Unit 8 maintainance management pptx

Diploma Mechanical Engg

1. Maintenance management unit 8 Dr. Rashmi Panwar

2. meaning Maintenance activities are related with repair, replacement and service of components or some identifiable group of components in a manufacturing plant so that it may continue to operate at a specified ‘availability’ for a specified period. Thus maintenance management is associated with the direction and organization of various resources so as to control the availability and performance of the industrial unit to some specified level.

3. importance Maintenance management is responsible for the smooth and efficient working of the industrial plant and helps in improving the productivity. It also helps to keep the machines/equipment in their optimum operating conditions. Thus plant maintenance is an important and inevitable service function of an efficient production system.

4. It also helps in maintaining and improving the operational efficiency of the plant facilities and hence contributes towards revenue by decreasing the operating cost and improving the quality and quantity of the product being manufactured. As a service function it is related with the incurrence of certain costs. The important component of such costs are — employment of maintenance staff, other minor administrative expenses, investment in maintenance equipment and inventory of repair components/ parts and maintenance materials.

5. Absence of plant maintenance may lead to frequent machine breakdown and failure of certain productive centres /services which in turn would result in stoppages of production activities, idle man and machine time, dislocation of the subsequent operations, poor quality of production, failure to meet delivery dates of product supply, industrial accidents endangering the life of workers/ operators and allied costs etc.

6. Types of maintenance systems 1 - Corrective maintenance Corrective maintenance is implemented right after a defect has been detected on a piece of equipment or a production line: its objective is to make the piece of equipment work normally again, so that it can perform its assigned function. Corrective maintenance can either be planned or unplanned depending on whether or not a maintenance plan has been created

7. 2 - Predetermined maintenance Predetermined maintenance, probably the less known one of all the maintenance types presented in this article, doesn’t rely on the actual equipment’s state but rather on the programs delivered by manufacturers. They elaborate these programs based on their knowledge of failure mechanisms as well as on MTTF (mean time to failure) statistics which they observed on a piece of equipment and its various components in the past.

8. 3 3 Condition-based maintenance Among all types of maintenance cited above, the condition-based maintenance is the most complicated to implement. It aims to prevent failures and requires regular check-ups of the state, the efficiency as well as other indicators of the system. All this data can be gathered automatically on the field or remotely thanks to a direct network connection to the equipment, in order to make sure that it is constantly controlled. Maintenance teams can decide whether they want to operate constant or regular interval control: they read counters, check parts’ wear, control motors’ temperatures… These are all actions the teams can undertake to ensure that no piece will cause a breakdown that would damage the whole production line .

9. 4 - Preventive maintenance Preventive maintenance is applied by technicians teams and managers before any breakdown or failure occurs. Its aim is to reduce the probability of breakdown or degradation of a piece of equipment, component or spare part. In order to implement such maintenance, teams have to take the part’s history into consideration and keep track of the past failures. They are therefore able to identify the time ranges during which a piece of equipment might break down.

10. 5 - Towards predictive maintenance? A next-gen CMMS(computerized maintenance management system) like Mobility Work, a solution that offers a performing analytics tool able to gather all the data entered by maintenance teams themselves, aims to progressively help plants evolve towards predictive maintenance. It allows technicians to anticipate breakdowns: they generate reports directly in their maintenance management software, they know when a piece of equipment might break down and therefore proceed to industrial maintenance operations. Once again, the most important thing is anticipation because any failure could slow down the production and become extremely costly. Predictive maintenance can be implemented thanks to an intuitive and easy to use CMMS, which will ease industrial maintenance technicians’ lives and generate tables and graphs for them thanks to all the data entered by all their colleagues.

11. objectives (1) Minimizing the loss of productive time because of equipment failure to maximize the availability of plant, equipment and machinery for productive utilization through planned maintenance. (2) To extend the useful life of the plant, machinery and other facilities by minimizing their wear and tear. (3) Minimizing the loss due to production stoppages. (4) To ensure operational readiness of all equipment’s needed for emergency purposes at all times such as fire-fighting equipment.

12. (5) Efficient use of maintenance equipment’s and personnel. (6) To ensure safety of personnel through regular inspection and maintenance of facilities such as boilers, compressors and material handling equipment etc. (7) To maximize efficiency and economy in production through optimum utilization of available facilities. (8) To improve the quality of products and to improve the productivity of the plant. (9) To minimize the total maintenance cost which may consist of cost of repairs, cost of preventive maintenance and inventory costs associated with spare parts/materials required for maintenance.

13. The Bath tub curve

14. The bathtub curve is generated by mapping the rate of early "infant mortality" failures when first introduced, the rate of random failures with constant failure rate during its "useful life", and finally the rate of "wear out" failures as the product exceeds its design lifetime. In less technical terms, in the early life of a product adhering to the bathtub curve, the failure rate is high but rapidly decreasing as defective products are identified and discarded, and early sources of potential failure such as handling and installation error are surmounted. In the mid-life of a product—generally speaking for consumer products—the failure rate is low and constant. In the late life of the product, the failure rate increases, as age and wear take their toll on the product. Many electronic consumer product life cycles strongly exhibit the bathtub curve. While the bathtub curve is useful, not every product or system follows a bathtub curve hazard function, for example if units are retired or have decreased use during or before the onset of the wear-out period, they will show fewer failures per unit calendar time (not per unit use time) than the bathtub curve.

15. The bathtub curve is widely used in reliability engineering. It describes a particular form of the hazard function which comprises three parts: The first part is a decreasing failure rate, known as early failures. The second part is a constant failure rate, known as random failures. The third part is an increasing failure rate, known as wear-out failures. The name is derived from the cross-sectional shape of a bathtub: steep sides and a flat bottom.

16. Activities involved ( 1) To develop maintenance policies, procedures and standards for the plant maintenance system. (2) To schedule the maintenance work after due consultation with the concerned production department (3) To carry out repairs and rectify or overhaul planned equipment/facilities for achieving the required level of availability and optimum operational efficiency. (4) To ensure scheduled inspection, lubrication oil checking, and adjustment of plant machinery and equipment.

17. (5) To document and maintain record of each maintenance activity (i.e., repairs, replacement, overhauls, modifications and lubrication etc.). (6) To maintain and carry out repairs of buildings, utilities, material handling equipment’s and other service facilities such as electrical installations, sewers, central stores and roadways etc. (7) To carry out and facilitate periodic inspections of equipment and facilities to know their conditions related to their failure and stoppage of production. (8) To prepare inventory list of spare parts and materials required for maintenance.

18. ( 9) To ensure cost effective maintenance. (10) To forecast the maintenance expenditure and prepare a budget and to ensure that maintenance expenditure is as per planned budget. (11) To recruit and train personnel to prepare the maintenance workforce for effective and efficient plant maintenance. (12) To implement safety standards as required for the use of specific equipment or certain categories of equipment such as boilers, overhead cranes and chemical plants etc.

19. (13 ) To develop management information systems, to provide information to top management regarding the maintenance activities. (14) To monitor the equipment condition at regular intervals. (15) To ensure proper inventory control of spare parts and other materials required.

20. THANK YOU