It indicates the expected time between two failures for a fixable machine or system.
→ MTBF =( (Total working time)- ( Total Breakdown time))/ (No of Breakdowns) or = ( Total uptime)/ ( number of breakdowns)
→ It's really important for Total Productive Maintenance (TPM) implementation which is one of the most popular Lean Manufacturing Tool.
MTBF Calculation
→ Three similar machines functioning properly at 0 hours are working until all of them fail. → The first machine failed at 120 hours, the second failed at 140 hours and the third failed at 150 hours.
→ The MTBF = ( Total uptime)/ ( number of breakdowns) = ( (120140150))/ 3 = 136.667 hours.
→ The MTBF is the normal of the three failures, which is136.667 hrs.
→ It can be calculated as the arithmetic mean between the failures of equipment.
→ In other words, It's the average duration between the failure of equipment.
→ This value136.667 means that a failure in the system occurs every136.667 hours and it generates losses to the company.
→ The chance is to increase the duration between two breakdowns. → In other words, the MTBF is the timing from one failure to another for fixable equipment.
How can I improve my MTBF?
→ We can improve it by regular maintenance of machines.
→ By implementing small Kaizen activity for the equipment. → Make an equipment breakdown history book and take a strong preventing action on it so this breakdown won't repeat in the future.
Benefits of MTBF
→ It's a fundamental indicator to predict the trustability of a machine.
→ Ifthe_MTBF has increased after a preventive maintenance activity also this indicates a clear improvement in the quality of your processes
→ It's really useful for implementing Lean Manufacturing culture in the plant. →The MTBF increase will show that your maintenance or verification methodologies are going good.
→ It should be used to elaborate on the company’s knowledge about processes.
→ It reduces losses in productivity and also improves the quality of the product
What's MTTR (Mean Time To Repair)?
→ It's the average time needed to analyze and solve the problem and it tells us how wellan association can respond to machine failure and repair it.
→ In other words, failed equipment returns to normal operating conditions or the mean timing duration between the equipment failure and returns to operation.
→ It's a fundamental specialized indicator related to the maintainability of the machine andrepairable parts.
→ It represents the average duration needed to repair a failed element.
→ In other words, how long the machine is out of production.
→ This includes notification timing, analysis timing, fixing timing, staying, reassembly timing, alignment timing, calibration timing, testing timing, etc.
→ The formula of MTTR = Total maintenance time/ number of repairs → It's also called as the meantime to recovery.
MTTR Calculation
→ A machine should operate rightly for 20 hours. During this period, 6 failures occurred. The sum of all failure duration is 90 minutes.
→ The MTTR = Total maintenance time/ number of repairs = 90/ 6 = 15 minutes
Why MTTR is important?
→ It has a remarkable effect on the association’s profit.
→ Long MTTR means loss of productivity and now and then, an association can miss an orderor it can impact business relationships.
→ To reduce the impact of MTTR, associations should have their own maintenance teams and hold critical spare parts onsite or run parallel production lines.
How can I improve my MTTR?
→ We can improve it by Team Work.
→ Implement and follow the troubleshooting manual concept or breakdown history concept
→ By give training on quick form and motivate people
→ Maintaining 5S
→ Follow the standardized operation procedure.
→ Keep the critical extra in stock
Benefits of MTTR
→ It indicates the efficiency and productivity of the equipment and it has reduced after the precautionary maintenance of the machine.
→ By reducing Mean Time To Repair we can improve the efficiency and productivity of the machine.
→Lower_MTTR indicates that your company has an immediate action plan to overcome failure.
→ It should be used to elaborate on the company’s knowledge about how strong the action plan against the machine failure.
→ It reduces losses and also improves productivity and Quality of the Product.
→ It's really useful for implementing Lean Manufacturing culture in the plant.
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