In an increasingly volatile and complex market environment, adaptability becomes essential to success and business growth for today’s medical extruder. Basic to every processor’s manufacturing strategy is the identification, implementation, and advancement of the technological means required to ensure a firm’s products remain relevant in the ever-changing space. The medical marketplace advances rapidly, and the drive for higher performing, unique materials — coupled with increasingly stricter requirements for cleanliness, cost, and quality — remains a daunting challenge for many processors.

Figure 1. Piper Plastics uses computational fluid dynamics (CFD) analytical software and advanced engineering to design extrusion tooling with optimum thermal effectiveness to better control product quality and consistency. On the top is a CFD velocity study; on the bottom is a CFD thermal profile.

In practical terms, if a company or engineering team is familiar with a certain process or has a mature manufacturing technology, they have a confirmation bias to believe that the answer to the problem always is derived from their past experiences and existing processing methods. Developing cutting-edge products and processes to keep up with current trends, or better yet to help drive industry trends, requires breaking down the barriers of conventional thinking and fostering an environment where it is okay to fail. Promoting a culture that thinks “if you never fail, you are not trying anything truly noble” is critical to allowing your employees to challenge tradition and expand your business capabilities. Fear of failure can be as debilitating to a company as a bad business model, because without innovation, your company can become irrelevant and mature technologies become obsolete. On the other hand, trying something without the fear of failure could lead to breakthrough innovation for both you and your customer.

Here are some essential trends worth considering as you embark on re-engineering the processes that drive your business in this dynamic marketplace:

It’s science, not art. Science- and engineering-based process engineering is a cornerstone of a solid manufacturing process, and all medical processes must be validated, locked down, and repeatable without technician manipulation. The industry continues to want processes that are developed and maintained with a scientific foundation, and not “black art” or historical knowledge. Everyone in the supply chain is acutely aware that process audits are not only commonplace, but expanding to greater depths of sub-tier vendors, so customers want assurance that their supplier’s process is rooted in science and will pass the scrutiny of third-party auditors.

Analytical platforms, not trial and error. State-of-the-art polymer moldflow, computational fluid dynamics, and finite element analysis software platforms are needed to design the process tooling required by today’s designers. These analytical tools ensure the best polymer flow is achieved, eliminating low-velocity zones, and minimizing residual time and polymer degradation. These systems should also be used for the associated processes, such as sizing and cooling, to ensure optimum mechanical properties and product consistency are achieved. Looking at all conventional technology and challenging employees to develop innovative ways to dramatically advance common practices, coupled with the ability to iterate the conceptual design in the computer systems all before cutting steel, can result in dramatic process transformation (Figure 1).

Figure 2. Piper develops custom data-acquisition systems that monitor every aspect of the process using over 30 sensors per extrusion line. The top screenshot shows extrusion line data acquisition; the middle screenshot shows oven profile data acquisition; and the bottom screenshot shows a statistical page for data acquisition. The systems will e-mail engineering personnel if negative trends are detected and are being programmed to calculate and display running CPK (process capability index) data.

Know your process — don’t assume. Real-time measurement of the polymer in its molten state used to be limited to pressure and temperature, but now is moving towards the addition of real-time viscosity measurements. Molecular weight of the polymer plays a large role in the mechanical performance of the end product, and this characteristic can be altered during extrusion if not correctly processed, negatively impacting final product performance. Monitoring melt viscosity is an important input to maintain process control, and also alerts the process engineer of variation in the batch of polymer being utilized that otherwise would go undetected.

Process control — measure it so you know you have it. Data-acquisition systems to monitor process conditions are mandatory, but we also build in process trend alarms, e-mail notifications, real-time CPK, and statistical measurements so the technicians and the business are aware of current process conditions and trends. A typical production run now will be monitored by more than 30 sensors, all being fed into a centralized data-acquisition program that notifies process engineering via e-mail if they begin to trend in the wrong direction. This gives engineers and technicians the ability to identify and rectify a problem before the process reaches a lower or upper threshold limit (Figure 2).

Custom-built data-acquisition systems can monitor an entire extrusion system to record compliance, and are complimented with a serialization system that correlates the product coming off the line with exact process conditions. This is critical for post-production investigations if product variation is observed, and allows for accurate and thorough root cause analysis so effective corrective actions can be put in place and future occurrence eliminated.

