The relatively high expense associated with updating or purchasing software to automate the process is one of the main reasons why more aerospace manufacturers have not adopted PMI.
FREMONT, CA: Programming from a computer-aided design (CAD) model instead of utilizing automated tools to eliminate ambiguity to decode tolerancing, features, and characteristics have proven to be the most challenging aspect of quality control for aerospace manufacturing. The design production intends to incorporate product manufacturing information (PMI) into the model. However, many providers continue to program inspection equipment without a CAD model or CAD with PMI, leaving room for typos and misinterpretations.
The relatively high expense associated with updating or purchasing software to automate the process is one of the main reasons why more aerospace manufacturers have not adopted PMI. CAD is an open architecture in the public domain. Still, it must rely on the original CAD company for export, and different CAD companies develop their software for CAD development. Suppliers in the aerospace business must select tools, how data will be transmitted, and features and properties.
Stay ahead of the industry with exclusive feature stories on the top companies, expert insights and the latest news delivered straight to your inbox. Subscribe today.
Leaders are reluctant to enable their programs to be exported as a neutral file compatible with various measurement methods, such as EMF and laser systems. They would rather sell their CAD software, the aircraft sector standard. The software may be more challenging to master, but most aerospace engineers are already familiar with it. Typically, large aerospace businesses utilize software from prominent providers – the first to provide the majority of capabilities required for aircraft manufacturing.
In order to avoid quality variations in the aerospace industry, developers of measurement equipment take into account the various software offers so that all versions can support them. Specific tolerance parameters are accepted or unsupported inside the CAD model but not within the PMI data. Typical applications cannot interpret a graphic image. It is necessary to manually add data to the PMI file using other software applications, resulting in extreme variability in what supports the PMI side of the equation.
Although tolerancing characteristic information in a CAD model is not always required, the examination requires data. If they were to ask CAD vendors and measuring firms utilizing their software how much inspection data they support, they might discover that it ranges from 50 to 60 percent. As CAD tools did not include GD&T error checking, the biggest issue with GD&T tolerances is how engineers interpret them and how they are expressed on drawings.
