Suggestion Schemes (contd…)

Prepared by: Bhakti JoshiDate: February 21, 2013

Total Productivity Maintenance: Brief Case Study

Hindalco manufactures aluminium products in its Renukoot plant in Uttar Pradesh. The plant has significant downtime. A team of workers identified three main reasons for equipment downtime.-Excessive time required for replacement of gaskets in an equipment-Failure of valve resulting in 12 oil-seal replacements in a year-Inappropriate insulationThe team realised the problems and eliminated them thus leading to the following:1.After eliminating the need for replacing 1,152 gaskets, 3,744 hours of productive machine time was reclaimed2.Eliminating oil-seal replacements led to reclaiming 1,536 hours3.Developing better insulation at a cost Rs. 1,780 per year, fuel savings worth Rs 4,150 were made and painting cost worth Rs 1,500 per equipment was also avoidedOverall, equipment downtime was cut by 87.16% and an annual savings of Rs. 123,000 was also achieved. The entire process was done by an empowered work force, which also perceived job enrichment

TPM stands for…

• Maintenance and production individuals working together (Total)

• Production of goods/services that meet or exceed customers’ expectations (Productive)

• Keeping equipment and plant in good or better condition than original condition at all time (Maintenance)

Goals of TPM

• Equipment capacities maintained and improved always

• Aiming towards maintaining equipment for life

• Using support from all areas of operation• Encouraging input from all employees• Using teams for continuous improvement

TPM concept: Overall Equipment Effectiveness (OEE)

OEE = Availability (A) X Performance (E) X Quality (R)

A = (T/P) x 100

A= AvailabilityT = Operating time (P-D)P = Planned operating timeD = Downtime

E = C x N x 100

E= PerformanceC = Theoretical cycle timeN = Processed amount (quantity)

T( ) R = N - Q x 100

R= Rate of QualityQ = Non-conformitiesN = Processed amount (quantity)

N( )

Example 1Week 1’s production numbers on machining center JL58 were as follows:•Scheduled operation = 10 hours/day; 5 days/week•Manufacturing downtime due to meetings, material outages, training, breaks and so forth = 410 minutes/week•Manufacturing downtime scheduled and equipment breakdown = 227 minutes/week•Theoretical (standard) cycle time = 0.5 minutes/unit•Production for the week = 4450 units•Defective parts made = 15 units

Example 1 (contd…)P = 10 hours/day X 5 days/week X 60 minutes / hour = D = 410 minutes/week + 227 minutes/week = T = (P-D) = C = N = Q = Availability = Performance = Quality = Therefore OEE =

3000 minutes / week 637 minutes /

week2363 minutes / week

0.5 minutes / unit4450 units15 units

78.8%94.2%99.7%

0.740 or 74%

Example 1 (contd…)Week 2’s production numbers on machining center JL58 were as follows:•Scheduled operation = 8 hours/day; 5 days/week•Manufacturing downtime due to meetings, material outages, training, breaks and so forth = 309 minutes/week•Manufacturing downtime scheduled and equipment breakdown = 200 minutes/week•Theoretical (standard) cycle time = 0.5 minutes/unit•Production for the week = 4550 units•Defective parts made = 10 units

Example 1 (contd…)P = 8 hours/day X 5 days/week X 60 minutes / hour = D = 309 minutes/week + 200 minutes/week = T = (P-D) = C = N = Q = Availability = Performance = Quality = Therefore OEE =

2400 minutes / week 509 minutes /

week1891 minutes / week

0.5 minutes / unit4550 units10 units

0.7879 or 78.79%1.203 or 120.3%

0.9978 or 99.78%0.787 * 1.203* 0.997=0.945 or 94.5%

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