Continuous improvement is an ongoing effort to make incremental changes in a company’s processes that improve efficiency and quality. While the concept is fairly simple, many businesses find it challenging to sustain continuous improvement over the long term.

Continuous improvement is one facet of Lean Manufacturing, which is a set of tools used to maximize output and minimize waste. The meaning of ‘minimizing waste’ in manufacturing is a far-reaching term. Some examples include:

• Unused material reclamation and recycling
• Cutting down on energy and transportation costs
• Reducing wait times
• Minimizing product defects and returns

In the context of Lean Manufacturing, continuous improvement helps companies produce the highest quality product for the lowest absolute cost. Continuous improvement is carried out over days, weeks and years through a series of incremental changes to the production process.

In this article, we’ll be looking at what continuous improvement means in practice across various industries, with a special emphasis on what it means for manufacturers, and how Eagle Precision Cast Parts, an investment casting foundry, utilizes the principles of continuous improvement in our Lean Manufacturing journey.

Continuous Improvement in Practice

While continually striving to improve process efficiency and product quality is exactly the type of thinking that we hope to master in the manufacturing world, manufacturing is not the only industry that leverages continuous improvement.

In healthcare, for example, continuous improvement strategies can help hospitals identify bottlenecks in surgery scheduling that result in suboptimal operating room use. Consequently, facilities can reduce the wait time between two patients' surgeries and can ensure that patients receive treatment in as little time as possible.

Another industry where continuous improvement is very active is in the retail banking space. Technological and programmatic updates in the industry, as well as the rollout of fraud detection technologies, have significantly reduced the amount of customers falling victim to fraudulent activity. In this case, there is a very obvious interest between all parties involved to reduce ‘waste’ because here ‘waste’ equates to actual dollars.

Even major retail chains like Wal-Mart and Target build continuous improvement into their core business strategies. Both companies actively seek opportunities to leverage technology and data to optimize processes, manage inventory and increase customer retention.

In all cases, data plays a significant role in guiding the decisions made by leadership.

Continuous Improvement in Manufacturing

Manufacturing has a particularly strong relationship with continuous improvement. In fact, manufacturing is where the whole idea originated and where it continues in its fullest form.

In earlier time periods where the physical manufacture of goods was really the only kind of industry outside of agriculture, some of the first factories began the practice of constantly looking for ways to do things better.

Today, continuous improvement in manufacturing is almost synonymous with the advances made by Japanese heavy industry firms active after World War II. Kaizen, a Japanese word meaning ‘change for the better’ (or for our sake, continuous improvement) is a household term in Japanese culture. When Kaizen was adopted into the world of modern manufacturing, it marked the beginning of a new era.

Japanese automaker Toyota is the heavy-hitting originator of many of the Lean Manufacturing practices used today. The well-known Toyota Production System (TPS) was developed to provide systematic and thoughtful solutions to some of the efficiency problems identified on factory floors.

Continuous Improvement and Lean Manufacturing

Continuous improvement and Lean Manufacturing can be thought of as separate methodologies, but they have a lot in common. In fact, many Lean practitioners consider continuous improvement to be a basic tenet of Lean Manufacturing. While Lean comprises a larger set of tools and principles, its core aim is to bring about improvements in efficiency and quality.

Whether implemented as part of a broader Lean Manufacturing strategy or as a standalone process, continuous improvement is a constant and ongoing effort that usually progresses through incremental steps over time. It’s not generally seen as a complete system change or overhaul, but rather a series of modifications (it’s more ‘evolution’ than ‘revolution’).

"Continuous improvement is more evolution than revolution"

Continuous Improvement in Investment Casting: Eagle Precision’s Lean Manufacturing Journey

The art of observation stands at the center of an effective continuous improvement program. There can be hundreds, even thousands, of places in the production process that are candidates for changes that could be beneficial to the overall workflow. In the case of Eagle Precision, we make sure key employees are trained in the principles and practice of continuous improvement. As part of their day-to-day activities, they perform regular production audits.

A production audit is a comprehensive program of observation and system-tracking, where an employee conducts a holistic and detailed examination of the production processes and systems within a manufacturing facility. A typical production audit at a metalcasting foundry starts with a visual inspection on the factory floor. Here’s an example of how AJ Menefee, VP of Technical and Engineering at EPCP, conducts one of his production walkthroughs:

"We’re doing a walkthrough until we see a process or procedure and think, “Why are we doing it that way?” Then we start to investigate and see if there's a better way to do it. We start asking questions like, “Hey, have we looked at trying this to help reduce the gross weight so that we improve the yield on that product?” Or we notice a certain common defect on a specific part all the time: what can we do to fix that, so we don't have to worry about it again?"

