Total Productive Maintenance (TPM)
Total productive maintenance or TPM as it is known is a focussed effort by both maintenance/engineering teams and plant operating teams in both improving and maintaining a reliable and efficient plant which is able to run and produce acceptable quality finish goods whenever required without interruptions or breakdowns.
TPM is a comprehensive approach to maintenance. It takes into account the needs of all stakeholders and is performed continually. Total productive maintenance is part of a continuous improvement program and is achieved through a well planned maintenance schedule, plant life-cycle management, adequate spares and tools management, and empowerment of production crews in autonomous maintenance and plant inspections. TPM can also help reduce unscheduled maintenance for breakdowns, plant downtime, shorten changeover times and increase OEE. These improvements are obtained over time and are sometimes not readily visible after the implementation of a TPM system.It is important that all TPM focus initiatives to be led by senior professional that must set this framework into place and also motivate the team through the sometimes rigorous analysis and implementation of actions to achieve the desired improvement in productivity and efficiency.
Total Productive Maintenance Focus Areas
Total Productive Maintenance usually focusses on one piece of equipment or plant area at a time on the following losses of production and breakdowns: (The examples below are for an ore processing plant at a mine site)
-Unscheduled maintenance downtime (breakdowns)
Example: Unexpected breakdown of a bearing on the drive motor of the jaw crusher
-Premature ware of plant items
Example: Premature ware of the ore in-feed rubber conveyor belt
-Product changeover extended downtime
Example: Adjustment of crushing plant to enable crushing of harder ore resulting in incorrect adjustment of plates resulting in plate cracking
-Out of spec product quality
Example: Incorrect setup of crushing plant resulting in incorrect particle size
-Production yield losses
Example: Incorrect setup of crushing plant resulting in spill over of feed and lost production
-Production process downtime and smaller stoppages
Example: Incorrect disassembly of crushing plant for cleaning by operator crews due to lack of knowledge on plant items.
Total Productive Maintenance practical activity steps
The first step is the collection of stoppage, breakdown and product quality data for the plant and equipment being analysed, this is usually carried out by the processing or production team.
The second step in a Total Productive Maintenance (TPM) activity is to call a meeting involving key members of the maintenance and production teams such as plant supervisors and managers, maintenance and reliability engineers.
The third step involves analysing each stoppage, breakdown or incident of out of spec product and working through a root cause analysis framework to determine the causes of such incidents. This can be a time consuming event but the results can provide substantial improvements.
The fourth step involves assigning corrective actions to address the causes found in the previous step o members of the team.
The fifth and final step will be a follow up meeting to ensure the actions set out in the fourth step have been completed and to once again analyse the performance of the plant studied during this process. This can be done through repeating this process from the second step onwards.
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