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Dependable New Method For Automotive Companies to Seal Cross-Drilled Holes & Reduce Costs

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.

DL Series Plug Visual Verification

IMAGE OF VISION SYSTEM INSPECTING INSTALLATION INDICATOR FEATURE FOR COMPLETE INSTALLATION

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.

Visually Verify Proper Install of DL Series Plug

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.

Installation Curve of DL Series Plug with Promess Servo Press

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.

LEARN MORE ABOUT DL SERIES PLUGS

The DL Series Plug is a single-piece, stainless-steel expansion plug engineered to create a leak-tight seal in aluminum housings without the use of threads, sealants, or O-rings. This plug’s Drive Locking® technology is purposely designed to facilitate reliable automated installation and verification processes, allowing customers to reduce scrap and labor costs while improving the reliability of their production processes. The Lee DL Series Plugs range in size from 4 mm to 8 mm.

Further reference

The Lee Plug is simply the most successful method to seal drilled holes for critical applications. Over 150 million are used on aircraft, missiles, spacecraft, machine tools, downhole oil tools, molds – anything that requires a permanent leak-proof seal.

Lee Plugs are manufactured to exacting tolerances. Every process is precisely controlled. Critical dimensions are 100% checked, and others are statistically checked. All plugs and pins are 100% visually inspected. In addition, every lot of Lee Pins and Plugs is production acceptance tested. A representative sample of the mating pin or plug is performance tested to a Lee Company process specification for installation, leakage, pin retention, proof pressure, and thermal stability. Two certificates of performance (one for the pin lot and one for the plug lot) accompany every shipment of Lee Plugs. Go deeper into the precision of The Lee Plug with The Principle of the Lee Plug Performance.

A plug solution Case study from the lee company

A leading automotive manufacturer struggled to find a cost-effective solution to reliably seal cross-drilled holes in transmissions and engines. The problem resulted in customer leakage complaints, high warranty costs, and internal rework costs, ultimately costing them millions of dollars and jeopardizing their reputation. Read more about their challenge and how The Lee Company plugs were the perfect solution: Helping One of the Largest Automotive Manufacturers Save Their Reputation and Dollars 

The original Feature

The following was first featured in Automotive Powertrain Technology International and Transmission Technology International.

 

 

 

 

 

 

 

 

 

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