Medical device manufacturers often turn to contract sheet metal fabricators with automated capabilities.

Some type of enclosure, cart, or cabinet typically serves as a user workstation or protects sensitive electronics, controls, and hardware in medical diagnostic and test equipment. While not fancy, there is more to forming enclosures than meets the eye. Component parts require tight tolerances that fit and work in the design, and selecting the correct finish is important. Even the precise placement of electronics and hardware require careful consideration. The cabinet or cart must allow for easy use and movement, take into account ergonomic considerations, provide ease of maintenance and repair, and accommodate future upgrades.

Contract sheet metal fabricators with highly automated equipment often supply medical device manufacturers with enclosures. In addition to speeding production, contract manufacturers can increase part precision, often at a lower cost; and some fabricators provide full assembly, packaging, and direct-to-customer shipping of the final enclosure.

Cardiac platform

Soteria Medical employed the automated processes of a contract manufacturer to improve the production of its Cardiac Platform Cart, designed to detect atherosclerosis at an early stage.

“Over 1 million deaths in the U.S. annually are due to atherosclerosis,” says Dr. Jeffrey Raines, CEO of Soteria Medical. “We developed the first device that quickly, accurately, and non-invasively measures arterial buildup, so it can be addressed at earlier stages to change the trajectory of the disease.”

The Soterogram, a 15-minute test, uses pressure cuffs on the patient’s arm, calf, and thigh to measure arterial volume changes to determine compliance of the artery wall.

To fabricate Soteria’s medical cart, Precision Metal Industries (PMI) employed cutting, machining, forming, welding, and painting.

However, the company required help to create a cardiac platform on a custom cart for hospitals, clinics, and doctors’ offices. The platform would include additional modules for registration, lower extremity peripheral artery disease evluation, and other testing.

After a previous medical cart did not meet requirements, Soteria turned to Precision Metal Industries (PMI), a Pompano Beach, Florida-based sheet metal and precision machining contract manufacturer. Creating CAD drawings for the enclosure from Soteria’s input, PMI employed various automated manufacturing capabilities to fabricate a custom cart to house and protect the sensitive equipment – cutting, machining, forming, welding, and painting the sheet metal items. PMI is ISO 9001:2008 certified and uses a quality management system.

PMI equipment includes:

  • Prima Power Platino 2.0 4,000W fiber optic laser
  • Amada 80-ton, 8ft brake with triple axis backing gage
  • Haas VF-4SS vertical machining center

PMI employees painted 43 subcomponents, assembling them into one complete unit.

“Having a clear quality assurance program is vital to us and the FDA, and must be present in order to sell, lease, or place this type of medical device,” Raines says, acknowledging that automation does much to reduce human error and improve quality, so working with a contract manufacturer that can automate many of the processes in manufacturing medical enclosures can be an effective strategy.

“Custom automated laser cutting is among the most effective processes for cutting plate or sheet metal for fabrication,” says Gregory S. Wilson, Jr., PMI’s vice president and general manager. “The technology allows cutting precise, accurate geometric shapes, no matter how irregular or unusual. Once programmed, it requires zero setup time and allows unattended processing for efficient longer runs on a 24/7 basis that can expedite production and lower cost.”

Advanced CNC press brakes ensure precision bending and forming, with software minimizing setup and lead times, allowing for very close control of positioning, velocity, coordination, and feed rates.

PMI’s approach includes precise, fully automated robotic bending and forming done lights-out with minimal labor, setup, and lead times. This can involve tools such as CNC press brakes to create U-bends, V-bends, and custom forms from flat metal sheets, as well as folding. With off-line programming software, once setup is done, the equipment eliminates human variability and ensures a repeatable, reliable process.

Automated robotic welding within a specially configured cell offers consistency and repeatability, producing controlled-seam welds with little splatter. Automated welding minimizes human error, improves reliability, and maximizes yields, reducing cost.
Precision Metal Industries (PMI) uses CNC press brakes to create U-bends, V-bends, and custom forms from flat metal sheets, as well as folding.

PMI has also added finishing and assembly capabilities. Automated finishing services using spray booths and ovens can apply wet paint or powder-coat to parts to withstand harsh cleansers and disinfectants.

According to Raines, the contract manufacturer streamlines the entire fulfillment process.

“Based on a bill of materials and detailed specifications provided by us, PMI purchases the electronics and accompanying hardware, which includes a pump, exhaust valve, blood pressure monitor, air manifold, piston, linear actuator, and other items,” Raines explains.

The contract manufacturer then assembles the components into a working custom cart, and calibrates the system using Soteria’s software.


“It starts out as sheets of metal and when [PMI] is done it comes back as the Soteria Cardiac Platform,” Raines says. “Under our instructions, they also package and ship the carts to expedite delivery. With the automated manufacturing processes, the quality from PMI is better than if we built it in-house as the original equipment manufacturer (OEM). When it can be built and assembled better, faster, and cheaper that way, it makes sense to do it.”

Growing customer base

Other OEMs have noticed how automated processes improve quality and lower cost. For instance, Beckman Coulter also uses PMI’s services for its cellular analysis system that improves productivity in hematology laboratories. In this case, the contract manufacturer does all the sheet metal, machining, forming, painting, welding, and cabinet housing assembly before the OEM assembles the electronics and medical instruments into a working unit.

Precision Metal Industries Inc.

Soteria Medical