Using checklists both for job preparation and during the manufacturing process can help achieve required levels of quality.
Executive Director, Center for Manufacturing Systems, New Jersey Institute of Technology
As part of their overall quality management programs, many companies use checklists within their processes to make sure they are achieving required levels of quality. These quality checklists can aid employees in both preparation for and performance during a job by providing a structured means for completing tasks needed to achieve a successful result.
For job preparation, quality checklists specify key information about the product and every-
thing needed in the manufacturing process. Verifying (with a check mark) completion of each
preparation-related activity can result in fewer wasted hours during manufacturing. Typically, the following information is included in the job preparation section of the quality checklist:
• Details about the product. This information can be found on routers, work orders, blueprints, process sheets or any documentation that is used to manufacture products in the facility. These details must be checked simply to ensure the employee understands exactly what has to be made, what the product should be made from (raw material or components), how it should be made, how many to make, when the product is needed and so forth.
• Tooling and equipment. Special tools and equipment needed to manufacture the product should also appear on the checklist. The focus should be on anything that has to be brought into the work center to complete the job or, in other words, anything that could cause the job to be delayed if not available. Likewise, if any of the special tooling or equipment requires prepping, such as dressing a grinding wheel, loading fasteners into a power tool or calibrating a tester, it needs to be included here.
• Material. All material or components used should be listed, preferably with an identification number (if available) and description. Just like with tooling and equipment, if the material needs to be prepped, such as pointing or cutting down bars, shearing sheets to a certain size, or heating or cooling components, it should be indicated here.
• Supplies and accessories. Hardware items, parts that are used with the product being manufactured, cleaning materials, special packaging materials and special labels should be considered for inclusion in this section of the checklist.
Job in Process
For a job in process, quality checklists describe things the operator should be monitoring as the job is being performed. This may also require verification of things that were done earlier. Typically, the following information is included in the job-in-process section of the quality checklist:
• Condition of material and components. Certain materials or components may need to be checked to ensure that they are fit for their intended use. Chips, dents, scratches, cracks, excessive burrs, sharp edges or foreign matter in holes may render a product unusable, yet they are easy to see, so they should be included on a checklist.
• Special finish requirements. Painted or chemically treated surfaces should be checked during the manufacturing process. Is the finish consistent across the part? Is it missing from critical areas of the part? Is there overspray in areas that should be free of paint? Is there evidence of surface finish in holes that are supposed to be “clean?”
• Critical dimensions. Some dimensions may be so critical that they need to be checked and verified repeatedly. Sizes and depths of holes, distances between holes, angles, clearances, squareness and tapers are types of measurements that may fall into this category. Of course, complex dimensions will require that appropriate tooling or equipment be available to perform those checks.
Once you have identified what should be included in your quality checklists, create them with the following in mind:
1. Employ visuals whenever possible. A photo is best, but even a drawing included in the body of a checklist can be easier to understand than a description.
2. Avoid abbreviations and acronyms. Not everyone knows what they mean, and using them can lead to unnecessary confusion. The risk of making bad parts outweighs saving a few keystrokes.
3. In some cases, it may be necessary to list not only what has to be done, but how it should be done. For example, simply stating that the drawing issue on a part must be checked is not sufficient. Instructions on how to verify the correct drawing revision may also be necessary.
4. Anything that may be unclear to you will be unclear to others. We know what we mean when we write something, yet sometimes when we read it later, it does not clearly convey what we meant. Take a few extra minutes to make sure information on a checklist is as clear as possible.
5. Consider creating a quality checklist template that contains everything common to all jobs, and then add anything specific to new jobs as they arise. This forces consistency from one checklist to another, ultimately making things easier for those who use them.