If there are more than 1 production lines, I suggest calculating for each one which is the actual OEE. Which line has the highest profitability, which line must be prioritized? Now concentrate on that line only. Once you have gained experience with 5S and formed TPM teams on that line copy the methodology to each line.
I suggest making a list of all the issues you have observed in the production line. Do mark to what sources of loss do they belong to. Generally, there is no automatic time tracking system in place, so prepare a list for operators to classify and time stops.
Limit yourself to 15 reasons, otherwise things get confusing.
From your first analysis the main reasons must be clear. Discuss them with the operators and write them in the list.
Now the operator must fill out why and how long the machine stopped, and mark for which reason. Doing this over several shifts, gives you an overview. Now define which is the biggest loss. (this concerns stop losses). Also check the number of ejected packs, and the total, calculating the quality.
On a line there may be more than 1 operator. Define clearly who makes notes on which part of the line and combine these at the end of the shift. Make sure that you mark as a reason idling and forced stop and assure that the operators understand the difference.
The table down is an example but shows how you can define the events (the top section) and how to log manually (bottom section).
Now transfer the biggest losses in the following table. That helps to define the cause of the loss, the reason behind it, maintenance, procedure etc. and the possible solution. You may have to make a pareto analysis to define the possible causes behind a loss. Again, the following table is an example.
Cause 1: the primary reason why this loss occurs
Cause 2: the cause that leads to the cause described in Cause 1. (e.g. The problem of overload in the vibratory chutes is caused by a problem at the dribble board. This again may have different causes; here I list as cause 2 the lack of tracking of the cooling belts. It may have a 3rd cause, tracking of the oven belt or wear of the cooling belt etc. You can add more causes in order to get to the basic one. You may even add lines, as there can be several causes for one problem.
The cause and remedies are fictional and serve as examples.
Once you have an overview for the issues at hand, you must decide where to start. In that decision, several aspects must be considered.
The following table gives an overview of the pros and cons of different solutions. Go back to the loss/cause/remedy chart and mark which problem is easy to improve, which is a bottleneck, and which is the most problematic. There can be several of each kind.
|Easiest to improve||• Best opportunity for “quick win”
• More forgiving of limited TPM experience
• Less payback than improving constraint equipment
|Constraint / Bottleneck||• Immediately increases output
• Provides fastest payback
|• Working on critical asset as a trial project is a higher risk option
• May result in equipment being off-line more than desired as it is improved
|Most problematic||• Improving this equipment will be well supported by operators
• Solving well known problems will strengthen support for TPM project
|• Less payback than improving constraint equipment
• Unsolved problems are often unsolved for a reason – it may be challenging to get a good result
Source: Vorne Industries
As always, money is a key factor, so mark how much must be invested to solve the issue. Training is also an investment because it requires time of your personal, it requires preparation, teaching material. Make an estimate.
Using this classification of the possible solutions, add your estimate of the solution and the cost involved to the Loss/Cause/Remedy excel. Set your own limits for defining low, medium, and high cost, but define these dimensions so there is consistency.
Most important though measure the frequency this problem occurs and calculate the monetary cost of that loss. Based on that information make a pareto analysis, whereby the definition of the priorities is first the cost of the loss and second the cost of repair.
See also the other considerations below (low hanging fruits).
Consider what was discussed in chapter 2, work the line from the end backwards.
Based on this sheet and the biggest loss analysis, you can take decisions where to start, but take in account the following:
A solution may be a quickie that can be implemented immediately but one that will not last and does not solve the problem completely. There may be a solution that solves it completely but takes long and has a high cost to implement.
Once decided where to start, commence with 5S
Example of a shadow board. You will have to make this according to the tooling required for the specific job.
Clean up the place
Photo source: Pinterest.com
Such a checklist serves to check the machine at the start of a shift. It describes how the equipment is left by the earlier shift.
It must be signed by both operators, the one that leaves and the one that take over. You will have to develop the list according your situation.
Using such a checklist to make a 5S audit gives you a tool to check compliance. The audit will result in a score. The total score can be used to match different teams against each other and create incentives. This will help to make this an automatism for all personal.
Make the 5S visible for all; describe how to do and how NOT to do. Scores can be on this board too.
For Autonomous maintenance, start with Safety. Make sure that the electrical power can be cut before cleaning. The responsible operator must be the only person with the key, assuring no-one can restore electrical energy.
Cleaning is part of CIL standing for Clean, Inspect, Lubricate
Enable simple Inspection
Transparent covers or ones with a window allow operators to check the conditions of drives or other components inside.
With red and green marking make inspection easy.
Mark where machine components require greasing and for each greasing point indicate with a graphical mark which type of lubricant must be used.
Make a Plan with pictures showing all the greasing points.
We suggest making an excel table showing all the points the be greased and the type of lubricant to be used. It should show the dates when must be greased. This serves as a checklist marking the points greased.
Here an example of lubricant coding:
In the next article I will deal with quick change-over, SMED, center lining, examples of autonomous maintenance.
Leading image: By OpturaDesign/Shutterstock.com