How clean is clean enough? The medical industry will continue to pursue tighter cleanliness standards, so continuous improvement systems must be in place to challenge the status quo. In the semiconductor industry, customers have surpassed parts-per-billion and are now talking about parts-per-trillion in terms of contamination, and this thought process will ultimately bleed into the medical industry. This level of cleanliness surpasses the ability to see visually, and utmost care must be taken to ensure all aspects of the process are rigorously cleaned between production runs and surface treatments on tooling maintained.

All aspects of the process need to be considered as a potential origin for unwanted contamination, so everything from cleaning the incoming raw material, to installing high-temperature filtration on auxiliary equipment needs to be investigated to drive towards best-in-class products.

Material science. Whether it is to increase the performance of design or gain competitive security in the marketplace, customers are continually looking for alternative polymer formulations to meet their demanding applications. Often, the right polymer for the application is not the first choice from a processing standpoint. But if you want to provide a differentiated product, you must overcome the traditional barriers of hard-to-process polymers.

Confident transparency. Customers want to work together with their suppliers to solve difficult problems with technical solutions in a collaborative relationship. It is important to work with your customer’s design teams and offer valuable insight in altering a design for performance, cost, or production improvements. Collaboration instills confidence and builds a stronger relationship between you and your customers, which translates to additional business and a broader look at the commercial opportunities for our business. The philosophy is this: correctly solving a customer’s problem today is an invitation to participate in future product development tomorrow.

Be your customer’s expert. Processors must have key relationships with resin suppliers so they can get full support on existing and future polymers that will be introduced to the market. Diversification can aid in product advancements for one industry, and can be incorporated into products and manufacturing methods for other industries to give customers a unique product and help secure a position in their marketplace.

Figure 3. Piper Plastics goes beyond just process control and mechanically tests every lot and batch of product produced in their on-site analytical lab to ensure the product meets predetermined customer specifications.

Trust but verify. We can all become complacent by relying on robust product validations, process controls, and data-acquisition systems to shelter us from manufacturing a product that is out of specification and ultimately scrapped. However, those of us that have been around manufacturing for any period of time recognize that Murphy’s Law can jump into a process at any time. Inconsistent or incorrect lots of raw materials, rouge process sensors, and even ambient conditions can all have the potential to create process issues, and can be easily overlooked and difficult to explain to your customer.

For example, customers who want a medical manufacturing company with robust quality systems independently certified, like ISO 13485, view external audits not as a burden, but rather as a continuous improvement activity and an opportunity for them to assess the supplier’s operations and depth of the talent pool (Figure 3).

More than extrusion. We must always be concerned with bringing additional value to our customer from downstream machining, welding, and component integration all the way up to the final assembly. Customers are looking for vendors who are vertically integrated with multiple manufacturing disciplines under one roof as a way to further enhance finished assemblies and eliminate costs through vendor reduction.

Figure 4. Piper Plastic’s processing technology allows the production of non-standard shapes that yield exceptional mechanical properties to reduce material usage and drive large cost reductions. The near-net shape on the left is an example of a custom profile that replaces the original standard medical stock shape rod that is traditionally available in the marketplace.

Vertical integration usually equates to cost reductions, but more importantly, one source taking ownership of the assembly functionality can improve quality and speed the time to market. All too often in the conventional supply chain, sub-suppliers point fingers when problems occur with the final assembly. However, a vertically integrated supplier streamlines the process and minimizes issuesassociated with multiple supply partners.

When less is more. Sustainablity and waste reduction is important in all industries, but nowhere more critical than in medical implant extrusion, where the raw polymers can cost $1,000 per pound or more. Customers are no longer accepting that the traditionally supplied, standard shapes are the only option, but are investigating alternative geometries that drastically reduce material usage and better replicate the finished machined part (Figure 4).

This article was written by Dave Wilkinson, Materials Engineering Manager at Piper Plastics, Chandler, AZ. For more information visit http://info.hotims.com/61065-164 


Medical Design Briefs Magazine

This article first appeared in the September, 2016 issue of Medical Design Briefs Magazine.

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