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Autonomous maintenance is another term used when operating personnel are responsible for performing minor maintenance tasks. You may have heard the terms Total Productive Maintenance (TPM), Operator Essential Care, Operator-Based Maintenance, etc., but at the end of the day they all mean the same thing.

Autonomous maintenance can be implemented in many ways. We use the terms autonomous maintenance (AM) and user-based reliability (OBR) interchangeably here.

Involving operators in reliability is technically very simple, but it can be very challenging from a people perspective. This means that it is easy to work out what should be done and how to do it, but in many cases it can be almost impossible to get people to do the tasks. It is therefore worth spending a considerable amount of thinking time on the problem: "How do we as a company get people to do what we want them to do in terms of equipment maintenance?". The answer to this question will vary from country to country, industry to industry and local culture to local culture, but we (IDCON) will share some of our experiences.

"People don't mind change, but they mind being changed by others."

So one of the basic concepts of AM/OBR deployment is "participation". The level of participation needs to be considered before starting an OBR implementation, because the more people are involved, the longer it takes to decide what and how to do something. At the same time, greater participation increases ownership and acceptance.

As a leader, you need to decide when and to what extent to involve people in order to achieve the right balance. In general, leaders should make decisions about what is the right thing to do. For example, management should decide on the scope of the programme and the outcomes they want from the programme, while smaller groups can be tasked with figuring out how to do certain tasks, many people can help build the information in the work system once the design is done.

What will this work system look like when it is finished?

Before dividing people into tasks, it is important to paint a picture of what the finished product will look like. If you, as a leader, don't paint a clear picture of what AM/OBR will look like when it is complete, how can you expect your organization to move in the right direction? The sad truth is that most managers just say they want operations to take over the maintenance tasks, and everyone comes up with their own version of what it looks like. Below are things to consider and questions to ask as you begin to develop your AM programme:

#1 Define exactly what tasks you want the functions to do and what they currently don't do, or are doing but need to improve.

• Detailed equipment checks
• Equipment cleaning (how detailed)
• Running equipment at maximum speed, maximum reliability or maximum throughput
• Whether minor maintenance tasks are carried out, if so what exactly
• Whether problem solving and root cause analysis is led or participated in
• Whether only hourly workers are needed or whether involvement of paid functions is also required
• Should operations management improve reliability through better joint prioritization of maintenance work and joint scheduling with maintenance?

#2 Determine whether operators should have documented inspection routes and how inspections are performed.

• How detailed should inspections be?
• Should they have handheld devices (tablets, smartphones, etc.) to track problems and measurements?
• What inspection tools are needed?
• Who will be responsible for managing and cleaning up inspection routes to ensure they get done?
• Who will carry out the inspections and for how long? Does it vary by shift and task?

#3 What training and who needs to be trained?

• Are operations supervisors and managers trained to operate and inspect equipment?
• What training materials, training modules or courses are needed? Or do you assume that operators understand how pumps, motors, regulators and hydraulics work and what signs of failure these parts show?

#4 What happens when equipment is installed or removed?

• Who is responsible for updating operators' routes?
• Who is responsible for updating inspection instructions?
• There are, of course, many more questions, but by answering questions like the ones above, you will begin to paint a picture for your organization of what the system looks like.

Don't forget communication

Once the picture is painted, don't forget to communicate this future state to the organisation. Many organisations do not have effective communication channels. Typical communication is that top management communicates to middle management, and then it is assumed that middle management will spread it to lower management and so on. Both the content and the scope of the message are almost always poorly communicated. Try to ensure that the vision for the future is communicated clearly and professionally. Read more about OEE and benchmarking maintenance costs.

Implementation plan

The implementation plan does not describe what the final product will look like. The implementation plan describes the tasks needed to achieve the objective. Most implementation plans usually consist of many small tasks, I have outlined in this article some important tasks to consider.

A simple but structured documentation process is needed. There is not enough space in this article to explain the whole documentation process, so we have decided to list a few key points.

Have a logical approach to your maintenance method. Methods include Operate to breakdown Fixed Time Maintenance Condition Based Maintenance Ensure that inspection frequency is based on the estimated Failure Development Period (FDP) and not on criticality.

Use standards

Use standards for standard components. For example, a typical air cylinder is inspected 99% of the time in the same way regardless of location or application. The same is true for most components such as pumps, motors, filters, switches and others. Set points such as temperatures and pressures may vary, but the same point is measured.

Explain to inspectors how and why the inspection is being carried out. Our condition monitoring standard is designed to do this for you. You can download an example from our website: AC motor and coupling wheel.

Do not use Reliability Centered Maintenance (RCM) to determine each individual inspection. Use RCM when it is necessary for safety, when the system is complex, or when you want to train people in reliability theory. RCM is too cumbersome and overwhelming to determine the basic inspections for the entire site.

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Choose logical inspection routes

Inspection routes should include all equipment in a logical walking order. You should not do a route with only pumps, for example. If you do it component by component, the operator will have to walk the same area many times. Once pumps, once valves, once hydraulics, once piping, once tanks, once regulators, once vacuum pumps, etc. An operator never walks an area multiple times, so if you don't mix multiple equipment types in one trip, you will miss many critical parts and end up doing only motor inspections or only valve inspections.

Why use keywords in inspections?

We have found it useful to base operator inspections on standard component instructions. Each instruction consists of several keywords. A standard instruction is what the inspector carries with him in the field on paper or on a laptop. For example, an electric motor standard inspection may contain the following keywords: ventilation, detailed cleaning, water/humidity, motor base, electrical lubrication, temperature, noise and vibration.

