تجزیه و تحلیل در دسترس بودن تولید میل لنگ در صنعت خودرو دو چرخ

The paper describes the availability of crank-case manufacturing system in an automobile industry. The units discussed here fail either directly from normal working state or indirectly through partial failure state. The machines are subjected to both preventive and corrective maintenance. Failure and repair times of the units are independent. The problem is formulated using probability consideration and supplementary variable technique. The system of equations governing the working of system consists of ordinary as well as partial differential equations. Lagrange method and Runge–Kutta method is used to solve partial differential equation and ordinary differential equation respectively. The study reveals that successful program of preventive and routine maintenance will reduce equipment failures, extend the life of the equipment, and increase the system availability to considerable margin.

Reliability, in general, can be defined as the ability of a system to perform its required functions under stated conditions for a specified period of time. Reliability technology is an important phenomenon of the existing era. This technology is widely used to increase the efficiency of the system. To overcome day-to-day problems, now a day, the system analysts and engineers are interested in the analysis of reliability models to implement them for practical utility. The paper consists of a brief discussion of method of calculating availability for idealized and faulty preventive maintenance. The problem is also reduced to the case when no preventive maintenance (PM) is done. The paper also presents the steady state and transient study of the system in evaluation of availability. The primary action of the preventive maintenance is to control the condition of the system and to ensure its availability. Efficiency of PM also affects the operational behavior of the system. Perfect and efficient PM means no damage and no error during maintenance operation. The faulty and inefficient PM means that either replaced component may not have worked properly or maintenance personal may have damaged the equipment. Corrective maintenance (CM) is the maintenance action carried out to restore a defective system or component to an operative condition. Many authors have studied preventive maintenance systems. Barlow and Hunter [1] studied the preventive maintenance models with minimal repairs. Singh [2] computed the state probabilities of a complex system having four types of components with preemptive repeat priority repairs. Zhang [3] studied the stochastic behavior of an (N+1)-unit standby system under preemptive priority repair rule and obtained the expressions for transient as well as steady states of the system using supplementary variable technique and Laplace transforms. Gandhi and Wani [4] evaluated maintainability index of mechanical system using digraph and matrix method. Grall et al. [5] presented a preventive maintenance structure for a gradually deteriorating single unit system. Kumar [6], Singh [7], Gupta et al. [8], Garg et al. [9] and some other workers applied reliability technology to various industrial systems obtaining important results. In the present paper, the production of a crank-case in a two-wheeler automobile company has been discussed in detail. The raw material used is raw crank-case. The paper focuses on the system availability, and obtained the valuable expressions for availability under various conditions. The system availability has been discussed for two states: transient state and steady state. Numerical analysis of availability of the system for transient state and steady state has been done by using Runge–Kutta method and software package MATLAB 5.1 respectively. Based on the analysis of system, suggestions have been made to optimize the production of system.

It is concluded that the availability of the system can be improved considerably by controlling deterioration of the system using proper maintenance planning and scheduling. Following the above findings and the results of numerical analysis carried out in the study in different field conditions, the management can derive cost cutting plans and increased productivity.