Aerospace
Ceramic Seals Limited is one of the few UK-based manufacturers specialising in ceramic-to-metal sealing solutions for the aerospace sector. With over 20 years of experience, we have supported a wide range of aerospace programmes and continue to supply mission-critical components for both civil and defence applications. Our assemblies have been successfully deployed on in-service aircraft for decades, trusted by leading OEMs including GE, AEM, and MBDA.
We deliver fully managed, end-to-end manufacturing solutions, combining design expertise, robust quality systems, and scalable production capacity. Our components meet the stringent demands of high-altitude, high-vibration, and temperature-variable aerospace environments, where reliability and performance are paramount.
Certified to AS9100, our processes are built on continuous improvement, precision, and traceability. We are committed to providing exceptional service, combining technical authority with a flexible, customer-focused approach that ensures quality and value at every stage of the programme lifecycle.
01 - FAQs
How long have you supplied into the aerospace industry?
We achieved AS9100 accreditation in early 2009 and continue to refine and improve our manufacturing processes in line with the most recent standard requirements.
Do you support first article inspection (FAI) and full documentation in line with AS9100?
We offer First Article Inspection (FAI) for new or modified parts, providing full documentation and validation of key characteristics as specified by the customer. All FAIRs are carried out in accordance with current AS9100 requirements.
Do you hold NADCAP accreditation?
While we do not currently hold NADCAP accreditation for our in-house processes, we have a strong understanding of the associated supply chain requirements and work with approved suppliers to carry out any necessary accredited processes.
Defence
Ceramic Seals Limited has a long-standing history of supplying critical components to the defence sector, including assemblies used in nuclear submarines, military aircraft, and classified systems. Our ceramic-to-metal feedthroughs and isolators are engineered for durability, reliability, and performance in extreme environments. We operate under strict security protocols and comply with ITAR regulations to ensure full adherence to the sensitive nature of defence applications. With in-house control over design, manufacture, and testing, we deliver robust, traceable solutions that meet the exacting standards of this highly regulated industry, where component failure is not an option.
01 - FAQs
Can you provide full documentation and traceability for defence procurement?
Yes, we can provide Certificates of Conformance for both products and materials, ensuring full traceability through our internally controlled documentation system.
Can you support long product lifecycles and legacy system replacements?
Our design records date back to the 1950s, with over 70 years of archived drawings. We maintain full historical design data, allowing us to support legacy parts with the same precision and reliability as any current product.
Medical
Ceramic Seals Limited has an established track record of supplying high-reliability ceramic-to-metal assemblies to the medical sector. Our components are used in a wide range of applications, including surgical tools, diagnostic systems, medical imaging equipment, and optical instruments. We manufacture complex brazed assemblies that offer excellent electrical insulation, hermetic sealing, and biocompatibility, which are key requirements in critical healthcare environments.
Our high-purity medical-grade ceramics are trusted by leading device manufacturers such as Siemens and Smith & Nephew, valued for their strength, thermal stability, and reliability. With in-house design and manufacturing expertise, we support both standard and custom requirements, from power feedthroughs in imaging systems to precision optical assemblies used in surgical cameras. Every component is produced under rigorous quality controls to ensure safety, performance, and compliance with industry standards.
01 - FAQs
Are your components compatible with sterilisation processes such as autoclaving?
Our assemblies are capable of withstanding repeated autoclave cycles, making them well suited for medical applications that require rigorous sterilisation and cleaning protocols.
Do you offer biocompatible materials or surface finishes?
We work with a wide range of materials, including biocompatible options, and are happy to discuss specific application requirements to ensure the most suitable solution.
Research
Ceramic Seals Limited has a long-standing history of collaboration with leading international research institutions, including CERN, STFC, DESY, Nikhef, and numerous universities and national laboratories. We support the development of advanced components used in cutting-edge scientific equipment, ranging from particle accelerators and cryogenic systems to vacuum chambers and associated instrumentation.
Our facility is well-equipped to undertake small-scale R&D programmes, offering integrated support across design, manufacturing, testing, and pre-production scaling. We apply our expertise in ceramic-to-metal sealing, vacuum compatibility, and high-voltage isolation to ensure components not only meet stringent performance specifications but are also designed with manufacturability and scalability in mind.
Using industry leading design tools, and AS9100-compliant design control processes, we support our clients from initial concept through to reliable, production-ready solutions. This approach helps bridge the gap between prototype development and full-scale implementation in complex research environments that typically require fully bespoke solutions.
01 - FAQs
Can you support low-volume prototype development with design input?
Absolutely! We specialise in low-volume production and support the development of solutions tailored to your specific system requirements. Whether adapting an existing product or creating something entirely bespoke, we’re here to help.
Have your components been used in cryogenic environments?
Yes, our production materials offer excellent thermal shock resistance, enabling us to manufacture dedicated isolators specifically designed for use in cryogenic applications.
Vacuum
Ceramic Seals Limited operates extensively within the vacuum industry, supplying components specifically engineered for use in high and ultra-high vacuum (UHV) environments. Hermeticity is at the core of every product we manufacture. Each seal, feedthrough, or isolator is designed to deliver reliable, leak-tight performance under extreme pressure differentials, ensuring long-term stability and maintaining system integrity.
