Different inspection priorities for moving and stationary equipment, as well as zero-failure equipment management

Thread Content

Key inspection points for moving and stationary equipment, as well as zero-failure equipment management (I) Inspection contents of equipment: 1. Common issues related to ‘leaking, escaping, dripping, and seeping’； 2. Check whether the basic instrument parameters of the equipment are normal, such as pressure, current, temperature, flow rate, vibration, oil level, etc ； 3. Inspection of the connection parts of important equipment: such as the couplings of reducers, the noise emitted by reducers, the level and condition of lubricating oil, and whether the foundation bolts of reducers are loose, etc ； 4. Are there any instances of non-compliant operations? ； 5. Understanding of equipment shift handovers. (II) Specific inspection items for moving and stationary equipment: For moving equipment: 1. Use inspection methods such as looking, listening, and touching ； 2. Visual inspection: Check its operating status and the readings on the relevant gauge instruments (pressure, temperature, oil level, current, etc.) ； 3. Second listening: Listen to the operating sound to check for any abnormal noises ； 4. Three-touch test: Check whether there are any abnormal vibrations in the operation of the device, which can be done using relevant measuring instruments such as vibration meters. For static equipment: 1. Mainly check its appearance ； 2. Integrity of connection components ； 3. Operating status of relevant instruments (on-site primary meters) ； 4. Issues such as running, leaking, dripping, and seeping. Differences in the inspection of static and dynamic equipment: Static equipment: Simply put, it involves checking for any differences from normal conditions; an even minor anomaly can indicate a potential hazard. Movable equipment: The main thing is to listen for any differences in the sound compared to normal conditions. After spending time at the post, it becomes easy to do this, as one becomes very familiar with the sound of the equipment operating properly over time; if there are issues with its operation, the sound will definitely be different. It is also necessary to check the lubricant level and the temperatures at the key control points of the bearings (regular communication with the control room can be used for verification). With the rapid development of the market economy, enterprises face increasing competitive and cost pressures; minimizing production costs and maximizing economic efficiency have thus become the goals that enterprises strive to achieve. Against this backdrop, the so-called zero-failure equipment management emerged. Zero-failure equipment management 1. The concept of zero-failure equipment Simply put, zero-failure equipment means using appropriate maintenance methods to inspect the equipment before failures occur, eliminating potential faults and defects so that the equipment remains in good working condition at all times. 　　Regarding the concept of zero failures, it should be noted that: (1) Zero failures does not mean that equipment will never malfunction; rather, it means making every effort to prevent any failures from occurring and to maintain stable production operations. (2) Zero failures is a systematic concept. It is not difficult for an individual piece of equipment to achieve zero failures, but minimizing the impact of its downtime for maintenance on production is a complex process that requires taking into account the overall condition of the production equipment as well as the overall economic efficiency of the production system. (3) The core of the zero-failure concept is to eliminate unplanned shutdowns and emergency repairs. The losses caused by unplanned shutdowns and emergency repairs are enormous, and the consequences can sometimes be very severe. 2. Causes of zero equipment failures and equipment failure modes There are many reasons for equipment failures, as well as various classification methods; the following discusses them briefly from a few perspectives only. 　　2.1 Equipment failures from the perspective of the equipment’s service life can be divided into two categories: Inherent failures – those caused by inherent defects in the equipment resulting from improper design or manufacturing. 　　Functional failures – failures caused by factors such as installation and maintenance, operation, and natural deterioration of the equipment. 　　2.2 Factors contributing to equipment failures Strictly speaking, inherent defects in equipment are a type of human-caused failure; these defects are related not only to the skill and sense of responsibility of the designers and manufacturers but also to the stage of development of science and technology. 　　After the equipment is in operation, careful operation and daily maintenance become the most important human factors. As the ancients said, “Disasters often lie hidden in subtleties, emerging where people fail to pay attention.” 　　