All activities involved in keeping a system’s equipments working are the part of maintenances management. Maintenance of machine involves the efforts directed towards the upkeep and repairs of that machine. Maintenance are the set of activities performed to keep an equipment in the specified condition or it is remedial action to restore the equipment to its specified condition. Maintenance can be improved by enlarging repair crews, by increasing repair capabilities and providing more inventory of replacement items.

 Maintaining system capability  Minimizing total costs  Ensuring maximum plant availability by preventing unexpected breakdowns and by reducing shutdown periods  Maintenance of equipment and its rated productivity and original accuracy  Elimination of unsafe conditions that cause accidents thereby ensuring safety of workmen  Minimization of wear and tear to increase the longevity of the equipment

 Excessive friction between the parts  Failure to replace parts that are known to wear  Neglected cooling system  Neglected common minor faults  Overloading of machines, wrong fuel, obstruction of air intakes, faults in another items of equipment  Design or manufacturing defects of the equipment  Installation deficiencies  Improper handling of the machines by the oprators

 Down time cost  Idle wages  Loss of material  Cost of repairs  Opportunity costs  Effect on another machines  Tool breakage  Overtime wages paid to the maintenance  Higher costs for urgency of spare parts

 For keeping Plants and equipments in good working conditions plants and equipments are the heart of the production system, therefore proper maintenance of plant and equipments is essential for keeping them in good working condition. This ensures optimum utilization of production facilities and resources. All production equipments are designed to give a predetermined quantity and quality of output. This objective can be achieved by proper maintenance.

 For maximizing the production performance Proper maintenance helps to maximize the production performance by preventing breakdowns and by minimizing the loss caused by breakdowns. In a developing country like India, maintenance has a significant importance. The capital is scarce and its best possible use is essential. Moreover, the natural conditions like climate and extreme humidity requires special upkeep of equipment. Proper maintenance results in better performance and longer life of machinary.

 Planned maintenance a)Preventive maintenance b)Corrective maintenance  Unplanned maintenance  Routine maintenance a) Running maintenance b) Shutdown maintenance

Planned maintenance refers to the system of maintenance wherein the maintenance work is planned in advance, work is executed as per schedule, actions taken are recorded on completion, historical and statistical records so produced and maintained are revived/ analyzed to identify the gaps/ deficiencies in planning and feedback is utilized to devise strategies for accomplishing better performance.

It anticipated failure and adopts necessary actions to check failure before they occurs. It includes activities like inspections, lubrications, cleaning and upkeep, minor adjustments and replacements found necessary at the time of inspection. Preventive maintenance is one of the key activities of preventive maintenance which is usually performed by making use of human sense- watch(eyes), hear(ear), touch(hand,leg, body), smell(nose), and taste(tongue)- but the trend is now changing towards use of condition monitoring instruments. Such a maintenance practice is known as predictive maintenance or condition based maintenance.

Preventive maintenance can significantly reduce the rate of wear and tear of machinery but cant wholly eliminate it. Equipment thus functionally degrades over a period and its performance gradually drops below is acceptable limits. Corrective maintenance is the maintenance work undertaken to compensate for wear and tear, planned either on yearly, six monthly, or some other basis, to restore the equipment back to an acceptable condition.

Since in spite of elaborate planned maintenance system, chance equipment failure can still occur, the firm will always have some unplanned maintenance work. Unplanned maintenance thus is the maintenance work performed which is not planned in advance. a) Emergency maintenance b) Breakdown maintenance