The keywords are for memory refreshment only, not as instructions. If the inspector does not know how or why to do the inspection, he refers to the CMS. The CMS explains exactly how and why each inspection is carried out. The CMS can be available in a booklet in the inspection room or other public area, or they can be stored as PDF files on a shared server.

What about measuring points?

We believe that the general rule is to collect only the measurement points that are used. It is common for factories to collect as many measurement points as possible for each component. When the AM system is started, no one ever looks at the data. Do not collect more points than the plant can handle and has time to analyse. Why not start with 25 measurement points in each area and see if the data is used. If they do, add more data points. A good way to kill the AM/OBR process is to ignore the fault reports and the data collected.

What about resources?

Address resource issues before implementing an OBR programme. Before starting any AM process, you need to be aware of what is happening to resources and costs. The process will save you money, increase production efficiency (through reliable equipment) and reduce your workload in the long run, but in the short run it can do the opposite.

Why? By logical deduction, the maintenance backlog increases when the AM system is started because more problems are found than before. It costs money to perform maintenance work. Once the backlog is dealt with, the reliability of the equipment starts to improve (assuming that the prioritisation is done correctly). As reliability starts to improve, costs will fall because the plant will make fewer repairs, use fewer parts and have fewer interruptions to production schedules.

Getting management to commit to the programme

Plant and company management need to understand the basics of a condition monitoring programme. This applies to all inspections: PM, OBR, vibration, IR, ultrasonic, electrical, loop inspections of instrumentation, etc. Here are some discussion points and decisions that need to be supported by the facility and company management:

- The backlog of repair work will increase initially if the AM programme is implemented correctly.

- Maintenance workload will temporarily increase.

How will the plant cope? There are five options: improve efficiency through better planning and scheduling, overtime, use contractors, temporarily move people to the area, or don't do it and keep it as a backlog.

Equipment costs money to repair, so improving reliability requires up-front investment. To cost-effectively manage the maintenance backlog, a facility needs good planning and scheduling procedures.

Therefore, if the planning and scheduling process is not efficient, investment in planning and scheduling is needed. If your facility needs to improve planning and scheduling, we have options to help train your team, including self-paced training.

Improving equipment inspections

Detailed inspections require the right person with the right mindset, attitude and training. Most industrial organisations have some form of inspection programme, but unfortunately inspections are often ineffective.

There are many reasons why inspections are often ineffective. One reason, however, is that inspections are not detailed enough to find problems. Many inspectors simply walk past the equipment to make sure it wasn't stolen last night, and if they are in a good mood, they may make sure it is running smoothly.

To achieve an effective OBR system, operators need to be trained, both in theory and in practice. The core of a good OBR system is that operators understand the equipment. Below are some examples where a lack of knowledge of controls and components may be evident:

Example 1: Pump and motor coupling assembly in a paper mill.

This paper mill had an operator inspection system in place, which means that the operator should have checked it. I checked this unit intermittently throughout the week and it looked pretty much the same. Some issues should have come up immediately when an experienced inspector looked at this machine.

An experienced inspector would have noticed:

- I can't see the cables very well, so I can't check their condition.

- I cannot take the stroboscope to the connection because the inspection ports are covered.

- The motor runs hotter than necessary because it is covered with dirt.

- I can't see the oil level in the pump.

- The pump's drain plug is probably clogged.

- The breather tube is just a "goose neck" breather tube that is letting dirty air into the oil

- I wonder if the engine has jack bolts to allow for precise alignment?

- There is no flow meter or inlet or outlet pressure gauges on the pump, how would I know if it is running at the correct BEP?

- There are no locations or connections for vibration and temperature readings, I wonder where the previous guy took the readings so I could compare readings.

Example 2: Refinery engine lift bolt (push bolt).

Here's a close-up of the lift bolt on the engine stand. What would an experienced inspector see? This photo was taken in the southern United States in March.

An experienced inspector would notice:

- The bolt is touching the chassis. As the climate warms, the bolt lengthens due to thermal expansion and pushes the engine off line. The bolt needs to be backed off.

- Great, there's a jackbolt so we can align it well, but I wonder why they don't buy them with the jackbolt originally, as it would be much cheaper than putting them in after installation?

Example 3: Solenoid valve in a food processing plant.

The picture shows a typical solenoid valve in a hydraulic system. An inexperienced inspector might just look at it and make sure that the valve is installed and that the electrical cable is intact.
An experienced inspector would do this:

- Measure the coil temperature, knowing that if the valve sticks internally, the coil will often heat up as it tries to move the stuck valve.

- Listen to the whirring sound of the solenoid. The whirring noise occurs when the solenoid tries to move the valve several times.

- Make sure there are no leaks, detecting leaks can cause performance problems and cause additional heat.

Example 4: Pneumatic regulator in a surface mine.

The picture illustrates a pneumatic regulator that has been in use for some time. Most inspectors would not look at the device at all because mechanics consider it part of instrumentation, while instrumentation technicians rarely do physical inspections of the equipment.

An experienced mechanic would:

- He would put his hand in front of the leak hole and check for air leaking from the leak hole. If he feels air, he knows that the membrane inside the device is broken.

These four simple examples are just to illustrate the difference between walking past equipment and understanding how to inspect it. As operations and maintenance managers, we should not just hand people a list of 40 equipment numbers and assume that they know and are prepared to inspect the equipment correctly.

Text: Torbjörn Idhammar, Managing Director, Idcon Inc | Images:  Idcon, Shutterstock