The DL-series Plug: Sealing in Reliability
In hydraulics, innovative product design is motivated by the need for a new function to reduce pain points or improve a current solution. The Lee Company’s automotive customers have told us that sealing cross-drilled holes in aluminum manifolds is a function they all need. These customers also shared that they seek new sealing solutions to reduce costs and weight, increase reliability, and enable easier installation and verification processes. Cost reductions can be achieved for each piece and via process improvements.
For example, reducing scrap and rework and eliminating secondary processes such as adding sealants, which may cause additional failure modes, can make the installation process more efficient. Automotive manufacturers want solutions for both low-volume and high-volume production, so it is a challenging set of issues to solve. With these needs in mind, The Lee Company developed a product to satisfy these requirements.
The DL Series Plug (patent pending) was born. It is a single-piece, stainless-steel expansion plug engineered to provide leak-tight performance in aluminum housings without using threads, sealants, or O-rings. The plug uses The Lee Company’s drive locking technology to seal passages reliably for life. This new locking-end design includes features that can be used for 100% verification that the part is properly installed, improving reliability in both low- and high-volume applications. The shallow length of the plug also provides several benefits for designers, including saved space, reduced manifold size and weight, and minimized dead volume.
An ideal method for verifying part installation for low-volume applications is visual inspection. The DL Series Plug’s locking end includes an Installation Indicator feature that will visibly flare out radially to touch the aluminum housing 360° around the part when installed. When there is no gap between the part and the housing, the part is fully installed.
EXAMPLE OF HOW TO VISUALLY VERIFY INSTALLATION OF A LOCKING END WITH DRIVE LOCKING TECHNOLOGY IN AN ALUMINUM MANIFOLD
For high-volume production, where hydraulic presses can be used, customers can additionally monitor the force and tool travel during installation to verify that the correct amount of force has been applied to the part and the tool has traveled the correct distance. For the highest level of verification, an electric servo press – such as that made by Promess – can be used to provide detailed real-time force and displacement feedback.
With such a press, installers will know exactly when the part is fully installed. The visual indicator can also be inspected by a vision system. Having multiple ways to verify the critical assembly process enables manufacturers to select the most appropriate installation and verification processes for their application.
BLUE SHOWS THE FORCE DURING INSTALLATION AND THE RED THE DERIVATIVE OF THE BLUE CURVE, WHICH THE PROMESS SOFTWARE CALCULATES IN REAL TIME. PLOTTING THE DERIVATIVE VERSUS TIME CAN IDENTIFY INFLECTION POINTS, SUCH AS WHEN THE INSTALLATION INDICATOR IS FULLY SEATED AGAINST THE HOUSING WALL, VERIFYING PROPER INSTALLATION
Overall, the DL Series Plug helps automotive manufacturers reduce scrap, rework and labor costs while improving reliability and lowering their total installed costs. Thanks to its compact size, competitive price, and ease of automated installation, the DL Series Plug meets the stringent demands of the automotive industry. The DL Series Plug is ideally suited for all applications where performance, quality, and reliability are critical to success. The Drive Locking technology used in this new locking-end design can also be leveraged by The Lee Company’s other products, such as check valves, pressure relief valves, and restrictors to reduce costs for high-volume applications in aluminum.
