By Patty Rasmussen, for East West
A 2013 study by the Lenox Institute of Technology of more than 100 industrial metal-cutting operations found that, “regardless of the percentage of machine uptime reported, respondents admitted that finished products don’t pass first inspection 20% of the time and require rework.”
First Published on East West Manufacturing Blog, read more here.
It’s not unreasonable to assume that similar rework percentages exist in other manufacturing operations. So, rework happens, not infrequently, and dealing with it is a hassle. Correcting defective parts means lost time, increased waste and unplanned costs. Figuring out ways to reduce manufacturing rework leads to cost savings, more productive use of time and overall higher quality products.
What’s Rework Anyway? According to Business Dictionary, rework is defined as:
Correcting of defective, failed, or non-conforming items, during or after inspection. Rework includes all follow-on efforts such as disassembly, repair, replacement, reassembly, etc.
There are several reasons why a product could be found to defective or requiring rework:
- Machine malfunction or human error
- Design change not communicated (at all or in a timely manner)
- Design change not implemented properly
- Product damaged in transit
- Product damaged in use
When a rework is required, the manufacturer/supplier receives a document outlining instructions to complete the task. This will include sorting, reworking, washing and repackaging. The document will list the tools necessary for the rework, and the process – with photos showing what to look for on the affected parts.
For example, rework could be relatively simple, maybe during inspection a plastic part is found to have burrs (extraneous material). The manufacturer would remove the material (deburring) either manually or mechanically. Or perhaps paint is scraped off pieces during shipping. Those pieces would be repainted, and changes would be made in the shipping process to protect the pieces in the future.
Five Ways to Reduce Rework Costs
We’ve identified five ways you can cut back on reworking costs and associated expenses that will protect your bottom line, and improve efficiency and quality across the supply chain.
1 | Update and maintain an organized filing system
If your company is still using paper files, they must be backed up digitally. But take it a step further. It’s time to invest in digital software and filing systems to manage your CAD drawings, bills of materials (BOMs) and standard operating procedures (SOPs). Using digitized files makes it much easier to track revisions, ensuring your employees are referencing the most up-to-date, accurate information at all times. Investing in project management programs also reduces the risk of ordering incorrect components or building to an old revision level.
2 | Communicate quickly & completely
Communicate design changes to your contract manufacturer immediately. Changes can cause significant disruption to production if it’s not handled properly. If you are making a major revision, it could affect the flow of production, required training, scheduling and total cost, among other factors. Remember: If your contract manufacturer works with additional suppliers, they need time to communicate the changes to those suppliers as well.
It’s best to avoid making major design changes in the middle of a production run. Instead, wait until the next order for full implementation to ensure the change is adequately planned and executed. This will also make the product revision levels easier to track for you, the supplier and your customers.
3 | Be proactive
Preempt quality control issues by taking a proactive rather than a reactive position. Make regular factory inspections to identify problems and to look for ways to improve processes. You want to find the root cause of the issue and resolve it as early and as simply as possible. Could the problem be solved by:
- Acquiring new equipment and fixtures
- Improved employee training
- Software upgrades or additions
- Greater attention during design phase
- More emphasis on pre-production processes
- Additional packaging/handling procedures
4 | Implement and emphasize quality control procedures
‘Continuous improvement’ is more than a buzzword. Using a well-developed and tightly monitored quality control procedure is essential to minimizing costs associated with rework. Adopting a Total Quality Management (TQM) philosophy and implementing the PDCA Cycle or another closed loop, continuous improvement system is a great start. Six Sigma quality and Lean manufacturing practices will help you eliminate waste and improve quality.
Action tip: If you do not already do so, launch a Corrective and Preventive Action (CAPA) program to diagnose an issue using the Eight Disciplines process, assign a team to address it, and resolve it within a specified time frame.
5 | Create a Scrap Materials Plan
It is always preferable to repair or alter a product, but sometimes scrapping is unavoidable. In the event you need to scrap, try to reduce the amount of waste as much as possible. Depending on the material or location:
- Can you avoid dumping fees?
- Can the product or individual components be refurbished or repurposed?
- Can parts be recycled?
Rework may be a fact of manufacturing life, but it shouldn’t consume your time and energy. Following through with our five tips can simplify your life by having good quality processes in place, that should result in even better products for your customers