At PAI Industries we strive to provide 100% customer satisfaction with every product and service that we provide. Quality and performance are the most important aspects of our designs. In order to achieve these goals we identify ways to improve upon the design of the original equipment manufacturer (OEM) to ensure that the part’s performance meets and exceeds the demands of the market.

What the Market Was Saying

Feedback from PAI customers is encouraged in order to improve our products and to keep abreast of nuances in our different markets. Our goal is to provide solutions to our customers with our parts and services. A recent example of PAI’s innovative solution to a market problem dealt with the Detroit Diesel Series 60 exhaust manifold. We learned through customer feedback that the OE manifold was failing frequently. It’s design was susceptible to fracture in the middle of the center piece.

Figure 1 - OEM Manifold Indicating Fracture

The PAI Approach

PAI took on the task of solving the problem. The first steps in the process were to analyze input received from customers and then perform a detailed investigation of the product. Various tests were run to determine the root cause of the failure. It was concluded that a combination of factors was to blame. Temperatures within the manifold can reach 1200 degrees and weaken the metal. The weight of the turbo on top of the manifold coupled with cyclic thermal loading was causing fatigue fractures.

Our knowledge and experience in other engine technologies such as Mack, Volvo, Cummins and Caterpillar was instrumental in finding a solution. Using advanced CAD (Computer-Aided Design) software, our engineering department re-designed the center by adding a rib between the center sections. The extra reinforcement made it more robust and capable of withstanding the extreme operating conditions that exist in real-world applications.

Figure 2 - CAD Illustration of PAI’s Design

Don’t Just make It Better - Make It the Best

While our re-design of the center piece’s fracture location is enough to address the failure, our engineering team found that there were other aspects of the OEM design that could be improved upon. Using cutting edge CAE (Computer-Aided Engineering) and FEA (Finite Element Analysis) software, our engineering team simulated the flow of gas and heat, as well as thermal expansion of the entire manifold system, including the two side pieces. Our analysis concluded that by re-designing the way the three components mate and their internal channels we could reduce turbulence and improve flow. The end result was a design for an exhaust manifold that offers better performance and can stand up to the harsh conditions in the field.

Figure 3 - CAE Rendering of Exhaust Gas Flow

Prototype: From Concept to Reality

The first step toward bringing this design to life was to create a model out of plastic using 3D printing technology. Having a working 3D model allowed us to see details that were not apparent in the CAD model.

Several iterations of modifying the CAD model and making 3D prints took place until the manifold design was perfected – both virtually and in real space.

Figure 4 - 3D Printed Model

The next step was to manufacture the exhaust manifold. The team researched the qualities of various metal alloys and chose a composite that afforded strength above the extremely high temperatures which would be encountered in usage. This newly redesigned manifold was ‘exhaustively’ tested on an actual engine in our dynamometer. These real-world results matched our simulations in terms of fit and performance.

The Finished Product

In less than a year, PAI’s dedicated team of sales representatives, engineers, and manufacturing technicians identified a problem in the field and created an innovative solution for the market. The newly redesigned exhaust manifold consists of improved side and center sections for enhanced strength, gas flow, and overall performance.

Figure 5 - PAI’s Redesigned Detroit Diesel Series 60 Exhaust Manifold