Innovative and proactive with a robust research and development programme underpinning all activities, NES is constantly exploring new techniques and seeking to develop new compounds.

Together with strong partnerships with trusted outsourced vendors, a Materials Manager dedicated to compound development and an experienced Technical Engineering department, NES is able to both develop and troubleshoot which ensures comprehensive and integrated solutions.

NES Value Proposition


Our capabilities are wide ranging and include:

  • Full turn key solution, concept to realisation
  • Rapid prototyping
  • In-house FEP/PFA Teflon™ extrusion, with in-house elastomeric core extrusion to facilitate NES Ncaps® manufacture from start to finish
  • Rubber to substrates bonding including; PTFE, PEEK, Titanium, Stainless steel, Aluminium, Brass
  • In-house tooling and grinding capabilities for smooth finishes and extra tight tolerances
  • Manufacture of VulcOrings, Custom Profiles and Inflatable Seals with a parent material and a 45 degree join, ensuring no loss of material characteristics across the join area and the strongest bond available
  • The sole use of a wide range of Western-sourced, exotic materials and Chemours licensee status assures the highest quality materials in NES products
  • BS, AS and JS standard size available plus bespoke sizes
  • ISO 7 Cleanroom Moulding & Extruding
  • ISO 6 Cleanroom Packaging

NES products are rigorously tested before delivery; all NES TECHNIFLATE® inflatable seals are tested to 1 bar, unsupported, to assure quality and mitigate failure.

Even when a very quick turnaround is required, as it often is, quality is never compromised.

Polymers Science

NES’s expertise in material behaviour ensures that we can design and develop solutions that exceed the most demanding technical requirements.

Our products utilise custom and proprietary compound formulations which have been developed and refined over a many years by NES’ technical team; resources include over 350 different rubber compound grades and are we constantly developing new materials to meet specific  technical requirements.

An in-house testing and development laboratory is vital to our customer support and we offer:

  • Chemical validation to specifications
  • Physical validation to specifications
  • Colour matching
  • Industry certifications and approvals where appropriate

Rubber to Metal Bonding

Many claim to be good at rubber to metal bonding, but few actually are!

Northern Engineering (Sheffield) Ltd (NES) has developed its rubber to metal bonding capability over many years and has experience of several metals in combination with a wide variety of rubber materials.

Working closely with some key customers, NES has developed a series of rubber and titanium components for demanding semi-con applications.

With expertise in mould-tooling design, surface preparation processes, primer selection and curing configuration (temperature, pressure and duration NES has impressive credibility in markets that require strong rubber to titanium bonding, such as the wider semi-con and Airspace & Defence industries.

Utilising the skill of our inhouse engineering team to overcome the natural incompatibility of rubber and metal, NES achieves components which attain tight dimensional tolerances and are strong enough to withstand stringent dynamic and static (destructive) testing.

Each component is matched to a full set of recorded measurement data, and carefully cleaned in NES’ clean-room packing environment prior to shipping.

Sub Assembly

Northern Engineering (Sheffield) Ltd (NES) produces high quality custom sub-assembled parts.

NES can offer its customers an extensive range of sub-assembly components. Typical components include ducting for environmental control systems and auxiliary power units (APUs). Our engineered approach allows us to develop products with single architecture to multi-branch architecture using our highly skilled hand fabrication techniques.

Our extensive sub-assembly facilities are located within a clean environment, this environment allows us to offer products that meet and exceed our customers’ requirements.

Special Moulding

Northern Engineering (Sheffield) Ltd (NES) produces custom made special mouldings using our in house moulding facilities. Our moulding facilities are capable of manufacturing small micro mouldings that are only a few millimetres in size up to large mouldings with a size range of 1000mm.

Moulded seals produced by NES are used in a wide range of different markets; these include the semi con market, aerospace market, defence market, pharmaceutical market and many others.

NES moulded seals are fabricated from specially formulated Elastomers tailored to exact project requirements. Our moulded seals work in the most demanding of environments including vacuum, high pressure, extreme hot or cold and fuel or chemically corrosive environments.


With a highly developed in-house extrusion production facility, extruded seals are a particular area of expertise for NES.

We produce extruded seals across a wide spectrum of profiles and in many different rubber compounds. Colour matching and flame retardant materials are a particular area of specialisation.

Managing the extrusion production facility in the same way as an external supplier ensures that our extrusion production always keeps pace with other production requirements; extruded seals produced by NES are used in the OEM and MRO sectors.

In aerospace for example, NES elastomeric seals can be found as aircraft baggage door seals, cockpit window seals, galley seals and spoiler seals.

NES seals are fabricated from specially formulated elastomers, tailored to exact project requirements.  NES can extrude seals that perform in demanding and varied environments including vacuum, high pressure, extreme hot or cold and fuel and chemically corrosive environments.

Uniquely, NES is able to produce high quality seals as small as 1.08mm, and as a large as 70.00mm in cross-section.

Tubing made from Teflon™

  • In-house and highly developed
  • Allows NES to extrude the jacket, as well as the elastomeric core, for our Ncaps, allowing full dimension control with a zero tolerance of air gaps, which mitigates failure risk and also gives enhanced compression set performance
  • Is used both as a component to an NES Ncap® but is also a stand alone product
  • High quality material
  • Experienced & highly skilled team

CAD/DPD Design & Bespoke Engineering

Whatever the project, NES aims to be easy to work with, offering a ‘start to finish approach’ which sees us working in close partnership with customers.

CAD (Computer Aided Design) and DPD (Distributed Participatory Design) ensures that we can proactively assist with product development, refinement and ‘trouble shooting’.

Our Product Development team has extensive experience, working with customers on diverse projects with their own unique challenges.

As a major exporter, NES is accustomed to and comfortable with dealing with development challenges arising from different geographical areas.

NES is currently able to read drawings in the following formats.

  • STP
  • IGES
  • ACIS
  • STL
  • CGR
  • DXF
  • SWG

Testing & Evaluation

At NES we believe in putting ourselves to the test, constantly pushing the boundaries of our expertise and seeking to enhance our processes.

Our in-house testing facilities are stringent and exhaustive, located in a providing customers with enhanced development support during co-development projects and ensuring peace of mind regarding quality of product and performance.

Testing processes include:

  • SG Testing
  • Indentation testing to ASTM Shore A
  • Elongation at break testing
  • MPA testing
  • Stress testing
  • Peel testing
  • Immersion testing
  • Compression set testing
  • Oil Immersion testing
  • Heat age testing
  • Pressure testing
  • Submerged cycle inflation testing
  • Non submerged cycle inflation testing
  • Destruction testing

Teflon™ is a trademark of The Chemours Company FC, LLC used under licence by Integrated Polymer Solutions.