2.3 Equipment failure modes Equipment failure modes are primarily reflected in the bathtub curve; different devices have distinct failure patterns. Therefore, in practice it is necessary to carefully study the specific failure patterns and characteristics of a particular device, and to adopt appropriate maintenance, care, and repair methods accordingly. For early failures, it is necessary to conduct in-depth studies of various failure symptoms, investigate the causes of equipment accidents, and determine corresponding countermeasures and actions. During the equipment’s wear period, it is necessary to avoid sudden failures; TPM (Total Productive Maintenance) should be strengthened, various monitoring techniques should be widely applied to understand the operating trends of the equipment, and management of equipment degradation trends should be carried out. 3. Analysis of maintenance methods for zero-failure equipment management For equipment used in production processes, reactive maintenance is not advisable. Therefore, the maintenance methods under zero-failure management include the following aspects: preventive maintenance (also known as regular maintenance), predictive maintenance, and proactive maintenance (also known as corrective maintenance). The above three maintenance methods constitute the basic framework of Reliability-Centered Maintenance (RCM), and a comparative analysis is shown in Table 1. In summary, the maintenance approach of zero-failure management aims to address the questions of \"when to repair\" and \"how to repair\". 4. Discussion on approaches to achieving zero equipment failures Zero-failure equipment management is a complex systematic project, and its management process is comprehensive. It requires the participation of all employees (from supervisors to operators and maintenance staff) and its application throughout the entire process (in all stages of equipment management). The process of achieving zero-failure device management is also a process of improving corporate culture building. The approaches to achieving zero equipment failures are discussed from the following aspects. 　　4.1 Reducing the probability of failures by minimizing equipment defects Equipment defects lead to equipment failures, and equipment failures result in accidents. “\"A dike a thousand miles long can be ruined by an ant hole.\" To achieve zero equipment failures, it is necessary to start by reducing equipment defects. The basic activities for reducing equipment defects are: 5S activities: Seiri, Seiton, Seiso, Seiketsu, and Shitsuke ； 　　6S activities: Sorting, Straightening, Cleaning, Sanitizing, Standardization, Safety ； 　　The 8-character guideline: Sorting, straightening, lubrication, and adjustment. 　　4.2 Standardization The process of reducing defects is an ongoing one; to achieve an ideal state, it is necessary to establish standardized operating procedures. Standardization forms the basis for the aforementioned activities and is the essence of all management work. The standardization process is one that progresses from small to large, from simple to complex; it is not possible to achieve perfection in just one step, and standardized documents need to be continuously revised and improved. 　　4.3 Implementing TPM and RCM In fact, the basic activities and standardization efforts mentioned earlier for reducing defects are precisely the essence of TPM, which is characterized above all by full employee participation. RCM, see Table 1. It starts with preventive maintenance, scheduling planned inspections based on the results of equipment condition monitoring in order to achieve the highest equipment utilization and the lowest maintenance costs. 　　4.4 Strengthen equipment condition monitoring and fault diagnosis This is an effective way to avoid equipment failures and unexpected accidents. At the current stage, for Zhongtian Steel Company, equipment condition monitoring and fault diagnosis should focus on the following: (1) Continuously improving the two-level monitoring system of departmental inspections and shift inspections, implementing quantitative inspections, and truly extending condition monitoring and fault diagnosis techniques to shift teams and front-line workers – this is key to achieving zero equipment failures. (2) Develop standardized operation documents for equipment condition monitoring and simple fault diagnosis. (3) Strengthen the networked online monitoring and diagnosis of key equipment; vigorously promote the application of networked online monitoring technologies to detect potential equipment hazards at an early stage and prevent serious equipment accidents. (4) Attach importance to the training of diagnostic technicians. 　　4.5 Create a good working environment and show comprehensive care for employees. Based on monthly equipment failures, those caused by \"improper operation\" and \"inadequate maintenance\" account for one-third of all such failures, or even more. Why? In addition to the aforementioned basic activities and standardized operations not being carried out properly, it is also closely related to the enthusiasm and initiative of the employees. As the management levels of the company, they should carefully study this issue, starting by paying attention to all aspects of the employees’ work and living conditions. 5. Conclusion The preceding text discussed the concept of zero-failure equipment, the causes of equipment failures, and the equipment maintenance methods used in zero-failure management, with a focus on the specific approaches to implementing zero-failure management. To implement zero-failure management, it is essential to adopt entirely new concepts and ways of thinking ； There is no unified model for implementing zero-failure management; it should be continuously discussed and refined through practice ； Implementing zero-failure management will undoubtedly have a profound and lasting impact on all aspects of basic equipment management.