A global medical device manufacturer was using convection reflow systems paired with a custom FEP heat shrink film to weld catheter components. While effective, the process was resource-heavy and time consuming, with each weld taking six and a half minutes and requiring a single use consumable costing US$ 4 per cycle. With a production need of 200,000 cycles annually, these material costs alone add up to US$ 800,000 each year, not to mention the labor and energy costs of long cycle times in a cleanroom environment.
Seeking to modernize their approach, the manufacturer turned to PackworldUSA to explore impulse heat sealing as an alternative. The results were immediate and significant. Cycle times dropped from 6.5 minutes to just 6 seconds, enabling a 65x faster process. Eliminating the consumable FEP film not only cut material costs but also improved overall sustainability by reducing plastic waste and eliminating a fluoropolymer from the same family as PFAS chemicals like Teflon. This efficiency gain translated into more than 21,000 hours of cleanroom labor saved annually, freeing up personnel and production capacity.
Beyond the financial savings and improved throughput, the switch to impulse heat sealing mitigated the company’s dependence on external suppliers. By removing the FEP consumable from the equation, the manufacturer reduced its exposure to supply chain risks, an increasingly important consideration in today’s volatile manufacturing.
Evolution of impulse heat sealing
Impulse heat sealing has come a long way in recent decades. Early machines operated on a fixed-power model, delivering the same amount of current to the heat seal band in every cycle. Over time, this approach caused the sealing jaws to retain excess heat, leading to overmelted plastic, seal failure, and invalid results. These machines lacked process feedback and weren’t capable of delivering consistent or certifiable results, making them unsuitable for industries requiring high repeatability like life sciences.
The next generation introduced thermocouples to the heat seal band to create a feedback loop, but these sensors were too slow for fast sealing cycles and often imprecise due to poor installation or movement from operation. This led to under- or over-heated bands and unreliable sealing.
PackworldUSA’s approach represents the latest and most advanced stage in this evolution. By eliminating thermocouples to monitor temperature in cycles, their machines instead use a heat seal controller to both measure electrical resistance and meter power. This real-time calculation offers a direct correlation to temperature and enables an extremely fast and accurate feedback loop.
The Toss Pireg temperature controller enhances this precision further, taking 50 to 60 resistance-based temperature readings per second to ensure optimal sealing conditions are met consistently across every cycle. Packworld machines are engineered to heat seal bands quickly with a benchmark goal heating to 572F (300C) in 400 milliseconds, in contrast to other impulse designs in the market which heat 100F per second or slower. Quick heating times enable faster cycle times and ensure consistent seal temperature throughout the cycle as plastics pull heat from the seal bands. This advancement in heat management has made impulse sealing not only faster and more energy efficient, but also fully validatable, therefore opening the door to wider adoption in sensitive and highly regulated production environments.
Technology that solves for medical manufacturing
PackworldUSA’s impulse heat sealing technology offered benefits beyond speed and cost. It addressed a deeper set of needs specific to medical device manufacturing: process control, repeatability, and the ability to validate. In life sciences, manufacturers are often hesitant to change validated processes due to the regulatory burden of re-qualification. However, in this case, the performance improvements were so clear, and the solution so precisely controlled, that the investment in change was justified.
Unlike constantly heated systems that require 15 to 20 minutes of preheating, impulse heat sealing equipment is ready to run in under a minute. It also supports a cooling cycle after the sealing temperature and dwell parameters have been achieved, which is critical for producing hermetic seals with materials lacking good hot tack properties. Some components require that cooling step for functional integrity, but even when it’s not strictly necessary, it often produces a superior cosmetic finish. With impulse sealing, only a thin heat band, about the thickness of a razor blade, is energized, allowing the sealing area to heat and cool rapidly. A focused heating area at sealing temperature only when needed reduces energy consumption and keeps tooling at lower temperatures for quicker handling if the need should arise. The precision of this method supports better overall product quality while making the process highly adaptable for medical device manufacturing.
Precision, repeatability, and validatability
A cornerstone of impulse heat sealing’s suitability for medical device applications is its unmatched temperature control. For a process to be validatable, it must be consistent and measurable, which is only possible when heat can be precisely applied and accurately tracked. PackworldUSA’s systems achieve this through their PIREG controller, which calculates and monitors temperature in real time using electrical resistance.
Instead of relying on thermocouples, which are slow to respond and often deliver inaccurate readings due to misalignment, PackworldUSA’s technology reads the electrical resistance of the heat seal band directly. The system takes 50 to 60 measurements per second, translating those resistance values into real-time temperature data via Ohm’s Law. This provides the kind of fast, accurate feedback loop required to maintain tight process control over short cycle times. The result is a level of repeatability and consistency that meets even the most stringent requirements for medical manufacturing.
The PIREG control system delivers real-time temperature monitoring, measuring resistance 50 to 60 times per second, to ensure consistent, validatable seals in every cycle.
As the Senior Principal Manufacturing Engineer on the project explained, “We were able to eliminate the need for a custom FEP heat shrink consumable in our process. This allowed us to remove the dependency on an external supplier that can have supply chain risks. In addition, reducing the cycle time from over 6 minutes to 6 seconds gives our manufacturing facility peace of mind knowing this equipment has no impact on the overall capacity of the manufacturing line.”
Reducing environmental and supply chain risk
The switch to impulse heat sealing also delivered sustainability benefits that aligned with the manufacturer’s long-term goals. By eliminating the use of FEP (a fluoropolymer material under the PFAS umbrella) the process significantly reduced plastic waste and minimized the environmental impact of production. The system’s low-energy profile, driven by short heating times and rapid cooling, further reduced the overall energy footprint.
In parallel, the manufacturer improved its resilience by removing a consumable-dependent step from its operation. With global supply chains under stress, this shift away from third-party material sourcing allows for even greater stability, predictability, and autonomy in production planning.
A new standard for medical sealing
For the catheter application, PackworldUSA supplied custom tooling to hold the components in place, paired with its modular sealing press. After testing the setup on PackworldUSA’s in-house machines, the customer quickly moved forward with purchasing three full systems, which are deployed across their facilities in California, Utah, and Ireland. Encouraged by the results, the company is now considering implementing the technology in other parts of its manufacturing process.
Impulse heat sealing enabled the manufacturer to dramatically accelerate production while cutting costs and improving process reliability. By reducing the sealing cycle from six and a half minutes to just six seconds, the company achieved a process that is 65 times faster. Eliminating the need for expensive FEP consumables translated into annual material savings of over US$ 800,000. The shift also freed up more than 21,000 hours of cleanroom time, allowing personnel to focus on other areas of production. Beyond time and cost efficiencies, the new method lowered the environmental impact of the operation and reduced dependency on external suppliers, mitigating supply chain risk. For medical device manufacturers facing similar challenges, impulse sealing offers a highly controlled, efficient, and sustainable alternative to traditional welding methods.
