Precision, eco-friendly sealing technology
21 November 2012
ElringKlinger (GB) has designed and developed a sophisticated precision manufacturing process to seal automotive parts, significantly increasing the production rate for these components, as well as reducing energy emissions and providing a potential replacement for traditional metal gaskets.
Perhaps best known for its heat shields and speciality gaskets, ElringKlinger (GB) has recently ploughed a significant percentage of its profits – some £250,000 in fact - into a research and development project that has enabled the in-house development of a fully automated cured-in-place (CIP) production line.
The Redcar based automotive parts manufacturer designed its CIP application process on site, developing the sequence programs and ultimately building a prototype system, which was used for extensive onsite testing.
The use of CIP technology is growing rapidly and this is not surprising, given the advantages of the process, including high precision, lower energy consumption, and space and waste reduction. In terms of productivity, the technique ticks all the boxes, while its many potential applications hold promise of considerable environmental waste savings for the engineering sector.
During the in-house prototype development, the firm’s engineers adapted a robotic dispensing unit to apply the sealant medium. They then analysed the capability of the new sealing paths against traditional manufacturing techniques to assess their ability to achieve the strict design parameters, and to refine the manufacturability of the design.
Significant R&D effort concentrated on achieving accuracy in the height of the FKM sealant, which was specified at 100 microns, +/-25 microns. A laser-based technique was developed to check the flatness of the casting before the sealant medium was applied via a pressure nozzle. Mike Swankie, ElringKlinger (GB)’s engineering manager takes up the story:
“It was a long process, initially using a robot to apply the medium; however, after many trials it was proven that the robot was not accurate enough to meet the tight specification. We had to consider a different method of applying the sealant medium and decided on an XYZ gantry driven by U-channel brushless linear servomotors - ideal for alignment and positioning.”
The equipment used on this line includes an AGS 10000 Series linear motor driven XYZ gantry, an EPD high pressure dispensing valve, a laser head, a curing oven, conveyor components, cooling system and camera-based detection system.
In total, the CIP technology at ElringKlinger’s Redcar site took three months to fully develop and install. It takes up just 64 square metres of space and operates using tunnel oven elements that heat the castings to 115oC. It is in operation eight hours a day producing 200,000 units a year - on average, 840 sealed engine castings daily.
The cured sealant is applied through a high pressure nozzle at an outstanding accuracy of 100 microns high and 4mm wide, within the controlled tolerance of +/- 25 microns. The company believes this achievement sets a benchmark for other UK based engineering firms undertaking this type of work, as well as creating a novel method of applying seals to engine castings and other automotive applications. Mike Swankie again:
“We are currently using the CIP process to produce high quality BMW engine castings. This is a highly effective system that completes a unit every 30 seconds so there is great potential for other applications to be incorporated in the production process.
“We are entering an exciting phase for the company with ambitious growth plans already underway. Now we are confident in the results of this technology, we hope to develop CIP further and have laid the foundations for UV technology.
“Using such advanced technology allows us to further develop our environmental responsiveness as the energy required for curing is less, meaning our carbon dioxide emissions are lower. The production line is also very effective in fulfilling the requirements of environment-related regulations and orders such as PRTR (Pollutant Release and Transfer Register) Law or ISO 14000.”