Our assemblies achieve a minimum leak rates below 10⁻⁹ mbar l/s, and are verified using helium mass spectrometry. This level of performance allows direct integration into vacuum systems where maintaining a clean, gas-tight barrier is critical; such as in electron microscopy, ion implantation, cryogenic research, and semiconductor processing.
Ceramic-to-metal sealing technology offers several advantages for vacuum applications, including excellent outgassing performance, thermal stability, and electrical isolation. We utilise materials such as alumina ceramics, Alloy 42 and stainless steel, selected for their thermal expansion compatibility and suitability in vacuum conditions.
01 - FAQs
What leak rate can your assemblies achieve for ultra-high vacuum applications?
All assemblies must meet a minimum leak rate of better than 10⁻⁹ mbar l/s to pass inspection. However, depending on the assembly size and configuration, we often achieve even lower leak rates.
Are your components compatible with bake-out procedures and vacuum cycling?
Yes, provided the assembly contains no polymer materials, bake-out temperatures of up to 450°C can be readily achieved.
What materials do you typically use to ensure low outgassing in vacuum systems?
All materials used are typically low outgassing, helping to maintain stable vacuum conditions and prevent contamination in sensitive environments.
Power Generation
Ceramic Seals Limited has been supporting the power generation industry for over two decades, delivering robust design, manufacturing, and testing solutions for high-reliability applications. Our ceramic-to-metal feedthroughs are inherently well suited to high-power and high-current environments, offering excellent electrical isolation, thermal stability, and hermetic sealing under demanding operating conditions.
Many of our standard product lines are directly applicable to power systems and can be deployed off the shelf. Where system-specific requirements arise, our in-house manufacturing capabilities allow for customisation through minor modifications to standard assemblies, ensuring compatibility without compromising lead times or performance.
We have supported a wide range of clients in the energy sector, including Jacobs UK (now Amentum Clean Energy), GE Energy (now GE Vernova), and Urenco. Our services range from design consultation and material selection to precision manufacturing and qualification testing, all backed by our ISO 9001 and AS9100 quality systems to ensure consistency, traceability, and long-term operational confidence.
01 - FAQs
Are your feedthroughs suitable for high-current or high-voltage isolation in harsh environments?
Yes, we offer a wide range of off-the-shelf assemblies with varying voltage and current ratings. Multiple material configurations are also available to meet requirements such as corrosion resistance or low magnetic permeability, ensuring long-term integrity in demanding environments.
Can standard components be modified to fit system-specific geometries or housings?
Absolutely! We can modify any of our standard assemblies or develop entirely bespoke designs based on customer requirements.
Sub-sea Oil & Gas
Ceramic Seals Limited has a proven track record in supporting the subsea oil and gas industry through the design and manufacture of high-performance feedthroughs and electrical isolators. Our ceramic-to-metal assemblies are engineered to withstand ultra-high pressure environments, offering long-term reliability where access is limited and failure is not an option.
In subsea applications, both scheduled and unplanned maintenance can carry significant operational and financial costs. This makes the integrity and durability of each component absolutely critical. Our assemblies are designed for pressure-tight electrical isolation, ensuring continued performance under extreme mechanical stress and corrosive conditions.
We implement stringent quality controls at every stage of production, including helium leak testing, dimensional inspection, and electrical validation, to guarantee performance and maximise component yield. Each assembly is fully qualified prior to dispatch, delivering confidence to operators in high-risk, remote environments. Our solutions are trusted by clients across the oil and gas sector for both new system development and critical upgrades.
01 - FAQs
Are your ceramic-to-metal seals qualified for ultra-high pressure sub-sea use?
As standard, seal assemblies are not pressure-rated; however, we can perform in-house pressure testing up to 400 bar when required. For higher pressures, validation testing can be arranged through our network of approved test partners.
Do you offer corrosion-resistant materials suitable for saltwater environments?
As an alternative to our standard controlled expansion alloy (Alloy 42), we commonly offer materials such as copper-nickel alloys, Inconel (Alloy 600 or 625), or stainless steels for applications requiring enhanced corrosion resistance.
Laser & Optics
Ceramic Seals Limited specialises in the manufacture of hermetic optical assemblies for demanding laser and optics applications. We frequently integrate single-crystal sapphire lenses into ceramic-to-metal assemblies, delivering excellent optical clarity, broadband transmission, and robust environmental sealing. These components are ideal for use in high-vacuum, high-temperature, and high-energy systems where precision alignment and long-term stability are critical. Our in-house capabilities, including vacuum brazing and precision machining, ensure accurate, repeatable results tailored to specific wavelengths or system geometries. Whether for diagnostics, beam delivery, or vacuum window applications, our assemblies offer durable, high-performance solutions for optical system integration.
01 - FAQs
Do you offer anti-reflective coatings or custom optical path configurations?
Yes, specific lens profiles or optical coatings can be provided based on customer requirements. We’re happy to discuss options to suit your application.