Lean Manufacturing in Maintenance essentially comes from Total Productive Maintenance (TPM). It is a Japanese methodology that bases itself on effectiveness maximization through organizational involvement.
In this approach, all employees and levels of the organization support maintenance and reliability initiatives. The ideas behind TPM are fundamental to a lean process, including the 5S principle, autonomous and planned maintenance, and continuous improvement. Lean maintenance puts these philosophies into practice to minimize costs and increase the reliability of equipment and systems.
To understand the meaning of “lean maintenance”, we must first go through the definition of lean manufacturing processes. In simple terms, it means eliminating waste all across the production chain.
What Is Lean Manufacturing?
Lean Manufacturing is a philosophy that seeks to reduce the time between customer order and delivery by eliminating waste. It is a set of principles, concepts, and techniques to eliminate waste at all stages of the production chain.
The “lean” methodology is based on the Toyota Production System (TPS). The main goal here is to implement Continuous Improvement, thereby:
- Reducing costs
- Improving processes.
- Reducing reaction time.
- Improving customer service.
- Increasing quality.
- Reducing delivery time.
- Eliminating waste.
- Increasing productivity and profitability.
Waste Types in Lean Manufacturing
Lean Manufacturing focuses on creating a process without any unnecessary activities, and it does this by eliminating 7 different types of waste. Let’s go over at each of them briefly below:
- Overproduction: producing beyond existing orders, i.e. having inventory of semi-finished or finished products that still depend on orders from customers.
- Waiting time: situations where the production process suffers several interruptions due to various situations, such as: maintenance repairs, lack of materials, failures in setup processes, and other situations that may “delay” the continuity of the production cycle.
- Transportation: time spent transporting all the materials used in production, and the time spent between the stages of the production process from one location to another.
- Unnecessary processes: the means necessary to “make production happen”, where the use of unnecessary resources may occur. That is, more than necessary, inadequate tooling or lack of them, inspections that are not all necessary or prepared incorrectly, etc.
- Stock: due to overproduction, there is an accumulation of raw or in-process materials, or even finished products. And it will be necessary to create inventory, which implies an increase in activities such as transportation, storage, notes, accounting, traceability, generating unnecessary costs.
- Movement: any motion that is not necessary to complete a requirement during the process. This refers to moving around in search of tools, for example. It also relates to the layout of machines and equipment, and location of materials used during the production process.
- Defects: due to defective materials used or generated in the production process. Worst case scenario, the finished product is sent to the customer with defects and/or non-conformities. Unnecessary rework is generated and results in high costs.
The 5 Principles of Lean Manufacturing
The whole set of concepts and tools of the Lean Manufacturing methodology is based on 5 main principles.
- Value: what really adds value to a product or service defined by the customer who is willing to pay for it.
- Value chain: the set of actions required to produce a particular product or service. The steps to create value and discard what does not contribute.
- Continuous flow: making sure that production keeps up without interruptions and in rhythm with customer demand. The flow of processes becomes challenging but necessary.
- Demand-based system: produce what has actually been sold, i.e. production only starts when there are customer orders. 100% effectiveness in production cannot be achieved, but the efficiency of the implementation is directly linked to this index.
- Perfection: constantly working on continuous improvement, a mindset that needs to be present throughout the entire production chain.
What is Lean Maintenance?
Lean Maintenance is the application of lean techniques and tools in the maintenance process, with the aim of eliminating waste. Although this premise is natural to maintenance activities, management errors and lack of control can turn it into a source of waste.
The focus of Lean Maintenance is to increase the availability and reliability of machines, constantly seeking to raise productivity.
Check Out 5 Ways to Reduce Unplanned Downtime
How to Apply Principles of Lean Manufacturing in Maintenance
Lean Manufacturing in Maintenance is one of the key premises for a successful and productive environment.
Maintenance is strategic to various business segments, and should work to avoid waste. There are several methodologies that meet these needs, such as TPM – Total Productive Maintenance and RCM – Reliability-Centered Maintenance.
Both have great tools and concepts that support Lean Maintenance. It is up to maintenance managers to apply all the concepts of Lean Manufacturing based on the different types of waste.
Types of Waste in Lean Maintenance
- Inefficient and/or Unfocused Activities: without proper planning, maintenance team efforts may be focused on less priority tasks. This kind of waste can be avoided with efficient scheduling, focused on the correct management of available resources.
- Spare Parts – Shortage or Surplus: this is a major concern in maintenance management due to its high cost. The availability or shortage of critical items deserves the full attention of management. Waste can be found in costly parts and with low turnover, for example. The opposite can also be wasteful, if critical parts are unavailable at the time of repair, that can generate low asset availability.
- Manpower – Team and Skills: if the team doesn’t have the necessary skills to perform maintenance activities, orders can be poorly performed or the same task can be done twice – in other words, rework. Another problem would be to have a very small team that is unable to handle all the necessary activities. Or too many people adding costs and inefficiency to the process.
- Insufficient Information System: adequate maintenance management software is also necessary. The lack of an efficient system can lead to insufficient information and difficulties in decision-making. Forming a database is very important in order to generate reports and indicators.
- Misguided Strategies: the lack of appropriate strategies directly affects the availability of machinery and equipment. And even if you have the right strategies, you need to manage them well. Preventive maintenance must have an adequate plan for each type of asset and with appropriate intervals. A poorly designed preventive strategy becomes a problem that can generate high costs and little result. The various predictive maintenance techniques are undoubtedly a very effective strategy when well designed and managed. The entire sector can avoid unplanned equipment downtime.
- Inadequate Procedures: Just like in production sectors, maintenance needs processes and procedures to account for activities. If everyone works independently, without following those procedures, it’s harder to obtain satisfactory results. Maintenance needs work processes such as information registration, flow of work orders, problem solving, improvement processes, among others.
The application of Lean Maintenance can lead to significant benefits, such as reduced operating costs, increased asset availability, better use of labor, and greater efficiency of maintenance processes in general.
To implement Lean Maintenance, the solution begins in management, all the waste listed above can be solved with efficient management. Understanding each member of the team, promoting adequate working conditions, encouragement, and continuous training is the solution.