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GD&T and Customer Involvement at Embraer Create Incredible Aircraft

Embraer has Created New Interiors for Its Aircraft Using Dimensional Engineering and Strong Support from Customers

In Business Jet Interiors International, Embraer is featured in an article called jointeffort, discussing the new Legacy 450 and 500 and the efforts Embraer and its suppliers have put forth to completely redesign the aircrafts' interiors. This article briefly discusses some of the concepts put forth in jointeffort, but does not include customer data.

You can find the original article here on page 64:http://viewer.zmags.com/publication/e0f990f9#/e0f990f9/1

Quote 1 GDAs a key element to the process of creating these resplendent interiors, Embraer incorporated GD&T, Geometric Dimensiong and Tolerancing, that enables communication of key dimensional features throughout the organization. With GD&T, manufacturers and designers can clearly define dimensional specifications and measurement plans, thus allowing the manufacturers to build to the exact designs that Embraer conceived. 

Create Your Specifications Early

Example of an Overhead Bin SpecStudyWith tools like 3DCS, the GD&T can be optimized and tested, determining which areas will be problematic to manufacture and enabling designers to determine optimum design changes to solve those problems, all before production begins. 

In interiors, before the design even reaches the stage of simulation and testing, designers are able to create virtual Perceived Quality studies to deduce the quality objectives of the product. This, in addition to traditional prototyping, can give designers the opportunity to determine how the design specifications will affect the appearance of their product. With that in mind, the design can be optimized to be more easily manufactured, without the side effect of lowering the appearance of quality. 

describe the imageOptimize Your GD&T with Variation Analysis

As the objectives solidify, users can take advantage of 3DCS for Monte Carlo simulation to analyze variation. By creating thousands of 'digital prototypes', contributors to variation and key quality characteristics can easily be highlighted. Honing in on these areas, designers can make less important areas of the assembly easier to manufacture by loosening tolerances, within objective limits, and create measurement plans for the shop floor for the key quality characterisitcs, reducing the amount of data to be collected to just those areas that will most affect the assembly. These time and cost saving approaches, when conceived within the dimensional objectives, can be applied without affecting the perceived quality of the product. 

Variation analysis, including tolerance analysis, is the perfect opportunity to test your GD&T and determine design changes to accomodate sensitive areas. Simulating both tolerances and operations and processes on the assembly can determine how your fixturing, assembly and operations like welding and bolting, will stretch and change the geometry of your components. This is important in regards to your GD&T, as given tolerances can be compounded upon by additional variation not found in the manufacturing of the parts, but in the assembly process and tooling themselves. 

Establish GD&T Culture

It isn't enough to use GD&T at the front end of a product lifecycle. In order to realize the cost savings and time savings that GD&T entails, it has to be embraced by the entire culture. GD&T becomes the language of quality, which establishes clear features and methods of manufacturing, measuring and controlling the parts. The best measurement plans are worthless if every supplier measures different features from different datums because of confusing GD&T or lack of experience with GD&T. In order to control quality to the degree that Embraer has acheived, GD&T understanding and use has to be established across the entire enterprise. 

This can be done a number of different ways. One method encountered was the training of key managers to act as champions and retrainers. This creates experts across different disciplines who are all trained together, establishing a group understanding and standardized set of principles that can then be disseminated throughout the organization. 

Executive Commitment

It is key for a company's executive body to embrace and champion the use of GD&T. Whether trained in GD&T or not, it is important that the executives understand the benefits and adamantly hold their managers to the use of GD&T. In this way, the importance of proper use of GD&T can be held firm from the top down. In essence, without strong executive backing, GD&T cannot be successfully implemented. 

Tracking and Monitoring Quality

So your company has implemented six sigma initiatives and are using GD&T as a method of communicating key quality information throughout the organization. Its time to find out if it has accomplished anything. So,

How do you know if it worked?

30 measure report graphics page qdmYou track it.

Easy to say, hard to do. Very hard to do actually. As mentioned previously, tracking quality across a global enterprise, especially with large assemblies like those found in aircraft, can be a truly daunting feat. 

GD&T becomes the vehicle to begin the process of determing the success or failure of quality initiatives. By using GD&T, key quality characteristics can be called out, with datums to determine 0,0 and origin. This tells suppliers and engineers which features to measure, and from where. As simple as it sounds, this is a big deal. Oftentimes, suppliers are not clearly told which features are critical to the larger assembly, or how specifically to measure their parts for the customers. This can create a great deal of problems. With good GD&T, engineers at the OEM and suppliers can both measure the same features to establish part quality and conformance to specs. This will ensure that suppliers create the parts that OEM's need, and help suppliers reduce problems from issues that may not have been communicated properly from their customers. 

There is nothing worse than the call that tells you your parts are not to spec, when you just finished measuring and confirming that they are to spec. Something is off, and it usually stems from the communication of measurement plans and key features. This can be solved with GD&T. 

In short, the use of GD&T and variation analysis together are powerful enablers of more efficient and higher quality manufacturing, at lower cost than traditional quality control methods. 

Interested in learning more about GD&T, let DCS know!

With ASME certified experts in GD&T, DCS can provide both training and consulting for GD&T, and can answer your questions. 

 

Topics: CATIA 3DCS Tolerance Analysis