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Rubber Seals and Mouldings in Space

With the rise of privately funded space programs from the worlds super-rich elite, seeking to boldly go where no entrepreneur has gone before, space really is the place to be. Cheaper commercial methods of launching satellites and space missions have provided NASA with a much needed boost, and with Trump and Musk strapped in, colonisation of the moon and crewed missions to Mars now appear to be firmly back on track.

Obviously we’re surrounded by thousands of satellites. In 2024 there was an estimated 9900 orbiting the Earth, this figure seems to vary from source to source but one reckons there may be as many as 60k by 2030. All of these have an abundance of seals, gaskets and mouldings.

Much more glamorous is the recent success of NASA’s Parker Solar Probe (main image) which became the first spacecraft to fly through the corona – the Sun’s upper atmosphere, facing brutal heat and radiation. The probe has four instrument suites designed to study magnetic fields, plasma and energy particles and image the solar wind. These are protected by a 113mm thick solar shield made of composite material. Even with this, the forces that seals and gaskets had to withstand are massive compared to anything found on our own planet.

The hazards of space

Wherever there is machinery, electronics, communications and equipment operating in hazardous environments there will be a requirement for custom rubber mouldings, gaskets and seals made from highly-specialised materials. None more so than in the vacuum of space where hazards can come thick and fast. From extreme high and low temperatures, radiation, atomic oxygen, ultra violet and electron particle radiations, pressure and an endless assault of micro-particles of dust travelling at speeds of up to 27km per second. These MMODs (Micro-Meteoroid and Orbital Debris) are small pieces of orbiting trash and galactic ice. The damage of these hyper-velocity particles can be devastating.

For future missions to the Moon there is a further barrier to overcome. Previously encountered by astronauts on earlier missions who’s space suits became coated with dust as they collected lunar soil. Commonly referred to as Moon dust. Lunar Regolith is a grey fluffy powder that at the microscopic scale is jagged and sticks like the proverbial to everything – including itself. Not only representing a health hazard, it is prone to hanging in the low-gravity atmosphere when kicked up by rocket motor thrust or other lunar activity, it’s fine grittiness wearing down tools, seals, joints and equipment.

astronaut on the moon
Harrison Schmitt’s spacesuit became coated with dust as he collected lunar soil samples.
Credit: NASA

Where are rubber seals, gaskets and
mouldings used in space

Rubber components can be found in the following applications used in satellites, space and launch vehicles:

  • Docking Seals
  • Fuel Feed-lines
  • Valves
  • instrumentation
  • Propulsion Systems
  • Thrusters
  • Around structural parts
  • Gyroscopes
  • Solar Panel Arrays
  • Reaction wheels on micro-satellites
  • Space Suits

Astronauts wear Prada

Well not quite yet, but Axiom and Prada have got together to modernise NASA’s trusty suit for their historic Artemis III mission in 2026, marking humankind’s first return to the moon since 1972. Creating a far more flexible, one size fits all unisex design with an operational use of up to 8 hours and the ability to include specialised tools. The current 1974 NASA suit had a ticket price of $12m so you won’t find many of them hanging in the wardrobes of even the most ardent of fashionistas, but the latest Prada/Axiom model is coming in at a fraction of that cost, so who knows – in generations to come you may find them hanging next to your skiing jacket.

Todays spacesuits are marvels of engineering, relying heavily on advanced materials as well as chemicals to keep astronauts safe and able to operate in the vacuum of space. The prime rubber material used here is Neoprene. Used in the gloves, boots and various seals around the openings of the suits. Neoprene is resistant to water, oils and chemicals and remains flexible at low temperature, ideal for space use – as indeed it is in subsea applications where similar hazards can be encountered.

What rubber materials are
best suited to space

Materials will need to possess excellent sound and shock absorption, require minimum maintenance with no need for lubrication between parts and a high-endurance threshold under extreme stresses.

