Coating Tech Slot Dies Process Troubleshooting Six Sigma Presentation June 2014
•Télécharger en tant que PPTX, PDF•
3 j'aime•6,348 vues
Learn about web technology and Six Sigma methodology in process trouble shooting. The presentation explains how to define, measure, analyze, improve and control (or uphold the changes) of your process. The examples included focus on the slot die coating process.
Recommandé
Contenu connexe
Tendances
Tendances (20)
En vedette
Similaire à Coating Tech Slot Dies Process Troubleshooting Six Sigma Presentation June 2014
Similaire à Coating Tech Slot Dies Process Troubleshooting Six Sigma Presentation June 2014 (20)
Plus de Coating Tech Slot Dies
Dernier
Dernier (20)
Coating Tech Slot Dies Process Troubleshooting Six Sigma Presentation June 2014
- 1. PROCESS TROUBLESHOOTING Web Technology and Six Sigma Methodology
- 2. Web Processes & Six Sigma Define Measure Analyze Improve Control
- 3. Six Sigma DMAIC DFSS 3.4 DPMO Doctrine: Continuous improvement is critical The process can be measured correctly Buy-in from all stakeholders for improvements ($ v management timeline)
- 4. Define Definitions Where do the defects come from? Goal & Entitlement Discrete plan – Continuous application Team membership
- 5. Define Define v Design Process map Owners v Changers
- 6. Measure Measure the correct things correctly Examples of variables for coating defects Web (tension, steering and substrate quality) Fluid delivery (pump variation) Coating head (angle of attack) Curing (method stability) Physics (roll diameters) “What gets measured gets done.”- Tom Peters
- 7. Measure Discrete (widget) v Continuous (web) Fluid Substrate Coating Head Curing Measurement systems
- 8. Coating Variables Fluid Downweb variation Flow meters Viscosity Mixers Contamination Air Entrapment Temperature control
- 9. Coating Variables Substrate Downweb & Crossweb variation Know what you are getting Surface energy Web cleaners Steering Tension Temperature control Static
- 10. Coating Variables Coating Head Crossweb variation Air entrainment Attack angle (positioning) Roll TIR “Coating window” Edge effects Temperature control
- 11. Coating Variables Curing Stability Temperature control Time requirement v Extent of cure Effect on substrate Method defects (drying, UV, eBeam, etc.)
- 12. Coating Variables Measurement Systems Incoming substrate Coating head Outgoing web Fluid Crossweb Downweb Machine chatter Continuous?
- 13. Analyze Cause-and-effect Statistics “On board” – Team management Roll example Root Cause "There are three kinds of lies: lies, damned lies and statistics.”- MarkTwain
- 14. Improve DOE Process journal Human element
- 15. Improve Input changes PET cut example RTY Hard band defect example
- 16. Control Statistical Process Control Continuous improvement
- 17. Summary Web Processes Variables Fluid Substrate Coating Head Curing Measurement systems
- 18. Summary Six Sigma Define Define v Design Measure Correct things correctly Analyze No wasted effort Improve DOE Control Continuous improvement
- 19. Thank you Images provided by Conquip, Inc. 11255 Pyrites Way Rancho Cordova, CA 95670 916.379.8200 sales@conquip.com www.conquip.com
Notes de l'éditeur
- Six Sigma is a quality control system utilized around the world for everything from discrete parts to organizational efficiency. The question is: How do you best utilize Six Sigma to reduce web defects and institute process controls? Originally designed for individual parts, Six Sigma methodology requires a unique approach when applied to a continuous web operation. Process troubleshooting in the Six Sigma world hinges on the ability to apply discrete measures to a continuous product. This presentation will walk through the considerations a manufacturing site should go through to reduce product defects and increase robust product design for a continuous web product.
- As a Certified Six Sigma Black Belt for 3M web coating applications, (Mark Miller) I have expertise in manufacturing processes and coating applications. One caveat is that my experience is almost exclusively slot die coating, so the examples will be for these type of applications. Examples will pull from coating experience at 3M and consulting for a variety of companies and be as varied as precision optical film coating and hot melt adhesive tape manufacturing. My audience background is unknown , so I will have to cover some basics, but we will quickly move onto detailed examples of web technology and the idiosyncrasies associated with continuous operations. Whether you know nothing or everything about Six Sigma, feel comfortable that the presentation will be easy to follow and provide valuable insight into process troubleshooting for web technologies. Think of the six sigma methodology as the scientific method and you should be good to go.
