Optimization of equipment maintainability in the h

Optimization of equipment maintainability in overhaul and technical transformation

the two major objectives of maintenance work are: to prevent failures on the basis of cost optimization; Eliminate the faults that have occurred. To achieve the above goals, in addition to requiring high reliability of the equipment, good maintainability is also essential

maintainability refers to the performance of equipment during maintenance under given conditions. According to Blanchard, an American scholar, maintainability is an inherent attribute formed in the process of equipment design, manufacturing and installation. It directly involves the maintenance measures, but we all know the feasibility, economy, safety and accuracy. Maintainability is a design parameter, and maintenance is the result of design. In this sense, the optimization of equipment structure is very important for maintainability. In addition, like reliability, the realization and optimization of maintainability are also inseparable from the maintenance management in the use stage

since maintainability is an inherent attribute of equipment, its optimization must start with improving the structure of equipment. For the old equipment existing in Chinese enterprises, its maintainability is generally poor. It is a very necessary work to partially adjust or improve the structure of these equipment during overhaul or technical transformation to improve its maintainability. 1、 The connotation of good maintainability as far as the equipment itself is concerned, good maintainability should be reflected in: accessibility and disassembly during equipment maintenance; Replaceability of mechanism and parts; The testability and identifiability of equipment faults; Sensory inspection is mainly active in the possibility of equipment failure in the lubricating oil industry; Easy emptying and filling of fluid; Easy identification of various pipelines and materials; Application of modular, plug-in and standardized parts, etc

different types of equipment have different specific requirements for maintainability. For example, for machining equipment, good maintainability should be good accessibility; High replaceability; Assembled (plug-in and modular parts) structural type; Standardized measuring and control components; Clearly marked and built-in pipelines; Automatic and central lubrication system; Automatic chip removal device; Separate drive and control elements, etc. 2、 The relationship between equipment structure and maintainability is shown in Table 1. 3、 The way to optimize the maintainability of equipment in the overhaul or technical transformation of equipment, first of all, it should be based on the actual situation. 1. Transmission: there are lead screw transmission and rack transmission. According to the functions of different subsystems of the equipment and the environmental conditions in which the diamond square cone press with a load within 120kg and a vertex angle of 136 ° is pressed into the material surface, specific and quantitative maintainability indicators should be formulated and corresponding structural improvements should be made. For different schemes, the maintainability index shall be compared and evaluated, and the test and evaluation under simulated conditions shall be carried out if necessary. On the basis of evaluating the maintainability of all subsystems, put forward overall quantitative requirements for the maintainability of equipment systems. Table 1 maintainability marks, optimized structure and configuration, easy identification of faults, application of various marks, symbols, charts, colors,

installation and configuration of test points, accessibility of maintenance such as status display and monitoring devices, sufficient maintenance space, installation and configuration of inspection holes, guard plates,

protective covers, test points, replaceability, detachability of parts, modular, plug-in and standardized parts,

Application of bolt connection, insertion (positioning) pin, locking device, clamping device, easy emptying and easy filling filling hole (device), discharge hole (device),

material position display and monitoring device, filter and other lubrication points with appropriate lubricity, automatic and central lubrication system,

status display and monitoring device, filter and other testing points with appropriate testability, test connection, status display and monitoring device

when designing the maintainability structure of automatic test device and adjustment device, the failure mode, failure characteristics and failure consequences of the original equipment should also be analyzed according to the accumulation of previous data, data and experience, and the maintenance consumption under different design conditions should be determined from the economic level. On this basis, the maintainability design variables are analyzed and evaluated, and the maintainability test is carried out through the model. Finally, according to the improved maintainability, the original maintenance and inspection scheme of the equipment is modified for the user, and the original planned repair scheme is optimized

during the test run of the equipment after overhaul or technical transformation, attention should also be paid to the impact of the modified maintenance scheme on maintainability, so as to be finally determined

the influence of the maintenance management in the equipment use stage, that is, the so-called "logistics boundary conditions" on the inherent attribute of the equipment maintainability can not be ignored. For example, the effective configuration of professional maintenance personnel, spare parts, maintenance equipment and tools, maintenance plan, optimization of maintenance strategy and arrangement of maintenance management are all essential elements related to the optimization of equipment maintainability. Author Tonglian: Zhang Youcheng (Department of mechanical and electrical engineering, Beijing campus, China University of mining and technology, Beijing 100024, No. 2, Dingfuzhuang, Chaoyang Gate, Beijing)