  • Butyl rubber has been used in reaction wheels which are used to stabilise and manoeuvre satellites in orbit without the use of fuelled propulsion systems.
  • Specially blended EPDMs that are primarily developed for propellants.
  • FFKM for high and low temperatures combined with excellent resistance to chemicals.
  • Silicones work better at low temperatures, regular elastomers become too firm leading to leakage, they are very durable in vacuum environments.
  • Radiation can cause issues in Polymers and natural rubbers.
  • The durability of rubbers to radiation is highly dependant on the fillers that are added to the compound.

DP Seals have an excellent background in custom materials for the Aerospace industry having supplied to leading engineering teams across the world. From nitriles, neoprenes and silicones through high-performance FKM and FFKM to cutting edge polymers like silicone perfluoroelastomer and nanotech rubbers, DP Seals uses its 40-year plus experience in rubber chemistry to work with compounders to develop the right blend whatever the application.

https://dpseals.com/materials/rubber-materials-expertise/

DP Seals The Unseen Advantage

DP Seals adds value at every production stage, especially during the design phase.

We can add value in all the following areas:

  • Ultra-high pressure and vacuum sealing
  • Low outgassing
  • Expertise in FFKM
  • Chemical resistance
  • Radiation compatibility
  • Electrical insulation
  • Co-moulded and conductive rubber
  • Combined in-tool metal and rubber mouldings
  • Low friction and wear
  • Fluorination

See our Product Development page on our website.

https://dpseals.com/services/the-design-process/

The last word

Although the future of commercial space travel seems to be firmly in the grasp of the worlds super rich – it should be remembered that not so long ago, one man and his intrepid, resourceful dog managed to make that trip to the moon and back in just a day.

Beat that President Trump.

 

To discuss any requirements you may have or to find out more about DP Seals range of services get in touch.

Custom Rubber Anti-Vibration Mounts

Stylus custom rubber anti vibration dampers

Tame the Tremors: Custom Rubber Anti-Vibration Mounts for Demanding Projects

Silence the roar, tame the tremor, and extend the life of your critical equipment. As a design engineer, you understand the havoc vibration can wreak on your creations, from delicate instruments to high-performance machines. Enter the hero: custom rubber anti-vibration mounts. These unsung champions offer a powerful and adaptable solution to absorb and dampen vibrations, protecting your equipment and ensuring optimal performance across diverse industries.

Let’s delve into the world of custom rubber mounts.

 

What are anti-vibration mounts?

Custom rubber anti-vibration mounts are precisely engineered components, typically made from elastomers like Natural rubber, Fluorosilicone, Butyl and Silicone. They are designed to:

  • Reduce vibration transmission: Absorb and dissipate vibrations generated by motors, machinery, or environmental factors.
  • Protect equipment: Shield sensitive components from damaging vibrations, extending lifespan and reducing maintenance costs.
  • Improve functionality: Eliminate vibration-induced noise, chatter, and instability, ensuring precise operation and accurate results.

Industry-Specific Solutions

Custom mounts cater to unique requirements across various sectors:

  • Aerospace: Lightweight and high temperature solutions to protect sensitive electronics in satellites, launch vehicles, and aircraft from harsh vibrations.
  • Energy: Durable options for wind turbines, generators, and oil & gas platforms.
  • Food & Beverage: Food-grade mounts for delicate machinery in processing and packaging lines.
  • Instrumentation & Electronics: Maintain precise measurements and prevent damage to delicate sensors and devices.
  • Medical: Guard sensitive medical equipment and provide patient comfort in MRI machines and other diagnostic tools.
  • Motorsport: Optimise performance and protect high-performance engines and components from the rigours of the track.
  • Subsea: Withstand extreme pressures and corrosive environments while protecting underwater equipment.
  • Specialist Automotive: Tailored mounts for high-end cars, motorbikes, and off-road vehicles.

Material Considerations

Choosing the right elastomer is crucial:

  • Temperature resistance: Consider operating temperatures and potential thermal fluctuations.
  • Chemical resistance: Select materials compatible with surrounding fluids and environments.
  • Dynamic properties: Match stiffness and damping characteristics to specific vibration frequencies.
  • Load capacity: Factor in weight distribution and vibration intensity.

