Get into the groove 26 October 2020

APM Hexseal designs and manufactures innovative and customisable sealing solutions that offer bidirectional sealing protection, preventing contamination or leakages from either side of the enclosed space. Here, the company offers a review of sealing hardware grooves and its processes.

What is the groove?

The groove - the concave space located beneath the head of the screw or bolt and above the threads on the nut - has a specific geometry that holds sealing rings or elastomers securely in place as the fastener is tightened. A well engineered groove is critical to the ability of the fastener’s sealing ring to compress properly upon tightening, allowing an airtight, leak-proof barrier to form between the groove and the mating surface.

Why get into the groove?

In industrial applications, sealing hardware is essential for securely fastening components within a system while simultaneously blocking contaminants from entering or exiting the sealed space.

Decades of design and manufacturing experience combined with a fully outfitted machine shop make APM Hexseal uniquely qualified to provide intelligently designed sealing solutions for a variety of mission critical and sensitive applications. When partnering with APM for your sealing needs, you can expect the following:

Superior sealing capabilities

APM Hexseal’s engineers, designers, and manufacturers work together to create exceptional products that are built to withstand a variety of harsh operating conditions and hostile environments. Its screws, bolts, and other fasteners are designed with built-in grooves that allow sealing elements to fit snugly and precisely under the fastener head. Seelnuts® contain a custom groove that enables moulding of the elastomer directly into the threads, providing a superior and long-lasting seal. The design helps create a tight seal that confines the contents of your operations while preventing external contaminants or debris from entering.

Uncompromised fastener integrity

Making sure the integrity of the fastener remains fully intact during the fabrication process is essential for achieving reliable sealing and fastening performance from the hardware.

Versatile sealing solutions provide dependable protection for everything from food and beverage processing equipment to electronic components and hydraulic systems.

High-tech sealing components are also available, by request, with FDA approved silicone to best support equipment used in sensitive applications, such as medical and pharmaceutical applications. With APM’s products the hardware’s integrity is maintained by incorporating the groove into the actual manufacturing process using cold forming techniques.

Wide range of applications

APM’s versatile sealing solutions provide dependable protection for everything from food and beverage processing equipment to electronic components and hydraulic systems. High-tech sealing components are also available, by request, with FDA approved silicone to best support equipment used in sensitive applications, such as medical and pharmaceutical applications.

Customised for an application

Selecting the right fastener with the appropriate groove geometry is essential to the hardware’s ability to seal properly. The exact parameters of a fastener’s groove will depend on multiple factors, such as the screw size and the panel cut-out. To make sure our hardware can provide the best possible seal, we make individualised recommendations based on panel characteristics, clearance holes, and other variables related to your specific application. We can customise virtually any aspect to the fastener or sealing element, including:

  • Fastener material - while most of our standard fasteners are manufactured using stainless steel, APM can work with a variety of other metals depending on specific needs.
  • Sealing ring material - sealing rings can be moulded from a wide range of elastomers, allowing the choosing of a material based on the specific conditions the fastener will encounter in applications. The colour of the elastomer can be customised as well.
  • Value-added design features and finishes - fasteners can be made to include various locking features, including self-locking pallets, strips, and patches. APM also offers a range of paint and finish options to enhance the final product’s functionality or aesthetic appeal.

Groove considerations

When choosing or designing sealing hardware for a specific application, there are several factors that should be considered to make sure the final product performs as intended. To form a proper seal, the elastomeric sealing element of the fastener must be able to deform by being compressed or stretched in various ways.

The diameter, depth, and width of a fastener’s groove will determine the sealing ring’s ability to be compressed properly against the mating surface to provide an adequate seal. Because of this, proper groove design plays a major role in the overall sealing performance of the hardware.

The exact features of a groove will depend on the overall size and style of the fastener, as well as the characteristics of the mounting panel that will be used. One of the most important design considerations is making sure the groove can be sized appropriately for the application without causing damage to the screw’s integrity.

A common mistake in fastener design is to allow the undercut to penetrate too deeply into the shank, causing the head of the fastener to break off when drilled into a surface. The engineers at APM Hexseal possess the expertise to prevent these types of failures, creating custom sealing hardware with expertly designed grooves that can ensure success in each application.

APM Hexseal’s sealing hardware

APM Hexseal’s sealing hardware is built to provide reliable, long-lasting protection in virtually any application or environment. Our reusable self-sealing fasteners can block or contain liquids, lubricants, gases, and dust, making them perfect for protecting and confining sensitive materials and equipment. The fastener’s tight seal prevents contaminants from seeping into or out of the sealed environment through small gaps between the screw and the mating surface.

The unique reusability feature makes our fasteners an ideal choice for applications that require frequent access or maintenance. Being resistant to vibrations, our hardware is also able to withstand repeated exposure to shaking or jarring movements.  To guarantee exceptional sealing performance in all our products, our quality department meticulously inspects each component to make sure the specific design requirements and quality standards are met.

Our sealing hardware is built to withstand some of the toughest operating conditions and environments, including those encountered in various military applications. In accordance with NASM 82496 standards, our military-grade products are pressure and time tested in-house to make sure they can support the demanding nature of defense environments. Additionally, the majority of our sealing fasteners are UL recognized, making them a smart, economic solution for NEMA rated enclosures.

APM is ISO9001:2015 certified and complies with a variety of other industry standards, including Dodd-Frank, REACH, and RoHS. “As a leader in sealing technology, we have the experience and resources to help you find the right sealing product for your unique project. Have more questions about our specific capabilities or customisation options? Ask the experts at APM Hexseal today,” commented the company.

www.apmhexseal.com

Claire Aldridge Deputy Editor t: +44 (0) 1727 743 889

Having spent a decade in the fastener industry experiencing every facet – from steel mills, fastener manufacturers, wholesalers, distributors, as well as machinery builders and plating + coating companies, Claire has developed an in-depth knowledge of all things fasteners.

Alongside visiting numerous companies, exhibitions and conferences around the world, Claire has also interviewed high profile figures – focusing on key topics impacting the sector and making sure readers stay up to date with the latest developments within the industry.