Corvus Surgical designs reusable handheld instruments for outpatient procedures. Their newest handle had to do something deceptively hard: stay perfectly smooth, corrosion-free, and dimensionally stable through hundreds of steam-autoclave cycles, because a reusable instrument that pits or roughens becomes an infection-control problem.
Reusable means it has to last
A single-use instrument only has to survive one procedure. A reusable one is cleaned, inspected, and steam-sterilized after every use, over and over for years. Each autoclave cycle is a corrosion and thermal test, and any micro-crevice or surface roughness becomes a place biofilm can hide.
Corvus needed a handle with an ergonomic grip, tight interfaces to the working tip, and a surface that stayed clinically smooth for the life of the instrument.
Material and finish do the heavy lifting
The material choice was 316L stainless — low-carbon for corrosion resistance and a standard for reusable surgical devices — machined to hold the tip interface and detent features to ±0.03mm so the assembled instrument articulates cleanly every time.
The finish is where a reusable instrument is won or lost. An electropolish removes the surface layer, rounds off micro-peaks, and leaves a passive, easy-to-clean surface that resists the pitting repeated sterilization can cause.
The part we built
We machined the handle from 316L bar, held the critical interfaces to ±0.03mm, and electropolished every piece. The result is a handle that feels right in the hand, mates precisely to the working tip, and presents a smooth passive surface to the autoclave.
Corvus validated the design with repeated sterilization testing before release, and we supply it with the documentation a medical program expects.
Still smooth at cycle 500
Through Corvus's accelerated sterilization testing — on the order of 500 cycles — the electropolished 316L handles showed no meaningful pitting or dimensional change, and the tip interface stayed within spec. That gave Corvus the reuse-life claim their customers were asking for.
For a reusable instrument, longevity is the feature. Getting the material and finish right up front is what makes the whole business model work.
“Reusable is a promise about the hundredth procedure, not the first. The electropolished 316L handles came back from cycle testing looking new.”
Dr. Alicia Berg, VP Product, Corvus Surgical