Trelleborg adds capacity for silicone, TPE medical devices

While the medical device industry may be expanding, the medical devices themselves are getting smaller, with tighter thresholds required in both material and molding.

In response, Trelleborg AB has expanded its silicone and thermoplastic molding capacity at Trelleborg Healthcare and Medical in Delano, Minn., building a 6,000-square-foot ISO Class 7 clean room and adding equipment for greater molding and manufacturing capabilities — including the micro-molding of silicone medical devices.

"We have increased our capacity for silicone molding while also refining the setup to leverage existing capabilities, such as the in-house tool room, to reduce lead times," said Dave Pool, operations director of the Americas, Trelleborg Healthcare and Medical. "The added space also enables us to expand our contract manufacturing capabilities to accommodate the increasing demand for product development."

Trelleborg has about 300 employees at the Delano campus between its two facilities there, a footprint that comprises about 90,000 square feet of space, including the 6,000-square-foot expansion.

The project brings to Trelleborg's Minnesota hub an in-house tool room, new presses, micro-molding machines and other equipment designed specifically for silicone molding, though the site also works in thermoplastic injection molding. The company has added a material mixing station, clean room silicone storage space, alcohol wash, tumbling machines and a packaging cell, Pool said. Trelleborg also can machine high-precision metal components at the site.

The capital investment in the new space was not disclosed by Trelleborg.

Unique to the Minnesota campus is the in-house tool room, allowing Trelleborg to build injection molds and automated solutions on site for its customers, Pool said. The tool room enables rapid response times, especially when prototyping new parts, and allows the company to precisely control the quality of parts throughout the molding development and production lifecycle.

"Vertical integration enables us to maintain greater control over quality and lead times for strategic customers," Pool said. "When we partner with customers for a new device design, it's often an iterative process to develop the optimal part. While we can remove guesswork through finite element analysis and mold flow analysis, being able to adjust the tool to optimize the part is a critical step in the process."

In addition, as the tool ages, maintenance may be required to keep it running in peak performance, and collaboration between the production and tool room employees keeps the tool in top condition for as long as possible.

"Trelleborg engineers partner with customers to optimize device designs for manufacturing, prototype parts and scale-up to production volumes," Pool said. "This can include designing a tool that matches the customer's quality expectations, creating an automated assembly process for multi-component parts or working with customers to choose the optimal material for their design. Nearly everything we do is a custom part catered to our customer's specific device requirements. Our customers partner with Trelleborg to help bring their devices to life."

All of this is especially important in the medical device realm, particularly in the small-margin, micro-molded space, a burgeoning market due to the pandemic and re-emergence of elective surgeries.

"Initially, we saw an increase in demand for respiratory system components and a decrease in demand for products used in elective procedures," Pool said. "But demand has begun to return to a normal mix as elective surgeries have returned to normal levels."

In micro-molding, Pool noted that both equipment and approach are different due to smaller shot sizes and specialized metrology. As parts get smaller, he said, attention to tolerances becomes increasingly critical.

"Part design, tool design and equipment design all need to be optimized to assure that the production process is accurate and repeatable," he said.

The virtues of molded medical device parts include the ability to form complex geometries out of silicones or thermoplastics, as well as the repeatability of the part in both low and high volumes, based on the cavitation of the tool used, Pool said. Molded components are found throughout the medical device market, including end applications in cardiology, orthopedics, neurology, general surgery and others.

And while silicone and TPEs are the most common raw materials used to produce both traditionally molded and micro-molded medical parts, silicone is unique due to its biocompatibility for long-term implantable devices, Pool said. TPE parts are more often found outside of the body in surgical tools and implant aids, or other tools required for the surgeon.

"In Delano, we micro-mold components with medical grade silicone and thermoplastics, but the clear favorite is silicone," Pool said.

The operations director said silicone is sought for its non-reactive qualities with other elements; its ability to be platinum-cured for a high degree of purity; its easily altered durometers; its good tensile strength; and its versatility for use in a wide range of temperatures.

As demand increases for medical devices both large and small, inside the body and out, Pool said Trelleborg sees increased market opportunities.

"Medical device development is not slowing down," he said. "Devices continue to push the barriers of size, becoming smaller and smaller to drive a less invasive experience for the patient. Digitization of care is also a trend accelerating in the market, and more is being done to monitor and address patient conditions real-time for a better therapeutic result."