The Appliance of Science

EJOT UK’s in-depth materials knowledge is driving improved fastener solutions.

One of the ways that EJOT UK is raising the bar on the quality and performance of its fastening solutions is by developing its materials science expertise, supported by state-of-the-art equipment within its Applitec Centre.

This is important because it enables its fastener specialists to maximise their understanding of the materials used in the construction of building envelopes, and how the fixings interact with them to create secure joints that stand the test of time.

Taking the lead in this area of the Applitec Centre team’s work is Technical Manager Jon Knaggs, who originally joined EJOT in 2016 as an apprentice with an interest in developing a career in engineering. Since then, Jon has seized the opportunity to advance his knowledge as part of EJOT’s training and development programme, and this has included studying and achieving a BEng in material science technologies.

This academic study at Sheffield Hallam University was the catalyst for Jon to develop his specialist interest concerned with the analysis and testing of the materials that are used in EJOT fasteners – chiefly metals and plastics. And today he is very much EJOT UK’s resident materials specialist, as well as being responsible for the industrial lightweight and CROSSFIX product segments.
 

Interpreting technical standards for maximum customer benefit

Jon’s role includes ensuring the company’s technical literature and testing procedures are aligned with modern engineering standards and provisions. His work is also important to influence new projects as well as the overall direction of projects being undertaken here in the UK.
Along with his colleagues in the technical team, a key area of Jon’s work is handling a wide variety of customer requests for assistance, ranging from technical data and support for testing to investigating site issues and advising on fastener selection. An increasingly large proportion of his work, however, involves testing as part of longer term projects which aim to continuously improve the performance and quality of EJOT fasteners.

Jon says: “The long term objective for developing my role at EJOT UK is to ensure that we are offering the highest possible technical service to customers. Whether it’s through specification, testing or training, our goal is not only to maintain our position but to push fastening technology and services to new levels of engineering and science. What is key for me is to always be looking at how best to make complex and relevant technical data easy to understand and accessible to everyone.”
 

Metal focus

Jon’s interest in metallurgy and the knowledge he has amassed relating to metals is crucially important in helping customers achieve the strongest, most reliable joining of two materials. He explains:

“Before we consider the strength of a fastener, we have to understand metals. Whilst steel and aluminium alloys used in construction are very well controlled and documented in terms of production and maintenance of minimum strength properties, continuous testing is essential to check for variability.”

Despite there being very well established International Provisions, such as ENs, ASTMs and AS/NZS relating to the strength characteristics of steels and aluminiums, EJOT’s Applitec Centre has been equipped with world-class equipment to ensure the team can do its own materials tensile testing. The laboratory environment that has been created enables the team to comprehensively check that EJOT fasteners will perform better than the calculations provided within Eurocodes.

Testing beyond the norm

In terms of mechanical testing, Jon and his colleagues are able to perform pull-out or withdrawal testing, pull-over testing, shear testing, and also cyclic fatigue testing.

The EJOT Applitec Centre is equipped with a range of advanced machines purpose-designed to conduct testing of fasteners to a high degree of accuracy. This includes being able to determine the thickness of the coating on galvanised sections, which is a crucial factor in characterising the mechanical performance of fastenings, using a laboratory grade XRF (X-Ray fluorescence) machine.

Jon continues: “If we're doing a shear test there are two pieces of metal that we are connecting. So, we check both. When we know the thickness and the strength, we can then conduct a pull out test.

“To conduct the shear test, we fix the two metals together, load them into our extensometer and pull them apart. But because we’ve gone to such lengths to assess the metal characteristics beforehand, the results from the shear test are extremely reliable.”

Confirming the strength of metals is one of the ways EJOT takes a holistic approach to providing evidence of the fastener’s performance and expanding on what is stated in an ETA.

Jon adds: “An ETA will never be able to cover every application, so it is common for customers to ask, ‘will this fastener work in this situation?’ – and that is something that our team will always seek to answer through our experience and test data.

“We have to think not just about the fastener, but what our customers are doing with it. And identify what the differences are between the performance criteria published in the ETA and the information that an engineer actually wants. This may require testing in a different way to get the required data, particularly in projects where there is something slightly more unusual.”

Utilising advanced technology to provide unrivalled customer support

One of the key reasons why Jon and the team can provide such detailed reports is due to the quality of the equipment available within the Applitec Centre.

EJOT UK continuously invests to give the technical team the tools to do their work to industry-leading standards, and that was the rationale for commissioning a special device for its extensometer to measure tensile strength. This enables the exact testing of stress versus strain in materials, as well as measuring the brittleness and ductility of materials – this is important because a material which is too brittle may indicate the potential for sudden failure.

Whilst many larger systems manufacturers will have the resources to conduct their own testing, many people involved at all stages of the building envelope supply chain will not. That means EJOT offers a service to help architects, structural engineers and contractors meet performance targets and deliver high quality buildings.

Jon concludes: “Technology has always been at the forefront of what we do at EJOT and the Applitec team will always look at ways we can apply even more advanced laboratory apparatus and to strive for even greater technical excellence from our team.”