Given the European Union’s CO2 emission targets for 2021, it’s no surprise that the biggest slice of the European automotive industry’s budget has been ploughed into fuel efficiency technology since targets were first rubberstamped. Much of this investment is driven by the EU’s mandatory targets to ensure that, by 2021, new car fleets do not emit more than an average 95 grams of CO2 per kilometre.
As originators of fastening technology and with an association to the global automotive industry stretching back some decades, EJOT is one major company where the development of products and fastening systems has been instrumental in providing solutions to these challenges. Engineers at EJOT’s research and development wing, EJOT Applitec, have consistently partnered with automotive engineers from all corners of the globe to develop sophisticated thread-forming products that create high performance joints in virtually any metal or thermoplastic application.
Prestigious to practical
These products are found in up to eight different application areas on all types of vehicle manufactured throughout the world today; from the niche and prestigious, to the practical and mass produced. Though each fastening product has been engineered to provide performance benefits into specific materials, they each share the common benefits of either reducing weight by eliminating unnecessary components within the traditional assembly process or provide a strength of joint that, the company states, cannot be achieved by traditional fastening products.
Steve Wynn is EJOT’s sales manager for industrial fastenings, in the UK. In the build-up to Automechanika’s recent inaugural exhibition in Birmingham, FAST asked him to walk us through an overview of some of the EJOT products contributing to the drive for lighter vehicle assembly, starting with the area of chassis assembly, known throughout the automotive world as ‘body-in-white’. Here is his take on this.
EJOT ALtracs Plus
Developed specifically for use with aluminium and magnesium, the ALtracs Plus screw is designed to deliver a high strength of joint, whilst fixing directly into pre-cast holes. A typical example would be an electrical motor hosing assembly. A reduction of assembly components and thereby costs are very obvious benefits.
EJOT SHEETtracs
The push towards overall weight reduction means that reduced gauge sheet metal is now commonly used throughout vehicle construction and in many cases is thinner than the pitch of a standard sheet metal screw.
EJOT FDS: High strength sheet metal joints with no pilot hole
The FDS screw delivers the same application benefits as SHEETtracs, but introduces the possibility of eliminating the pre-drilled pilot hole.
EJOT EJOWELD: Joining light weight materials to thin sheet boron steel
Five years in development with one of the world’s largest automotive manufacturers, the EJOWELD process is arguably the most positive response to market demands for lighter vehicles, Wynn argues.
EJOT Delta PT
A direct progression of the original EJOT PT screw, Delta PT also has industry-wide recognition as the leading solution for direct assembly into thermoplastics. Its thread geometry creates low surface pressure whilst delivering high clamp loads, even in thin walled assemblies.
Delta PTP
Taking the overall weight reduction programme a stage further, EJOT has introduced an innovative plastic version of the metal Delta PT screw: Delta PTP. Comments Wynn: “Offering the same key benefits as its metal counterpart, this plastic version has been developed for applications where the material being thread-formed into has lower strength properties than the fastener itself. It therefore makes sense to match the screw material and the material to be fastened.” Manufactured from EMS Grivory HTV 5H1, the EOT Delta PT-P now makes it practical for unreinforced plastic to be commercially viable for the self-tapping assembly processes, he adds.
EJOT EPPsys
Foamed components are obviously integral to the overall steer towards lighter vehicles. In response to this, the EJOT EPPsys – or EPP System – has been developed to fasten assembly parts to foamed components, typically expanded polypropylene (EPP).
“As part of a broad application-specific product range, EJOT has developed the EPPsys RSD – a unique boss that provides highly effective fastening for EPP foams and honeycomb elements via a friction-welding process that leaves the product embedded within the EPP foam,” he states.
EJOT Applitec
Key to EJOT products delivering real-time solutions and assisting weight-reduction programmes for automotive manufacturers and first tier OEMs is the group’s worldwide commitment to ‘application technology’ or, to use its branded title, ‘EJOT Applitec’.
“The structure of EJOT worldwide and its support in developing solutions means we have in place a global knowledge pool of fastening expertise at every stage of the process – from concept to prototype to manufacture to assembly,” Wynn points out. “Given that, broadly speaking, the development of a product represents around 10% of the overall cost and determines about 70% of the final product’s cost. That means, for weight-reduction solutions to be viable, the joining technology is critical – and all too often overlooked at conceptual stages.”