Types of Anti-Vibration Mounts

  • Cylindrical: Versatile, offering good vibration isolation across various frequencies.
  • Grommets: Ideal for isolating cables, pipes, and hoses.
  • Bonded Mounts: Combine rubber and metal for high strength and stability.
  • Bushings: Absorb vibrations in rotating shafts and bearings.
  • Engine mounts: Manage engine vibrations in vehicles and machinery.
  • Beam mounts: Support heavy equipment and isolate floor vibrations.

Our Manufacturing Techniques

  • Transfer Moulding: Efficient for high-volume production of complex shapes with excellent dimensional accuracy and tight tolerances.
  • Compression Moulding: Cost-effective for simpler shapes and lower volumes, providing consistent quality and good vibration isolation.

Benefits of Custom Mounts

  • Optimised performance: Tailored to your specific application, ensuring maximum vibration isolation.
  • Material selection: Choose the perfect compound for your environment and requirements.
  • Enhanced durability: Built with the right materials and techniques for longevity in demanding environments.
  • Cost-effectiveness: Avoid overpaying for generic mounts that don’t fully meet your needs.
  • Reduced maintenance: Minimised vibrations protect equipment, reducing downtime and maintenance costs.

 

Ready to conquer vibrations?

Partner with DP Seals to discuss your unique project needs and receive personalised recommendations. As a reputable manufacturer experienced in custom rubber anti-vibration mounts we’ll help you explore various material options and manufacturing techniques to keep your project running smoothly and vibration-free.

Don’t let vibration limit your designs. Embrace the power of custom rubber anti-vibration mounts and unlock the full potential of your engineering marvels!

Extreme Temperature Seals

When designing extreme temperature seals, gaskets and mouldings use these top tips based on DP Seals 40 plus years experience in the industry and feedback from our design engineer customers.

Exposure to temperature is a significant area to be aware of when making material choices.

Here are some top tips to think about when designing rubber parts.

Tip 1: Consider temperature in balance with other performance characteristics

When designing your custom rubber seal, gasket or moulding think about all types of exposure that the part will come into contact with. So whether you need low temperature flexibility or high temperature resistance, this must all be balanced with the need to resist certain fluids, for example fuels and solvents.

Tip2: Get expert advice and support

Engineers told us that they need to think about the performance characteristics of rubber material at different temperature ranges including things like out-gasing, chemical background, thermal expansion and safety in fault conditions.

This is, of course, an important area and in the following diagram you can see how certain materials compare with low and high temperature ranges.

It is clear that the right base polymer is key,  however,  through bespoke compound formulation we can pinpoint and provide the best material for your application performance. At this stage we’d recommend getting expert advice from your manufacturer. DP Seals has over 40 years experience in material technology and we can help you formulate exactly the right blend. Talk to your manufacturing partner as early as possible; good communication can save a lot of time and money in the long-run.

Tip 3:  Rubber can operate in temperature ranges you might not expect

As you can see from the previous diagram some Silicones can perform at minus 100° degrees C and even lower. Right at the other end of the scale they can withstand excursions to over 300° degrees C, depending on the grade used and compound formulation.

One of the most extreme challenges we have overcome was a requirement to have good fuel resistance and to get down to below minus 50 degrees C. After sampling and subsequent witnessed testing we managed to get a low temperature HNBR down to below this minus 50 with a good seal maintained.

Tip 4: You might need to make some trade-off

With most organic materials there is normally a trade-off for each end of the scale. For example we can compound a Nitrile rubber to remain flexible at low temperatures down to -40°C and more. We can also formulate a grade that is good at the top end of say 120°C, but we cannot always help with both requirements together, so again material base polymer choice is critical.

Summary

In this article we’ve touched on some of the key things engineers should consider in respect to temperature when manufacturing custom rubber, seals, gaskets or mouldings. We’ve outlined:

  • The importance of considering temperature in relation to other things the part could be exposed to.
  • The benefits of getting expert advice.
  • The fantastic ranges of temperature that rubber can operate in.
  • The performance characteristics of material at different temperature ranges and the need to sometimes make trade-offs.

