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A wide range of inspections and verifications are needed for these parts. by Patrick beauchemin
Inspecting medical parts such as orthopedic implants and medical instruments pose a number of arduous challenges to manufacturers. Due to their vast array of geometries and materials, medical parts are difficult to manufacture and can be even more difficult to inspect. Regulatory require ments must be met as well as timely deliverables, adding to the need for a fast and accurate inspection system.
THE CHALLENGING OBSTACLES OF INSPECTING MEDICAL parts
There is a vast array of parts that a typical medical OEM manufactures and then needs to inspect. For example, bone plates are either flat or close-toflat, whereas knee implants are complex, full-contoured 3D parts. A single family of parts, such as bone screws, comes in many sizes ranging from very small to large, and in dramatically different geometries. Each part needs to be accurately and quickly inspected in order to be cost efficient and meet specified regulations.
Another concern for manufacturers is the type of material that is used. Implants, for example, can be made of different materials. Many metallic implants are made out of titanium due to its resistance to corrosion from bodily fluids, bio-inertness, capacity for osseointegration, and high fatigue limit. However, other metals-such as iron, cobalt, chromium and tantalum-are also frequently used. Furthermore, specialized plastics such as high-density polyethylene are generally the most common material used for parts designed to be a replacement for cartilage. All of these materials present different appearances to visual inspection systems, making the task of inspection all the more challenging.
To further complicate the inspection process, parts made out of the same material can appear very different when they have varying surface finishes. For example,...