Accelerating COVID-19 test kit production with turnkey metrology solution

On day four of isolation, having just had to pin my three-year-old down to swab his nose, a case study on COVID-19 test kits wasn’t exactly top of my wish list. Nevertheless Irish provider of turnkey metrology solutions, Verus Metrology Partners, has utilised a Renishaw Equator 300 gauging system with multi-station fixturing to accelerate COVID-19 test kit production.

The Challenge

SiO2 Materials Science (SiO2) approached Verus Metrology Partners for assistance in increasing the throughput of a metrology process vital to the bulk manufacturing of COVID-19 test kit components.

Verus Metrology Partners was tasked by SiO2 with performing high-speed batch inspection of two test kit components: a vial and a cap. Live inspection data recording was required in addition to component inspection.

Verus Metrology Partners’ Chief Operating Officer, Michael Nugent, said, “In this instance, time really was of the essence - in every sense. Not only did our metrology solution have to be developed in a short time frame, but it needed to repeatably and accurately measure critical component dimensions at the highest possible speed.”

He continued, “Social distancing measures and severe restrictions on both national and international travel of course presented a further challenge. A pragmatic solution was needed, one that made the best use of existing on-site inspection equipment and adapted it to work hyper-efficiently within a turnkey metrology system.”

The Solution

Renishaw's Equator 300 gauging system had recently been purchased by SiO2, but it had not yet been integrated into its metrology operations. The Equator gauge was a perfect match for Verus Metrology Partners' metrology system, “We were already aware of the capabilities of the Equator gauge, having put the gauging system through its paces in our R&D facility. In particular, we knew that it was capable of rapid inspection of parts.”

The Equator 300 system, which includes a programmable comparator gauge, controller, inspection probe, and application software, is designed for accurate inspection of medium to high volume parts.

Michael continued, “The working volume of the Equator 300 gave us the start point. Our solution would need to fit within the Equator 300 gauge’s working volume of 300 mm diameter and 150 mm height. When you know that a gauging system like Equator can perform very fast inspection routines, then the challenge quickly becomes: how can we get the most out of it? Inspecting single components one-by-one, even using some kind of shuttle system to load and unload, was just too slow and cumbersome. Given the relatively small size of each of the three components, we determined early on that multistation fixturing was perfectly viable and would give us the means to achieve the increased speed objective.”

Verus Metrology Partners designed and built a custom 8-station fixture for each component out of hard anodized aluminium and medical grade polycarbonate. This places tubes and caps in fixed positions within the working envelope, ready for probing, on a regular basis.

Michael commented, “The fixturing here plays a critical role. Not only does it need to present the Equator gauge with all the access it needs to inspect the two or five critical dimensions on each component, but it also needs to avoid any deformation of the component. It needs to support robust, repeatable metrology and can’t jeopardise the geometry or integrity of the component being measured – be it vial or cap.”

Verus used Renishaw's MODUS measuring software on the Equator Controller to create component gauging routines for the two distinct test kit component fixtures.

The QC-CALC statistical process control software receives all of the system's metrology data in real time. It can be printed and saved locally, with a graphically displayed Pass-Fail indicator for the machine operator.

The Results

Verus Metrolgy Partners has drastically reduced the batch release timings of SiO2 Materials Science's COVID-19 test kit components by combining an Equator 300 gauging system with customised multi-station fixturing. The Equator gauge runs the inspection routine at the touch of a button once it has been programmed. An operator simply places the vials or caps on the appropriate component fixtures, starts the Equator gauge's inspection programme, and leaves it to inspect eight components at a time.

Michael comments, “More and more attention is turning towards ensuring that all production personnel have roles and responsibilities that add real value to the business. Combining high-speed, automated gauging systems like Equator gauge with multi-station component inspection routines allows an operator to maximise the time they have available to produce parts and minimise the time taken to inspect them, leading to a more efficient and productive use of their time, which maximises ROI.”

“It is often the case that clients approach us looking for fixturing and metrology solutions that will serve them for a 20-year product lifecycle. And we say that our systems will frequently surpass the lifetime of the parts they’re designed to hold. In this particular instance of course, we sincerely hope a far shorter time frame will be required.”