production downtime—and when you add in maintenance costs themselves, the overall expenditure can become quite significant. However, preventive maintenance can address these shortcomings: rather than waiting until equipment breaks down before repairing it, preventive maintenance involves regularly inspecting equipment or replacing parts on a scheduled basis. This approach enables us to promptly eliminate potential safety hazards. Despite its advantages, preventive maintenance for equipment still has certain limitations, underscoring the need for improved strategies to ensure effective implementation, minimize maintenance costs, and achieve optimal results. By analyzing traditional evaluation models for the effectiveness of preventive equipment maintenance and taking into account actual conditions, we propose a new evaluation model for maintenance effectiveness. The innovation of this new model lies in treating maintenance-effectiveness parameters as uniformly distributed random variables, thereby breaking away from conventional thinking.