SDD: Total Productive Maintenance Rev 1: 2013 November 10. Page 1 of 22

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2 Page 2 of 22 Contents Introduction... 3 Step 2 Eliminating the sources of contamination... 4 Aim of step Preventing leaking, spilling, spraying and scattering of:... 5 Lubricants... 5 Improving the accessibility of places that are hard to:... 5 Contamination analysis sheet... 9 Step 2 Eliminating the sources of contamination Machine What can be observed from Figure 7? Aim of Machine Mapping: Who is responsible? The importance of eliminating the sources of contamination Obstacles to eliminating the sources of contamination Steps to countermeasure contamination Detecting abnormalities - 5 senses Monthly Cleaning, Inspection and Lubrication Chart Cleaning Time Record Sheet Aim: Who is responsible for the document? Table of Figures... 22

3 Page 3 of 22 Introduction Management and operators should by now be familiar with Autonomous Maintenance Step 0 and 1 which is part of the TPM approach covering 8 Pillars. The next session will focus on Autonomous Maintenance Step 2 and 3 and will go into more detail on how to approach and implement these steps successfully. Operators will carry on with what have been learned during Step 0 and 1 to ensure the success of the next steps. It is important not to try and rush the implementation of these steps as it is very easy to skip vital procedures or documentation that forms part of the process. That is why there are a set methodology to follow for each and every step to ensure the successful implementation of TPM. Figure 1: Stepped Approach to TPM implementation for Autonomous Maintenance

4 Page 4 of 22 Step 2 Eliminating the sources of contamination Before starting with Autonomous Maintenance Step 2, Step 0 and 1 must be implemented properly and operators must understand what are expected from them. The best method of ensuring success is by conducting weekly audits to get operators into a habit of doing the right thing automatically. Aim of step 2 This step is designed to cut off sources of dust and stains, to improve places where scattering prevention, cleaning and oiling are difficult and to enable cleaning and oiling within the target time. Operators should strengthen their ability to improve equipment and gain confidence to pursue even higher level improvements. When referring to sources of contamination it includes everything identified during step 1. In step 2 the focus is on eliminating the sources of contamination. Operators maintain the equipment after Step 1 training and implementation, but quite often the task just becomes intolerable and very time consuming. That is why step 2 is important to reduce the amount of time it takes for an operator to clean, inspect and lubricate.

5 Page 5 of 22 We can only achieve a reduction in time by implementing the following methods: Preventing leaking, spilling, spraying and scattering of: Products Lubricants Hydraulic fluids Powders Vapours Other process materials and Improving the accessibility of places that are hard to: Clean Check Lubricate Tighten Operate Adjust How can leaking, spilling, spraying and scattering be prevented? Answer: Implementing preventative measures to avoid material from leaking, spilling, spraying and scattering. These measures can include regular inspection of pipes, fittings, pumps and reservoirs.

6 Page 6 of 22 Figure 2 below show an operator busy inspecting his equipment. Figure 2: Operator inspects equipment Attaching covers or guards to machines where material are likely to spray or scatter. Guards can range from a simple plug to a larger metal sheet. Drip trays can be used in conjunction with guards to avoid oil, cutting fluid and other liquids from dripping onto the floor. Figure 3 below show a simple plug to eliminate debris from getting into the hole. This simple measure save a large amount of time, especially when there are multiple holes on a machine where dust can gather and collect.

7 Page 7 of 22 Figure 3: Example of a plug to eliminate contamination Transparent cover, normally closed. Figure 4: Machine with guard attached

8 Page 8 of 22 Providing and using the correct and proper tools to operate and maintain the best machine condition. Operators tend to use tools that are readily available, if correct tools are not provided or close to the point of use. An example is an operator using a screwdriver to make a hole, instead of a punch or using a big wrench as a hammer. Figure 4 below illustrates some tools and the appropriate warning to not use a tool if it is not suitable for the task at hand.. Figure 5: Correct tools for the work required Any improvement possible must be done to ensure high employee morale are promoted and the final product reach the customer faster at a quality level that satisfies the needs of such a customer.