However, temperature is just one consideration and shouldn’t be seen in isolation. Get in touch to discuss your requirements.

The Cleaning Process

The Early Days

Our cleaning department has evolved over the years and become a major part in our production process. Steve Collinson started in the cleaning department 22 years ago and recalls the early days. He had an industrial tumble dryer, two slow speed rotating tub machines and very limited sizes of ceramic media. In addition there was one N-180 cryogenic deflashing rubber machine using liquid nitrogen and aluminium oxide balls. This machine had an on/off switch and limited speed control. That was it!

Steve would load the machine, leave it for about 15 minutes and hope that everything was okay and not smashed up when he returned. Next he would shovel out the seals, gaskets or mouldings complete with the cleaning balls and very carefully separate the two.

Entering the computer age

A couple of years later a new TS10 cryogenic machine was installed which was a big investment for the company . This changed everything dramatically as it was computer controlled and enabled much more accurate control of the whole process. A vast storage tank was installed outside the building which, to this day, still gets refilled every week.

The TS10 has the ability to spin the drum at much faster speeds up to 6000 rpm. Liquid Nitrogen is sprayed into the tank until it has reached the desired operating temperature which is, on average, -75C.  This freezes the product, at which point media is blasted into the tank to remove excess flash. Once the process is complete the media is automatically separated and passed back into a storage tank. At this point the hatch can be opened and, whilst the drum rotates very slowly, the product slowly empties, saving a huge amount of time.

A flexible, modern approach

DP Seals recently added an even newer cryogenic machine and this has more than doubled the throughput of work. With the evolution of different cleaning medias we are able to clean very small, fragile parts in these two cryogenic machines.

Whilst these machines have transformed the control and speed of cleaning Steve still uses the variety of rotating tub machines to provide greater flexibility on how every product is cleaned.

Over the years the cleaning process at DP Seals has improved significantly and we’ll continue to invest to keep ahead of the game.

 

Rubber Mouldings Checklist

Examples of DP Seals custom rubber seals, gaskets and mouldings

The importance of early communication with your rubber seal manufacturer

Producing a rubber seal, gasket or moulding for your product requires significant collaboration between engineers, production teams, material technologists and the manufacturer. This rubber mouldings checklist for engineers has been designed to ensure communication is as effective and smooth as possible.

The time and cost pressures on engineers today are higher than ever. By communicating early and thoroughly with your chosen manufacturer you will have the best chance of saving time, reducing costs and gaining a competitive advantage.

On the contrary leaving your choice of material, profile and manufacturing process until too late could force you into choosing a standard product which compromises product performance. Alternatively, last minute manufacture of a specialised moulding could result in delays to market entry and higher costs overall.

For an engineer to communicate clearly it is crucial to explain the thought process behind the work, be it with your team, business or clients. We trust this handy checklist will play a part in helping you do just that.

 

Key Questions & Considerations When Producing a Rubber Seal, Gasket or Moulding

What needs sealing?

The answer to this question helps point the way towards choice of an injection, transfer or compression moulding process. Some key considerations include:

  • What is the part geometry? Consider use of videos and pictures in addition to part drawings to help explain requirements to your manufacturer.
  • What other materials will be part of the application?
  • What is the overall mechanical arrangement of the application in which the seal or moulding will operate?

Why does it need sealing?

Rubber comes in a wide variety of forms and compounds, all with different performance characteristics, and this helps to make initial material choices. Consider the following:

  • What problems are you trying to solve? Vibration, Leakage, Protection (Dust, Magnetic interference, Chemicals, Water, Solvents)
  • Is there a requirement for rubber to metal bonding or could this help strengthen the part design?

What timescale are you working to?

Understanding your project goals helps ensure you get your product to market in a timely and efficient manner. Consider the following:

  • 3D printing & rapid prototyping can help in identifying faults and allow you to try out different versions of your seal, gasket or moulding. By doing this, the development process can be sped up significantly.

What are the budget parameters?

