The ability to “see through” a solid object was once thought to be a tool of the future, or a power belonging to Superman–but the technology is here today, and more widespread and accessible than you may have thought.
Until recently, the technology of CT imaging was only available for use in medical settings. Over the last several years, it has found a new home in the world of manufacturing, and is opening up myriad opportunities never before available.
CT, or Computed Tomography, is now commonly used in various industrial metrology settings, both in the lab and online or inline for product evaluation and packaging integrity assessment. The main advantage is that it allows the inspection of a part’s interior structure or a package’s closure functionality without causing any harm or destruction to the objects themselves.
the same type of technology as CT scanners in hospitals and doctors’ offices–taking multiple readings from various angles and converting the CT grey scale images into voxel-based 3-dimensional point clouds. Once the CT scanner generates the point cloud, a specialist can generate a CAD-to-part comparison map, construct a 3D model of the part, or reverse engineer the part to suit their needs. In the packaging world, especially where pharmaceutical or personal products are concerned, this ability is paramount. High-speed scanning inline, for example, can examine the seals on pill bottles for airtight quality assurance, while online or lab scanning can instantly compare a manufactured product to the CAD program in various ways.
Industrial scanners offer a multitude of advantages, such as: obtaining internal structure of an object non-destructively, validating extremely accurate internal dimensions, allowing comparison to reference models, no shaded zones, compatibility with all shapes and sizes, no post-processing work and extremely high-resolution imaging.
Some of the most common uses of 3D and now CT scanning in industrial metrology applications include:
There is a wide range of industrial scanning equipment styles and sizes available to suit different types of applications. Micro units in table top styles for lab use up to full industrial grade floor models for in-plant or in-process use, to portable measuring arms that can be used on the shop floor or out in the field are all available today, usually from a manufacturer or a service organization, for one-time contract use, with rent or lease-to-buy arrangements optional. Many of our customers, having used our services, subsequently purchase the equipment and training to add this high-end metrology to augment their inside CMM or test lab, for example. In the case of larger production facilities, we often see metrology today being integrated into the line for instant analysis of parts, whether molded, stamped, welded or otherwise fabricated, as well as packaged goods.
Typical CT scanners offer a wide range of measurement capabilities and features. Sizes start with small desktop models which meet the most stringent demands and measure the smallest 3D detail from 0.25µm. They can be equipped with different X-ray powers, from 160kV for nanometer resolution through 225 kV, 320 Watts to the highest power of 300 kV, 320 Watts.
Larger scanners are available for extremely fast CT data acquisition on workpieces up to 500 mm diameter and 600 mm in height, weighing up to 50 kg (110 lbs.). Typical functions performed on this type of system might include 3D analysis of a scanned turbine blade, automatic pour porosity volume analysis on an aluminum casting and 3D measurements with nominal-actual CAD comparisons on a machined aluminum cylinder head.
The future of industrial scanning holds unlimited possibilities, especially when combined with 3D printing or other additive manufacturing methods. As improvements are made in technology and performance and costs continue to decrease, the industrial scanning industry is preparing for explosive growth in the next 5-10 years.
Author: Dean Solberg Co-Founder of Exact Metrology
For more information: www.exactmetrology.com