1. ME6012 MAINTENANCE ENGINEERING UNIT I PRINCIPLES AND PRACTICES OF MAINTENANCE PLANNING

2. MAINTENANCE  Maintenance is the routine work & recurring process of keeping a particular machine or asset in its normal operating condition.  So that expected performance / service is achieved without any loss or damage.

3. MAINTENANCE PLANNING  Maintenance planning is the task of organizing resources to carry out a job satisfactorily at reasonable cost within a specified period of time.

5. OBJECTIVES OF MAINTENANCE PLANNING  To ensure maintenance breakdown.  To ensure the availability of the machines in optimum working conditions.  To keep the time schedule of delivering to the customers.  To keep the maintenance costs as low as possible.  To control the cost of maintenance related activities.  To meet the quality requirements of the product.  To increase the profits of production systems.

6. THE PRINCIPLES OF MAINTENANCE  Plant management in maintenance work The main roles of a maintenance function is to provide safe and effective operation of the equipment to achieve the desired targets on time with economics usage of resources.

7.  Production and maintenance objectives The plant operation is driven by the production targets. The objective of maintenance function is to support these targets.

8.  Establishment of work order and recording system The maintenance system should have proper work and recording system. To indicates the nature of work To execute a particular job To maintain proper records / to monitor the maintenance function.

9.  Information based decision making. To meet the manpower and spare parts requirements of the industry.

10.  Planning of maintenance function To ensure the effective utilization of manpower and materials.

11.  Manpower for maintenance Satisfy the need arising at the time of overhauls, component replacement, emergency and unscheduled repair.

12.  Work force control Difficult to determine the exact work force So proper control and monitoring of workforce are to be ensured.

13.  Role of spare parts Appropriate tools are needed for good maintenance system.  Training of maintenance work force.

14. IMPORTANT FACTORS TO BE CONSIDERED IN MAINTENANCE PLANNING  Job distribution  For preventive and emergency maintenance.  Neither under utilization nor over utilization.  Programme  Objective is to reduce the system cost for providing services.

15. Maintenance programs involves  Selection of activities/ to select preventive or breakdown maintenance  Determine the of frequency of preventive maintenance (determined from the failure data)  Cost effective methodology (either repair or replacement)

16.  Manpower allocation Allocation can be drafted from the maintenance records and planning the task to meet the objectives.  Staffing Staffing should be sufficient to handle preventive and emergency maintenance task.

17.  Planning Technique To developed overall master plan for scheduling the major work of planning and execution.  Planning procedure Organizing maintenance resources, Scheduling Execution Establishing a feedback system.

18. Bath tub curve Or Equipment life cycle

19. Maintainability  Maintainability is defined as the probability of performing a successful repair action within a given time.  In other words, maintainability measures the ease and speed with which a system can be restored to operational status after a failure occurs.

20. Availability  Availability is the ratio of the time at which equipmet is available for the designated operation /service to the total time of operation and maintenance of the equipment.

21. Types of availability  Inherent availability Ai = MTBF/(MTBF + MTTR)  Achieved availability Aa = MTBM/(MTBM + MAMT) MAMT - Mean active maintenance time.  Operational availability Ao = MTBM/(MTBM + MDT) MDT - Mean down time.

22. Mean Time Between failures (MTBF)  The total time required for a device to fail and that failure to be repaired.  The sum of MTTF and MTTR.

23. Mean Time to Repair (MTTR)  Mean Time To Repair (MTTR) is a basic measure of the maintainability of repairable items.  It represents the average time required to repair a failed component or device.

24. Mean Waiting time (MWT) Mean Waiting Time is part of the down time indicating the mean down-time lost in waiting for materials or labour for attending to a break down. Mean waiting Time is the ratio of Total Machine Hours lost due to waiting for materials or labour to the total number of breakdowns.

25. Maintenance organization Types of Maintenance organization Decentralised Centralised Partially centralised

26. Decentralised  Suitable for large size plants  Maintenance is under the control of chief engineer of production

27. Centralised  Suitable for small units  Maintenance is under the control of chief Maintenance engineer.  Responsibility is with concerned department heads

28. Partially Centralised  Suitable for industry where units are located at far away locations.  Production unit will carry out routine maintenance work.

29. Typical Organization structure

30. Maintenance in Service Industry Hospital Restaurants Transport companies Banks Hotels and resorts Shopping malls / retail Gas station

31. Introduction to the concept of planning 1.Long-rang planning: It covers a period of 3 to 5 years and sets plans for future activities and long-range improvement. Replace oil in manual transmission. Replace oil in automatic transmission if using synthetic. Replace oil in differentials and transfer case. Check and adjust pocket-style valves Replace rubber timing belts on camshafts

32.  Medium-range planning: it covers a period of 1 month to 1 year. Change oil and filter. Replace all filters (air, fuel, PCV). Lubricate chassis. Check brakes and wheel bearings. Check and adjust valves if rocker-type arm. Check all belts including timing belt. Check temperature for engine thermostat. Replace plugs, points, cap, rotor, and all necessary tune-up and emission items. Inspect cooling system hoses and fluid for cleanliness. Check for leaks and other problems

33. . Short-rang planning: it covers a period of 1 day to 1 week. It focuses on the determination of all the elements required to perform maintenance tasks in advance EVERY 3,000 MILES Change oil and filter. Check all fluids. Check tire pressure. Check all belts and hoses. Lubricate chassis.

34. Preventative Vehicle Maintenanance Check List  Air Filter  Check the air filter every other month.  Replace it when it’s dirty or as part of a tune-up.  Battery  Use extreme caution when handling a battery since it can produce explosive gases.  Do not smoke, create a spark or light a match near a battery and always wear protective glasses and gloves.  Have it checked with every oil change.  Cables should be attached securely and be free of corrosion.

35.  Belts  Inspect belts and hoses monthly.  Replace worn, glazed or frayed belts.  Tighten them when more than 1/2” of slack can be depressed between the pulleys.  Vehicles with spring belt tensioners require no adjustment.  Brake Fluid  Check brake fluid monthly.  First, wipe dirt from the brake master cylinder reservoir lid.

36.  Engine Oil  Check oil every other fill up. Remove the dipstick, wipe it clean. insert it fully and remove it again. If it is low, add oil.  To maintain peak performance, change oil every 3,000 miles or 3 months, whichever comes first. Replace oil filter  Exhaust  Look underneath for loose or broken exhaust clamps and supports.  Check for holes in muffler or pipes.  Replace rusted or damaged parts.  Have emission checked at least once per year.

37.  Lights Be sure all your lights are clean and working, including brake lights, turn signals and emergency flashers. Keep spare bulbs and fuses in your vehicle.  Oil Filter To maintain peak performance, change oil every 3,000 miles or 3 months.  Power Steering Fluid Check power steering fluid level once per month. Simply remove the reservoir dipstick. If the level is down, add fluid and inspect the pump and hoses for leaks.

38.  Shock Absorbers  Look for signs of oil seepage on shock absorbers, test shock action by bouncing the car up and down.  The car should stop bouncing when you step back.  Worn or leaking shocks should be replaced.  Always replace shock absorbers in pairs  Tires  Keep tires inflated to recommended pressure (it helps to own your own gauge).  Check for cuts, bulges and excessive tread wear.  Uneven wear indicates tires are misaligned or out of balance.  Keep a record of tire rotation. Rotate at the first 5,000 miles and every 7,500 miles thereafter.

39. Transmission Fluid  Check transmission fluid monthly with engine warm and running, and parking brake on.  Shift to drive, then to park.  Remove dipstick, wipe dry,insert it and remove it again. Add the approved type fluid, if needed.