It is important to understand your short or long term planning approach to help get the best return on your investment.

  • Choice of material may increase upfront costs but help improve product lifespan to deliver an improved ROI.
  • Is there a requirement for the re-use of moulds & tooling?
  • Volume/Quantity of parts, repeat order requirements and batch consistency into the future.

What are the expected performance characteristics of the application?

It is important to understand all the parameters that might influence your seal or moulding including:

  • Type of motion experienced by the application. Which of the following conditions will the seal work under and for how long? Static/Dynamic.
  • Displacement and flexibility in respect to rubber hardness characteristics.
  • Required Tolerances – only where required and avoiding defaulting to metallic, machined or turned parts.
  • Fluids. What fluids will the seal be exposed to in both its primary use but also when being cleaned or lubricated, for example?
  • Temperature. What temperature ranges will the seal need to work under, both hot and cold? What is the importance of temperature performance in relation to other factors?
  • Contaminants. What abrasive external contaminants might the seal be exposed to?
  • Ozone. Will there be a presence of ozone which can attack rubber?
  • Processes. Will the rubber be exposed to processes such as sterilisation by gas, autoclaving or radiation?
  • Light. Will the rubber be exposed to ultra-violet or direct sunlight?
  • Out-gassing. Will the rubber be exposed to the potential for out-gassing in vacuum applications?
  • Water. Will the seals be exposed to water?
  • Pressure. What pressures will the seal work under, both low and high?
  • Friction. What level of friction will the seal be exposed to?
  • Quality. What quality of finish is required and what are the key priorities? Will all elements of the part require the same level of quality?

We hope you found this article useful and have produced the  Engineers Checklist should you require a handy reference or want to share with colleagues. Download it for free now.

Low Temperature Seals

Subsea silicone rubber cable glands & connector seals

Seals and similar mouldings that offer reliable and effective performance at very low temperature are indispensable to a wide variety of industries – from aerospace and oceanography to oil and gas exploration and chemical processing. Manufacturing such components calls for a detailed understanding of both the materials suited to the task and the environments in which they will function.

As in most applications, choosing the right material and then formulating it in the way that best meets the operational criteria are essential prerequisites to success – and oversights or compromise at this stage will almost certainly lead to seals that become unacceptably brittle, lose compression and inevitably leak.

Working with trusted long-term partners such as Clwyd Compounders and Solvay Speciality Polymers, DP Seals is able to select from a wide range of FFKM, FKM and other advanced materials – each with a definitive set of characteristics that not only ensure predictable performance at temperatures of -40°C and below, but also provide excellent resistance to acids, alcohols, hydrocarbons and many other aggressive agents.

Outstanding performance

Where FFKM is concerned, its virtually unbreakable chemical structure, exceptional stability, low permeation and low compression set all make the material an ideal choice for low temperature applications, yet very few moulding companies are keen to promote its use because of perceived problems about production difficulties and cost.

In contrast, DP Seals has pioneered the use of innovative production techniques to address and resolve those issues – with its own in-house engineers custom-making tools to produce FFKM seals to very exacting specifications and for an increasingly diverse range of applications – and its ever expanding expertise proving that concerns related to mixing, mould characteristics and prolonged postcuring are all unfounded.

Proven expertise

In recent years, the company has worked closely with industry leaders to develop critical components for sub-sea signal, data and power connectors, and in practice, these have provided exceptionally resilient performance in environments where very low temperatures, high pressure and fluctuating chemical properties are all everyday realities.

The company has also manufactured seals for the communications antennae of Royal Navy submarines and designed FFKM seals for the National Oceanography Centre’s latest generation of miniaturised microfluidic sensors. In this latter example an endurance target of 100,000 sampling cycles was just one aspect of the highly demanding specification.

While low-temperature seals remain one of the most challenging areas of activity, the on-going research into materials and processing techniques is extending industry’s options all the time – and giving an ever increasing range of viable solutions to operating in the most hostile environments.

 

If you think we might be able to help with low temperature rubber seals for your application get in touch and we’d be happy to discuss your requirements.