Production Troubleshooting - A251
Production Troubleshooting | |
---|---|
Practice article | |
Document Type | Article |
Document Identifier | 251 |
MSTE workflow | Troubleshooting |
Prerequisites |
Overview[edit | edit source]
Is your manufacturing process failing to meet requirements? This section of the KPC will help you troubleshoot your process and factory. It contains common troubleshooting questions which link out to pages explaining how to conduct typical troubleshooting activities such as troubleshooting the quality of a part with variable thicknesses or the rate of a thermal transformation equipment. The troubleshooting questions are grouped according to the manufacturing outcomes to be improved: cost, rate, and quality. A more structured approach to the troubleshooting process is also introduced below and illustrated in a flowchart. This structured approach will guide you methodically through three fundamental troubleshooting steps: diagnosis, remediation and validation. The diagnosis step consists of systematically identifying the root cause(s) of the problem, and more specifically the malfunctioning process step(s) and manufacturing object(s) or physical asset(s): material, part shape, tooling & consumables, and equipment. When part quality is the issue, the diagnosis step is based on a taxonomic approach which classifies the large number of sources of variability and defect types in composites manufacturing. In the following remediation step, the deficient step(s) and manufacturing objects are optimized to meet specifications or to increase their robustness by addressing any source of variability.
Troubleshooting Activities[edit | edit source]
Thermal Management Outcomes[edit | edit source]
- I am trying to transition basic tooling styles, such as from composite to steel tooling, or vice versa, with everything else the same, to lower cost but am experiencing new cure quality issues. Visit troubleshooting when changing production tooling material.
- I am finally making good quality parts but am not meeting my production rate and would like to cure them faster to make better use of my capital equipment. Visit troubleshooting throughput during thermal transformation.
- I am making good quality parts in one cure vessel and am considering moving to another, seemingly similar, vessel where I will use the same cure program. How do I ensure that my part quality does not drop? Visit maintaining part quality when changing curing equipment.
- I am having difficulty establishing cure families for a given cure vessel where all the parts in the family can be cured in a reasonable amount of time. Visit troubleshooting cure families for batch loads during thermal transformation to meet rate or quality requirements.
- I am attempting to transition tooling styles, from autoclave to press cure, to increase production rate and am experiencing new quality problems. Visit transitioning tooling styles between different thermal transformation equipment.
- I am making good quality parts in one cure vessel but in another, seemingly similar, vessel part quality has dropped or become inconsistent, despite using the same cure program. Visit troubleshooting quality issues during cure for different equipment types.
- I am trying to make thicker parts than I have before with a given resin system and am experiencing large exotherms and associated part quality issues. Visit troubleshooting scale-up issues from thin to thick parts.
Material Deposition Outcomes[edit | edit source]
- I have used a given resin system to cure a wide variety of good quality parts but am looking at switching reinforcement styles (such as to a tightly woven reinforcement). How do I ensure that I can continue to make good quality parts with the same cure cycle? Visit maintaining equivalency during cure for different fibre architectures.
- I have used a given prepreg resin system to cure a wide variety of good quality parts, but having switched reinforcement types to lower cost, I can no longer make good quality parts with the same cure cycle. Visit troubleshooting part quality during cure when changing the reinforcement.
- I am making a part containing regions with a wide range of thicknesses and am having issues getting good part quality in all part regions at the same time. Visit troubleshooting part quality for variable thickness parts.
- I have been successful in making smaller parts but in trying to cure larger ones I am experiencing new quality issues. Visit troubleshooting scaling issues from small to large parts.
- I have made lots of good quality flat panels during qualification but my parts, cured in the same way (and perhaps using the same cure program), are of poor quality. Visit troubleshooting scaling-up issues from coupons to parts.
Flow and Consolidation Outcomes[edit | edit source]
- I have defined a baseline cure cycle leading to a satisfactory level of consolidation but am looking at moving to a different one. How do I ensure that the amount of resin flow of my new cure cycle is neither too little nor too much when compared to the baseline cure cycle? Visit ensuring appropriate resin flow and part consolidation for a new cure cycle.
