In manufacturing – just like in nature – no two things are ever the same. But during the production of precision components our ability to control that process keeps any variation between the parts within limits that meet our customer’s expectations. Understanding the causes of any possible variation and planning for those causes is key.
At Swiss-Tech we follow a robust process when planning exactly how our team will manufacture a part to ensure that the variability is not only understood by everyone involved in the process but also controlled – which ensures we produce products that meet all of our customer’s expectations.
Evaluate design, critical features
It starts by understanding the design of the customer’s part, which includes identifying exactly which features are critical.
“Our team understands that our customers ask us to produce mission critical parts. These parts cannot have mistakes and must function exactly as intended. So, when our engineering team considers what is critical, we’re not only interested in what is critical to our customers, but also what is critical to our production process,” said Jason Price, Director of Engineering and Support Technology.
Determining all of the critical pieces to a customer’s project is critical in planning new product introductions into our facility because it focuses our teams on determining any possible variations caused by the manufacturing process. Through careful planning, analysis and execution our team determines appropriate steps that must be taken during the manufacturing process to ensure we can mitigate any variations that go outside acceptable limits for the part.
“This advanced quality planning is a necessary step towards proactively eliminating wastes such as unnecessary time, costs and possible scrap,” Price said.
Create manufacturing, inspection plan
Next in the advanced quality planning process is our involvement of a group of team members from different departments who perform different functions. The group meets, reviews and discusses the proposed manufacturing plan. That plan includes the CNC machine tool path, which tooling to use and the sequence the machine operations will occur.
Every facet of the overall process is discussed, including which machine and gauges will be used, how the product will be measured, process drawings and the development of work instructions that will be needed to take the part from a design to a physical product.
“At Swiss-Tech, creating these plans occurs over time through a phase and gate approach,” Price said. “As the development activities are completed in phases, verification steps known as gates are put in place along the way.”
Qualifying run specifications
The team is focused on achieving stability in manufacturing during each phase of introducing a new part. The first, or qualifying, run of the part is critical because the team discusses and evaluates the manufacturing process’ capability – which is the ability of a process to produce output within specification limits.
“We want to deliver a process that will produce a conforming product each and every time. Our team thinks about this in detail from the start so that we plan in the quality we want to achieve,” said Jeff Duesterbeck, Engineering Machinist Programmer.
Another part of reducing variation in the process involves what gaging is best suited to verify the measurements of the machined parts. Reducing variation when measuring the part improves our team’s confidence to assess the overall process and makes it easier to assess any variation present in just the machining process itself.
“Things get really interesting during the machining process at the initial production run because the team qualifies the decisions chosen during the planning process,” Duesterbeck said.
During the qualifying run, the team uses statistical measurements and evaluations to determine if any tweaks or changes need to be made to improve the process. If any changes are made, the plan is updated, and the qualifying run is repeated to ensure the capability of the process has improved.
“The measurements and evaluations give us the evidence to prove we have control over our process and confidence the parts we’ve produced are correct,” Duesterbeck said.
Standardizing process, training operators
Once the variations in the manufacturing process are determined to be acceptable and stable, the team documents how the machine is set up, how the part should be inspected, and how often the part will be inspected.
“All of this will be determined just before our operators are trained and the process is handed-off to them to start running the part,” Price said. “Including the operator ensures a feedback loop is present, and that what the team has developed is clear and understood.”
All subsequent production runs of the part will then follow all of the documented requirements set in place by the introduction team, and all of those details are monitored over time, along with Statistical Process Control software that provides operators real-time feedback that their process remains in the specified variations.
“If any improvements are planned at a later point in time, such as changing from one type of drill bit to another, having SPC in place makes evaluating the effects of the change must easier,” Price said.
Parts that come as close to identical as possible
While it is true that no two things are ever made exactly alike, the Swiss-Tech team recognizes that variation can be controlled within a process and focuses on reducing it through careful planning. Our operations team can then repeatedly execute the plan, producing parts through a verified process that ensures only conforming product will be received by our customers.