- Like the scientific method, Six Sigma follows a roadmap or thought structure that is stated as an awkward acronym DMAIC. Define the problem, Measure the problem, Analyze the problem, Improve and Control for continuously improved results. I will also discuss Design For Six Sigma from the product and process perspective. This simply means thinking ahead to reduce manufacturing and product issues ahead of time. Finally, I define Six Sigma simply as a mental methodology you can go thru to improve a process and/or product and eliminate defects. A Six Sigma presentation would not be complete without the explanation of the term itself: Six Sigma is derived from the standard deviation, a statistical analysis parameter and is defined implicitly as defect levels below 3.4 defects per million opportunities (DPMO). It is of course important that the defect and the opportunity are correctly defined or the measurement is useless. Six Sigma doctrine holds to : Continuous efforts to achieve stable and predictable process results (i.e., reduce process variation) are of vital importance to business success. Manufacturing and business processes have characteristics that can be measured, analyzed, improved and controlled. Achieving sustained quality improvement requires commitment from the entire organization, particularly from top-level management.
- OK, so let’s define the problem. In the world of Six Sigma it is important that a goal is defined and “entitlement” is understood. Entitlement is a stretch goal – what the subject matter experts feel the ultimate is (this may not even be the ultimate goal). For a web application this goal should have a continuous process focus, but a discrete product plan. What I mean is, the measurement (discussed later) needs to focus on improving the performance (reducing the defects) of the final product within the confines of the web process. The entitlement may require new equipment or modification to the existing equipment. As much as Six Sigma works you down the scientific method, it is important that the human side of the operation is understood. Emphasis on buy-in from the management is just as critical as the understanding from the operators as to why the project is being worked on. Team buy-in from the top down AND the bottom up are important in the Define stage of the six sigma project. In the past I have held one-on-one buy-in meetings with the controlling parties. This time is well spent. Never assume the project will work because people “do what they are told”.
- There are 2 main groups of projects: like I mentioned earlier, improving an existing process/product OR designing a new product/process. If we take an existing process, individuals who have been involved with this system can be tapped to identify where the weaknesses and strengths of the process are as applied to the product. For a new product on an existing line, the borders of the process and allowable raw materials need to be the constraints for the product. Ultimately, for a new product with an unidentified process, the world is wide open for the process (which may be a blessing or a curse). Either way, the process map needs to be drawn up. Basically this is a unit operations diagram with inputs and outputs, taking into account human interaction with equipment, raw material variations and measurement system limitations. Once this process map is established, it gives a talking point for the process improver to discuss details with the subject matter experts. This allows someone who is not emotionally tied to the process/product to identify areas of improvement.
- What should be measured? The key things to consider in measuring a web process is the final product use. A web product that is converted into first aid dressings (Band-Aids) that are small discrete objects is going to be measured differently than a web product that is converted into a television screen that is a large discrete object. The same analogy can be made for a roll of masking tape versus a wide roll of industrial tape. The difficulty in measuring a product that is in roll form is that it cannot be “fully” measured. In theory, each discrete widget can be measured for quality if the test is not destructive. Not so with a continuous web – this is where statistics comes in. We are not going to go into detail about how to statistically identify a reproducible product. We are going to talk about the major variables that typically are identified to reduce web coating defects. On this slide are some examples with ties from the equipment to the defect. A more comprehensive list will be presented later. At this stage we are interested in the major defects and after analyzing these and the accompanying raw materials and equip
- We are going to take the web technology (process operation) and break it down into the parts that add to the defects presented in a web coating process. By measuring the main variables, improvements can be made at these locations to reduce the defects and improve overall quality. The Unit Operations for a coating application include 1.Fluid and Fluid Delivery 2.Substrate and Substrate Delivery (tension and steering) 3.Coating Head (attack angle and roll TIR) 4.Curing (stability of environment and effect on product) 5.Measurement systems (online) In a web coating application it is important to be able to identify where the defect occurred. One simple example is to have idler rolls of different diameters grouped by sections throughout the process. Therefore, if you see a repeating defect, you can isolate the defect to the section of the repeating distance and the correlating diameter.
- To reach more detail, here are the items to consider in fluid flow- Pump type Flow meter use Viscosity info and sampling(use for simulation) Properly mixed (w/o air issues) Filtration Air elimination (ordering of trials) Maintain temp (hoses are important)
- What variables to consider in substrate analysis- What was received (have good upstream communication) Ability to treat surface(changes with storage) Contamination from manufacturer Enough to maintain (integration) Tension programs need to vary with substrate variation Termperaturemay play a part especially if trying to counter substrate variation Contamination “on the fly”
- What variables to consider in the coating head- Fluid distribution can be simulated prior to manufacturing Interfaces are the nameof the game Positioning of equipment repeatablyand accurately Interfaces RTY Find the edges of the window thru DOE always (w/ journal) Edge effects versus waste After the hose before the roll
- Details of the curing system- Various cure methods, each has different effects PM schedule to maintain stability of operation
- And even the measurement system itself- Chatter associated with non-obvious issues
- The analysis of the variables (causes) and the effect on the defects created is the next step. Once the subject matter experts have identified the variables to measure to improve product performance it is again time to get management on board or the project will fail. I don’t have time to go into detail for these team management issues, I will point out that the time to accurately measure the process may not be acceptable to other team members. An example is a roll issue that was identified on a project I was working on. The consumable backing rolls were made to order and had a limited lifespan for the coating process. Although this six sigma project took months to analyze, the root cause was identified as 1 of the 12 components utilized to formulate the roll. The main point of this step is to identify the root cause of the defect. We need to narrow the scope so the team can identify the unit op to work on. “No wasted effort.”