9 Page 9 of 22 Contamination analysis sheet Zone/Area Equipment Name Preceding Process Control No Rev Moulding HWS Sand plant Date Contamination/Obstr uction Description Composition Autonomous Maintenance Step 2 Contamination Analysis Sheet Area on equipment where found Entire plant Source of contamination Hard to ( Yes No X ) Clean Lubricate Inspect Access Instance of occurrence Kaizen control Dust Bentonite and coal dust Moulding operation during casting X X During operation of the moulding machines 001 Figure 6: Contamination Analysis example Figure 6 is an example of a sheet that is used when a source of contamination have been identified and also to classify into which category of TICL it belongs. The sheet consist of a number of columns and rows that need to be completed. Each section will be explained below. Zone/Area: This section is where the area or zone on the machine are where the contamination occur. Equipment Name: What is the name of the piece of equipment or machine? Preceding Process: What process immediately precedes the current process? Control Number: That is a number that follows on from the previous contamination analysis sheet.

10 Page 10 of 22 Revision: What is the revision number on that specific piece of equipment? Date: Date the contamination was identified and classified. Contamination Description: What type of contamination have been encountered. Composition: Does the contamination consist of more than one type of material. Area on equipment where found: Picture or description of where the contamination occurs. Source of Contamination: What is the source of the contamination? The operation or process where it starts. Hard to columns: Indicate using a green tick for yes and a red cross for no into which category of TICL the contamination falls. Instance of Occurrence: When does the contamination take place? During which operation or when what actions are performed? Kaizen Control: Are there a Kaizen sheet that is linked to the contamination?

11 Page 11 of 22 Step 2 Eliminating the sources of contamination Machine A B Figure 7: Machine mapping example C What can be observed from Figure 7? The areas marked A, B and C indicates a number of chain driven gears and a screw mechanism. These areas are visible because the metal covers are removed. Under normal operating conditions the covers would be in place and it would be extremely difficult and time consuming to inspect, clean, tighten and lubricate those working parts of the machine. Aim of Machine Mapping: The aim of a machine mapping exercise are to identify all the areas on the machine that are hard to clean, inspect, lubricate and tighten.

12 Page 12 of 22 Who is responsible? Machine mapping are performed as a group to identify these difficult areas that have been observed in Figure 7. An experienced engineer should be chosen as the group leader to provide guidance on what needs to be done. Machine mapping can be used in conjunction with a red tag exercise to identify problems and sources of contamination. Access must be simplified to areas of the machine that needs to be inspected, cleaned, tightened and lubricated. This can be achieved by implementing some of the following solutions: Hard guarding (wire mesh, etc.) is needed for safety, in many applications to protect the operator or maintenance personnel from parts of the machine that are moving, rotating, etc. They can be painted many colours, including safety yellow, but as can be seen from figure 8 below it makes inspection extremely difficult. Figure 8: Before

13 Page 13 of 22 A simple and fast sollution is painting the mesh black. This would allow the operator to see through the mesh as per figure 9 below saving time and effort. Figure 9: Black mesh simplify inspection See through machine guards to eliminate swarf and coolant spraying is an effective measure to ensure easy inspection and a reduction of cleaning time, because the contamination are controlled and localised at a certain area. Figure 10 below is an example of a see through machine guard. Figure 10: Clear machine guards

14 Page 14 of 22 The importance of eliminating the sources of contamination Sources of contamination must be eliminated because contaminants hide machine defects that causes quality defects and breakdowns. Common causes of contamination include: Fibres from clothing and cloths (hair) Excessive dust & dirt. Water & coolant leaks. Spillage due to missing or damaged guards, shields or chutes. Damaged extraction. Incorrect swarf removal. Incorrect design of equipment. Work method. Incorrect tools/equipment to do the job Some items are generated unavoidably due to the principles of processing and cannot be stopped at the source. The following steps should be taken: Reduce absolute volume Limit the volume of releasing agent Limit the volume of coolant used Reduce cutting margins Cut scattering Prevent scattering through minimum coverage of the relevant location.

