Custom Medical Equipment Gaskets for an Ambulatory Infusion Pump

A medical device OEM needed 13 custom gasket parts and protective packaging foam for an ambulatory infusion pump, moving production back to the United States from an overseas supplier. H-O Products translated and adapted the original drawings, re-specified every material to a U.S.-available equivalent, developed a converting process capable of holding tolerances as tight as ±0.001 in., and put one critical gasket under 100% automated inspection.

BACKGROUND

Gaskets do quiet but consequential work inside medical devices. In ambulatory infusion pumps, insulin pumps, metering devices, and imaging equipment they seal against fluid and gas leakage, support consistent pumping performance, and keep moisture and dust away from sensitive internal components. In a life-critical device, a small variation in gasket performance can change how the device behaves, which is why precision and repeatability matter more than catalog availability.

The OEM came to H-O with 13 custom gasket parts to produce, plus custom medical packaging foam to protect the finished pump against impact, vibration, and contaminants in transit. The pump had previously been built overseas, and the program was being reshored. Neither the manufacturing process nor the U.S. material set existed yet.

CHALLENGES

1. Tolerances tighter than standard converting. The OEM’s dimensional requirements ran as tight as ±0.001 in., and the process had to hold them from prototype through large-volume production, not just on a first article.
2. Drawings in another language, built to another standard. The technical drawings arrived in Chinese and had to be translated and then adapted to U.S. manufacturing practice.
3. Materials that did not exist domestically. Once the drawings were readable, the specified foams, gasket stock, and adhesives had to be matched to U.S.-sourced equivalents, then tested and approved by the OEM.
4. Stock thickness that did not match the design. One foam gasket bonded to low surface energy thermoplastic polyolefin (TPO) called for a thickness the available U.S. stock did not hit. The gap sat within normal material tolerance, but not within what this device needed.

SOLUTIONS

H-O used its engineering group and outside translation resources to interpret the drawings accurately, then worked material by material to find domestic equivalents. The original design specified acrylic foam tapes; H-O researched the adhesive options and selected low surface energy (LSE) adhesives that would bond reliably to the pump’s surface materials. Every substitution was re-specified, tested, and submitted to the OEM for approval before it went into the build.

Production drew on several converting methods rather than one: steel rule cutting, precision rotary tooling, and laser cutting, chosen part by part against the accuracy each geometry demanded. For the TPO foam gasket with the thickness mismatch, H-O buffered the raw material on a machine adapted specifically for this program, bringing the stock to the exact gauge the design required. That step is what let the finished part meet a specification the available material could not meet on its own.

The collaboration ran several months, with H-O engineering and the OEM’s engineers and designers working through material selection, prototype iterations, and tolerance decisions together. The OEM team was closely involved in choices about material gauge and the converting method itself, and H-O modified machinery at several points to suit the particular behavior of the foam and adhesive combinations. Those adjustments were what made process validation achievable at the required precision.

QUALITY & INSPECTION

For components going into a life-critical device, sampling was not the right control on every part. On one gasket, H-O implemented 100% inspection: each piece was automatically inspected as it came off the line and checked against its tolerance before shipment. The customer still ran its own inspections on receipt, after installation, and at system assembly, so H-O’s in-line check was the first of several gates rather than the only one. All of it was performed under H-O’s ISO 9001:2015 certified quality management system.

RESULTS

The program delivered 13 custom gasket parts plus protective packaging foam, produced domestically to a validated process. H-O re-specified the material set to U.S.-available equivalents with OEM approval, held dimensional requirements as tight as ±0.001 in. in ongoing production, applied 100% automated inspection where the device demanded it, met the customer’s budgetary targets, and completed the reshoring of the parts for the project.

The OEM did not arrive with a domestic process waiting to be run. It arrived with drawings in another language, a material list that did not exist in the U.S. market, and tolerances tighter than the stock could deliver. Working through translation, substitution, machine adaptation, and inspection turned that into a repeatable production program.

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