- I am experienced in making relatively complex parts with standard tooling strategies but am looking at using a new resin chemistry. How do I ensure that that I get adequate flow and consolidation, neither excessive nor insufficient, with a new resin system? Visit ensuring appropriate resin flow and part consolidation for a new material.
- I am experiencing too much resin flow during my cure cycle and would like less. Visit troubleshooting resin flow and part consolidation for a cure cycle.
- My tooling for a given type of part is the same style as used for similar parts around the world but the prepreg system chosen has a different resin chemistry compared to that used for every other part like this. The tools do not function in the same way (excessive flow) and do not provide good quality parts. Visit troubleshooting tooling to achieve part quality.
Assembly Outcomes[edit | edit source]
Troubleshooting Process[edit | edit source]
Diagnose[edit | edit source]
Coming soon.
Remediate[edit | edit source]
Coming soon.
Validate[edit | edit source]
Coming soon.
Explore this area further
- Production Troubleshooting - A251
- Practice for troubleshooting a Light RTM step - P107
- Troubleshooting scale-up issues from thin to thick parts - P140
- Troubleshooting quality issues during cure for different equipment types - P141
- Ensuring appropriate resin flow and part consolidation for a new cure cycle - P119
- Troubleshooting scaling-up issues from coupons to parts - P134
- Troubleshooting scaling issues from small to large parts - P136
- Ensuring appropriate resin flow and part consolidation for a new material - P120
- Transitioning tooling styles between different thermal transformation equipment - P139
- Troubleshooting when changing production tooling material - P130
- Troubleshooting a cure cycle for improved production rates - P132
- Troubleshooting tooling to achieve part quality - P142
- Maintaining part quality when changing curing equipment - P122
- Troubleshooting part quality during cure when changing the reinforcement - P131
About | Help |
Welcome
Welcome to the CKN Knowledge in Practice Centre (KPC). The KPC is a resource for learning and applying scientific knowledge to the practice of composites manufacturing. As you navigate around the KPC, refer back to the information on this right-hand pane as a resource for understanding the intricacies of composites processing and why the KPC is laid out in the way that it is. The following video explains the KPC approach:
Understanding Composites Processing
The Knowledge in Practice Centre (KPC) is centered around a structured method of thinking about composite material manufacturing. From the top down, the heirarchy consists of:
- The factory
- Factory cells and/or the factory layout
- Process steps (embodied in the factory process flow) consisting of:
The way that the material, shape, tooling & consumables and equipment (abbreviated as MSTE) interact with each other during a process step is critical to the outcome of the manufacturing step, and ultimately critical to the quality of the finished part. The interactions between MSTE during a process step can be numerous and complex, but the Knowledge in Practice Centre aims to make you aware of these interactions, understand how one parameter affects another, and understand how to analyze the problem using a systems based approach. Using this approach, the factory can then be developed with a complete understanding and control of all interactions.
Interrelationship of Function, Shape, Material & Process
Design for manufacturing is critical to ensuring the producibility of a part. Trouble arises when it is considered too late or not at all in the design process. Conversely, process design (controlling the interactions between shape, material, tooling & consumables and equipment to achieve a desired outcome) must always consider the shape and material of the part. Ashby has developed and popularized the approach linking design (function) to the choice of material and shape, which influence the process selected and vice versa, as shown below:
Within the Knowledge in Practice Centre the same methodology is applied but the process is more fully defined by also explicitly calling out the equipment and tooling & consumables. Note that in common usage, a process which consists of many steps can be arbitrarily defined by just one step, e.g. "spray-up". Though convenient, this can be misleading.
Workflows
The KPC's Practice and Case Study volumes consist of three types of workflows:
- Development - Analyzing the interactions between MSTE in the process steps to make decisions on processing parameters and understanding how the process steps and factory cells fit within the factory.
- Troubleshooting - Guiding you to possible causes of processing issues affecting either cost, rate or quality and directing you to the most appropriate development workflow to improve the process
- Optimization - An expansion on the development workflows where a larger number of options are considered to achieve the best mixture of cost, rate & quality for your application.