- This is the fun step! By sticking to the discipline of Six Sigma, our team has now defined a defect to reduce, determined how to correctly measure this so the end use customer will buy more and did analysis that everyone on the team bought into and the experiments will be justified. From my experience there are 2 types of experiments that need to be done: 1.Official designed experiments (DOE) 2.Process journals DOE allow the engineer to focus his/her energy on the identified variables that should have the biggest effect on the process defect. Those familiar with DOE will know that 5 variables are ideal. In a 2^(5-1) factorial design, all 5 variables can be studied with the amount of work typically applied to obtain the data for 3 variable research. Process journals allow previously unidentified variables or process changes that may occur during the improve phase to be documented. These unscheduled events can end up uncovering a new root cause or an unmeasured source of error.
- One example is a product that was being coated that the operators realized were varying by input substrate. The substrate that came from cut “A” needed to be steered more to the left and wrinkled accordingly. The substrate that came from cut “B” needed to be steered more to the right and wrinkled accordingly. When the operators kept a journal at the process line, identifying their observations, a review by the engineer helped identify these cuts and schedule the incoming material to reduce at line changes required. In the improve phase, a critical idea to keep in mind is RTY, or “Roll Throughput Yield.” RTY is defined as the combined variability of processes. The combined effect of poor variability can be huge in taking a defect from an non-noticeable defect to a substantial defect. As an example of RTY, I worked with a coater who had a coated product that discretely had no issues, it was within spec (existing as was changed after the project) for the discrete sample, but in roll form the roll stock had a hard band that made the finished roll unacceptable to the end customer. This hard band was a coating caliper variation that did not show according to the existing spec, but a combination of the quality control measures (online gauge) and the process journal pointed the engineer in the right direction.
- What does “control” mean? Initially it means that the goal has been met for process/product improvement and the changes need to be monitored/implemented to be maintained. The hardest part, speaking from experience is to make sure as process owners/operators/management the changes are understood and upheld. Therefore, it pays to have a brief description of the “why” behind these new control measures are included in the control sheet. Of course, we hope that the process is the best it can be, but this stage usually means a re-definition of what the new financial goal and subsequent process should entail. When it comes to these new process definitions, discussing the equipment limitations with the proper vendor is appropriate.
- The variables discussed in this presentation that should be considered when reducing defects and improving overall quality for a web coated product include- 1.Fluid –DW variation A. Fluid characteristics B. Pump C. Filters D. Hoses 2.Substrate –DW & CW variation A. Surface energy B. Tension C. Steering D. Static 3.Coating Head –CW variation A. Interfaces Rule (RTY) B. Process window 4.Curing -stability A. Fluid reaction B. Substrate reaction 5.Measurement systems–discrete map of continuous product
- Six sigma is the template I utilized to approach process troubleshooting. To highlight the main points from this webinar: 1.Define A. Define a measureable goal B. “buy-in” 2.Measure A. Verify measurement capability B. Narrow the unit ops 3.Analyze A. Cause and effect to B. Root cause 4.Improve A. Experimentation B. Journal 5.Control A. Next steps (entitlement) B. Improve webs (over widgets) The goal of this presentation was to layout the six sigma methodology and identify the important differences when you consider webs over widgets.
- I want to thank Conquip, Inc. a custom web equipment manufacturing company for providing the images for this Webinar. Please feel free to contact them if you are ready to move onto “entitlement” for any of your projects.
- I appreciate you taking the time to be a part of this presentation. If you have any questions or comments, I welcome any feedback at my company’s email or phone. Coating Tech is a slot die manufacturing company and coating consulting firm providing precision manufactured slot dies, exceptional process engineering and on-site service to a wide variety of clients such as hot melt, battery, solar and optical coating companies. Coating Tech strives to develop and maintain a long lasting relationship with our clients based on exceptional service in the field and developing operational solutions to meet the clients’ needs. When it comes to understanding and implementing slot die coating technology, Coating Tech provides the experience and knowledge to insure a project’s success. With decades of experience in a broad product range, Coating Tech provides a breadth of process knowledge and the depth of slot die coating experience. Thank you.