In continuous improvement, man and machine work closely together because team members must be trained to interpret and utilize data. For example, manufacturers can collect data on production metrics like cycle times, defect rates, and equipment downtime, in order to better predict delivery timelines as well as total production costs.

However, data alone doesn’t get the job done. Training personnel to appropriately utilize data and develop a sharp eye for snags in the production process is essential for success. By focusing on a particular machine to analyze metrics like its defect and downtime rates, a trained team can use a statistical approach to predict when a machine’s next downtime will likely occur. That knowledge can help produce a solution, like preparing to reroute the production process through a replacement channel when needed.

On the basis of continuous improvement, EPCP has made several major investments in recent years that have significantly improved aspects of our production:

Wax Room

EPCP set out to boost the efficiency of creating the wax molds we use in investment casting, and two new practices have shown significant results:

Die Design

We were determined to find a way to cut down on the time per job that the die is being run on the press, which simultaneously reduces labor hours and tooling wear. The solution we found was to migrate from single-cavity tooling, which requires a good deal of manual input, to semi-automatic multi-cavity tooling. Thanks to our new semi-automatic multi-cavity dies, much of the wax injection and ejection process is automated.

Yield Improvement

On an audit, one of our employees spotted an opportunity: by increasing the number of wax patterns we attach to a single tree, we can improve overall throughput. With a few modifications, we can reduce the number of trees and carry more pieces per tree. The efficiency gains here result from more pieces per tree, and less wasted wax and metal.

Robotic Cells

EPCP has been employing two robotic cells that exemplify the advantages that continuous improvement can bring to a factory floor. When deployed in their optimal setting, robotics can bring enormous cost savings and quality benefits to a foundry.

Robotic Dipping Cells

EPCP employs a Fanuc articulated robot arm in the dipping process. This means that, instead of a manual operator holding the tree and dipping it in the mixing tank to cover it in slurry, the Fanuc arm performs the operation, rotating the tree over the tank to rid the tree of excess slurry. The robot arm then transfers the tree to the sander. Once the tree is adequately sanded, the Fanuc arm hangs the sanded pattern tree onto the conveyor for drying.

Eagle Precision also has a newly installed Dip Mate system from AW Bell. This modular robotic dipping cell allows an operator to essentially hand off a pattern tree to a robot arm, which then dips and sands the tree and passes it back to the operator for drying. This streamlined setup eliminates the need for a dedicated conveyor system, but provides the benefit of freeing up employees’ time and providing more consistent dipping for nearly any part.

For a deeper dive on our robotic dipping cells, click here.

Robotic Grinding Cells

Grinding is an essential after-cast process, and one that is a perfect candidate for automation. Our robotic grinding cell consists of a Fanuc pick-and-place arm, and a RGS230 Revolving Table Grinder manufactured by AW Bell.

The revolving table grinder allows us to set up multiple small to medium sized castings with high production runs, producing dramatically higher production rates than conventional grinding methods. The continuous mode is only limited by the load and unload time of the operator or the pick-and-place robot.

For a deeper dive on our grinding installation, click here.

What Continuous Improvement Means for Investment Casting Customers

The ultimate goal is to save time and money, all while creating a superior product with shorter cycle times, fewer defects and less significant variations.

The process of constantly refining and optimizing production leads to higher quality products, faster delivery times, and cost savings that get passed on to customers. Most importantly, continuous improvement increases reliability. Customers of factories that employ continuous improvement can expect their parts to be delivered on time, every time, and with minimal returns. While setup costs like tooling may be less, the lifetime cost of a project can be exponentially higher if processes aren’t optimized foundry-wide.

Additionally, all companies within the Eagle Group, including Eagle Precision, are ISO-certified. With that certification comes responsibility toward continuous improvement and Lean Manufacturing. Embedded in the ISO certification process is an analysis of how a company designs their "Process Approach to Continuous Improvement." What this means on a go-forward basis is that evaluations are constantly being made to determine whether the attempted improvements have actually resulted in yield improvements. As a result, customers can rest assured that ISO-certified companies aren't wasting time and money on false upgrades. By encouraging products that are more reliable and cost-effective, continuous improvement is a win-win for both manufacturers and customers.

This ongoing commitment to improvement ensures that customers benefit from higher quality products, faster delivery, and better overall value.

Learn more about Lean Manufacturing: Download our Lean Manufacturing Timeline below: