Accurate Inspection of Internal Features

Accurate Inspection of Internal Features

CGI’s Pearl 3D scanning machines are now available through Shropshire-based company Plastic-IT, helping make this cost-effective and versatile measuring and inspection technology readily available for all OEMs across Europe.

The machines originate from the United States, the complete name of the founding company CGI (Capture Geometry Internally), alluding to the key use of the technology, namely the 100% accurate measurement and inspection of the internal and external geometries of plastic parts.

For OEMs, accessing this technology will not just provide unparalleled results in terms of accuracy, but also significant savings in the time and expense involved in inspecting plastic parts. It is ideally suited to personnel involved in first article inspection of injection moulded parts, reverse engineering, tooling qualifications, and failure analysis.

The easiest way to understand how the technology works is to imagine a rapid prototyping machine working in reverse, instead of building a part layer by layer, slicing it layer by layer, and capturing a series of 2D images of the sliced part. The plastic components to be inspected are “potted” in a slow curing resin before the slicing process begins, and the nature of the process means that any part — however complex the internal and external geometries — can be inspected.

The process uses Spec.Check proprietry software to cross-section parts anywhere and in any geometry. Uniquely, the technology is also able to measure and inspect assembled components, and there are no restrictions in terms of the plastic materials and types of fillers that can be measured.

Once set in motion, the fully automated CGI 3D scanner can be left unattended, making the inspection of injection moulded parts and components faster and less expensive. It is this automation that is a key difference between the 3D scanning technology and other inspection processes, as is the 100% accuracy and repeatability of the process.

The difficulty or expense of using the only other technology able to produce accurate 3D data for internal geometries (CT scanning), often leads manufacturers to find ways to avoid having to measure the internals of complex plastic parts. The CGI 3D scanning technology — for the first time — makes the attainment of reliable and accurate internal inspection open to all OEMs, it being about a tenth the price of a CT scanner, and requiring much reduced operator skill than alternative measuring technologies.

When compared with the use of CMMs, the ease-of-use of the 3D scanning technology becomes obvious. Unlike CMM inspections, when using the 3D scanning technology, there is no need for a time consuming, costly, and  robust inspection plan that identifies areas of potential trouble or interest. Also eliminated is the amount of educated “guess-work” about where problems are most likely to be detected before any actual inspection has taken place.

There is also no need for expensive part fixturing (which can affect the viability of measurements) before inspection. For 3D cross-sectional scanning, once potted, the part analysis produces a detailed point cloud which allows quality interrogations time and time again with no necessity for rescanning.

The CGI technology captures sharp corners, deep pockets, and internal geometry in a single scan. Its use eliminates the time-consuming requirement for post-process assembling of data to create a complete data set.

Where in-depth analysis of feature rich and complex parts are required, or measurement of multiple parts or assemblies is needed, the 3D scanning technology wins hands down. In addition, the use of measurement templates allows simple and repeatable checks of parts from multi-cavity tools or analysis of parts from different production batches.

As the drive for increased inspection capability for less and less cost intensifies across industry, more and more OEMs will be attracted to this innovative inspection tool. The marriage of a more complete inspection picture, flexibility in quality processes, lower inspection costs, and faster approval cycles (that mean reduced time-to-market) are nothing if not compelling. To ensure as many manufacturers as possible can access this innovative measuring and validation technology, Plastic-IT — as well as selling the CGI machines — also runs a bureau service so that OEMs can benefit from the technology before committing to purchase for in-house use.

For more information contact Richard Webster on t. +44 (0)7472 327166 or e.