15 Page 15 of 22 Obstacles to eliminating the sources of contamination Although the harmful effects of contamination are widespread, often little are done to reduce the sources: Failure to apply a problem solving technique to contamination sources Operator and management knowledge of the equipment basic conditions Lack of understanding of the process Lack of knowledge of the correct operating standards of the equipment (lubrication levels, pressure etc) No system to identify abnormalities (Daily tagging and TICL) Most companies employ the use of ready-made machines, because custom build equipment are very expensive. The reality is that large amounts of time, effort and money can be saved by making practical modifications to equipment to simplify cleaning and basic maintenance. Steps to countermeasure contamination The first step is to accurately determine the nature of contamination. How and where are the contamination generated? A why-why analyses can be used if the cause are difficult to determine. The next step is to gather quantitative data(kg s, litres, etc.) on the volume of leaks, spills and other contamination (this helps operators understand the importance of measurement).

16 Page 16 of 22 An oil leak for instance might look insignificant, but if the amount of lost oil are measured and can be financially quantified, it can help the operator understand how much money can be saved by identifying and reporting leaks. Filter material to reduce dust. Figure 11: Pump with filter Figure 12: T-slots contamination eliminated T slots filled in with plastic covers saves a 3 hour cleaning operation.

17 Page 17 of 22 Detecting abnormalities - 5 senses Use the 5 senses, sight, sound, touch, smell and taste to identify abnormalities. Operators should be trained by maintenance to identify these abnormalities. Figure 11 below indicates how the 5 senses can be utilised. Figure 13: The 5 Senses

18 Page 18 of 22 Figure 14: Inspection stickers Figure 14 above is an example of inspection stickers that can be used to attach to a certain part of the machine or a piece of equipment to assist the operator in using the senses effectively in identifying abnormalities. Any combination and number of inspection stickers can be utilsed, depending on the type of equipment. Certain types of equipment could have more than one sticker like an electric pump can have a sight, smell and hearing sticker. Look for smoke, smell a burning smell or hear a noise could all be indicators

19 Page 19 of 22 Monthly Cleaning, Inspection and Lubrication Chart Figure 15: Graph indicating reduction in time Figure 15 is a simple graph to indicate the reduction in cleaning, inspection and lubrication time after Step 2 of Autonomous Maintenance have been implemented. Team leaders must be able to measure the time it takes operators to do TICL actions. Pro-active measures must be implemented to ensure that the TICL times are reduced. Monthly awards for the cleanest machine or workstation can be a good measure to encourage operators to clean the equipment thoroughly. Making continuous improvements and training of operators ensure that TICL time are reduced more and more each month.

20 Page 20 of 22 Step 1 Step 2 Step 3 Time (sec) % Improvement 0% 26% 23% 500 CLEANING TIME REDUCTION SUMMARY SHEET Cleaning Time Reduction Table TPM IMPACT STEP % % % % Improvement Time (sec) Step 1 Step 2 Step 3 Person Responsible Team Leader Team Leader Signature TPM Champion Signature Approval Date Reference Number Figure 16: Cleaning Time Record Sheet

21 Page 21 of 22 Cleaning Time Record Sheet Aim: The aim of the cleaning time record sheet is to track the cleaning times on the machines as a company moves from Step 1 to Step 3 of Autonomous Maintenance to determine if there are any reduction in the amount of time it takes to perform the TICL actions. Who is responsible for the document? Answer: The team leader is responsible to generate the information that are required to complete the form and to ensure sustainability. The team leader should receive training regarding time study if required to ensure the accuracy of the sheet. The TPM champion and team leader should also sign the document to acknowledge that they agree with the times recorded for cleaning. The team leader must ensure that the cleaning functions are timed and recorded regularly to guarantee an accurate document. The frequency should be daily during the kick off at each Autonomous Maintenance step and can be gradually reduced to once a week if the operators are able to show a higher level of understanding regarding the cleaning functions.

22 Page 22 of 22 Table of Figures Figure 1: Stepped Approach to TPM implementation for Autonomous Maintenance... 3 Figure 2: Operator inspects equipment... 6 Figure 3: Example of a plug to eliminate contamination... 7 Figure 4: Machine with guard attached... 7 Figure 5: Correct tools for the work required... 8 Figure 6: Contamination Analysis example... 9 Figure 7: Machine mapping example Figure 8: Before Figure 9: Black mesh simplify inspection Figure 10: Clear machine guards Figure 11: Pump with filter Figure 12: T-slots contamination eliminated Figure 13: The 5 Senses Figure 14: Inspection stickers Figure 15: Graph indicating reduction in time Figure 16: Cleaning Time Record Sheet... 20