Vacuum rotary feedthroughs
Vacuum rotary feedthroughs: High-precision industrial solutions
Technical data
Protection class
IP51 (higher on request)
Rotational speed
0-300 rpm
Housing material
Aluminium, Stainless steel
Number of implementations
1-24
Additional services
Combination of different feedthroughs
Media implementation specification
- Number of pneumatic/liquid feed-throughs: 1 – 24
- Connection sizes: M5, 1/8″, ¼”, 3/8″, ½”, 5/8″, 1″, 1¼”
- Straight or angled connections
- Pressure: up to 1300bar, 130MPa; 20000 psi, vacuum 0.01torr, 30HG
- Media: Compressed air, Vacuum, Hydraulic oil, Return oil, Water, Hydrogen, nitrogen, vapour, cooling water, coolant, hot water, acids, bases and much more
Product overview
All details about our slip rings can be found in our product overview
Single and multi-channel rotary feedthroughs for vacuum
Vacuum rotary feedthroughs are specially developed to enable the transfer of gases and liquids under vacuum conditions between stationary and rotating components. Unlike conventional Rotating unions, used for hydraulics or pneumatics, vacuum rotary feedthroughs must ensure particularly tight, reliable and leak-free connections in order to maintain the vacuum. This technology is essential in industries that rely on precise and clean conditions.
Vacuum rotary transmission to rotating machine groups poses a particular challenge for sealing and design. This is because the media feed-through of a vacuum lacks the cooling effect that other media have and which normally protects sealing elements from overheating and thus from wear. When designing your customised vacuum rotary feedthroughs, we therefore ensure that the sealing preload and pressure ratios are particularly easy to match. But where exactly are such rotary feedthroughs actually used?
Areas of application for vacuum rotary feedthroughs
The transfer of a vacuum as a medium is necessary, for example, for rotary discs with several clamping stations and grinding discs for optical devices.
Accordingly, vacuum rotary feedthroughs are used in numerous branches of industry, including:
- Semiconductor industry: Extremely clean and controlled environments are required in the manufacture of semiconductors. Vacuum rotary feedthroughs enable the transfer of gases and liquids in rotating coating and etching systems.
- Food processing: In the food industry, vacuum rotary feedthroughs are used in filling and packaging machines to minimise contact with air and extend the shelf life of products.
- Medical technology: Vacuum technology is used in the production of medical devices and pharmaceuticals to ensure sterile conditions and handle sensitive materials.
- Research and development: Vacuum rotary feedthroughs are indispensable in many research applications, especially in materials science and chemistry, where they are used in rotating reactors and analysers.
- Coating technology: In the coating industry, they are used in vacuum coating systems to apply thin layers to surfaces, which is crucial in the optics and electronics industries.
Rotary union
Choice of different housing materials
Various connection sizes for media feed-throughs
Mounting and bolt circle rotor
Optional rotary feedthrough with hollow shaft
What exactly is a vacuum?
What is vacuum technology?
Vacuum technology includes applications in which the pressure is below atmospheric pressure to enable special processes. A vacuum is created by removing gases from a closed space.
This technology is used in many industrial and scientific fields as it offers unique advantages:
- Cleanliness: Vacuum environments are free from contamination, which is crucial in the semiconductor and food industries.
- Controlled environment: Processes can be carried out under specific and stable pressure conditions, which is important for the manufacture of high-quality products.
- Efficiency: Many chemical and physical processes run more efficiently under vacuum conditions.
A vacuum is created by removing gases from an enclosed space, thereby reducing the pressure in this space to below atmospheric pressure. This can be achieved by various methods, including mechanical pumps, diffusion pumps or cryogenic pumps. The vacuum generation process typically involves several stages to get from a rough vacuum to a high or ultra-high vacuum.
Vacuum generation methods
- Mechanical pumps:
- These pumps, such as rotary vane or piston pumps, remove most of the air molecules and create a rough vacuum. They are often the first step in vacuum generation.
- Diffusion pumps:
- These pumps use a heating mechanism to vaporise an oil, which then hits air molecules and draws them out of the system. Diffusion pumps can generate a higher vacuum than mechanical pumps.
- Turbomolecular pumps:
- These pumps use rotating vanes to remove air molecules from the system and can generate a high vacuum.
- Cryogenic pumps:
- These pumps cool surfaces to extremely low temperatures, causing gases to condense and adhere to these surfaces. Cryogenic pumps are able to generate an ultra-high vacuum.
Importance of vacuum in industrial applications
A vacuum is crucial for many industrial applications, for several reasons:
- Avoidance of contamination:
- In the semiconductor industry and medical technology, extremely clean environments are required to ensure the production of components and devices without contamination. A vacuum minimises the presence of particles and molecules that could affect production.
- Controlled reaction conditions:
- In chemistry and materials science, a vacuum enables reactions to be carried out under controlled conditions. This can increase the reaction speed and prevent unwanted side reactions.
- Increased efficiency:
- Many physical and chemical processes run more efficiently under vacuum conditions. For example, coatings can be applied thinner and more evenly under vacuum, which is crucial in the optics and electronics industry.
- Improved heat transfer:
- In applications such as vacuum insulation, a vacuum is used to prevent heat transfer by convection. This leads to better insulation performance.
- Sterilisation and shelf life:
- A vacuum is used in food processing and packaging to protect products from microorganisms and extend their shelf life. Removing air from packaging prevents the growth of bacteria and mould.
- Safety aspects:
- A vacuum can also offer safety benefits, especially when handling hazardous materials. By removing oxygen, the risk of fires and explosions is reduced.
Functionality of vacuum rotary feedthroughs
Vacuum rotary feedthroughs consist of a stationary and a rotating component. The stationary component is connected to the vacuum source, while the rotating component is connected to the rotating part of the machine. High-quality seals prevent the ingress of air and the escape of gases or liquids. The precise design and the use of robust materials ensure the reliability and durability of the rotating unions, even under extreme conditions.
Advantages of vacuum rotary feedthroughs
- Highly leak-proof: They provide a reliable seal that maintains negative pressure and prevents leaks.
- Durability: Robust materials and precise construction ensure a long service life and reliable operation.
- Versatility: Suitable for various industrial applications where vacuum conditions are required.
Special requirements and solutions
The requirements for vacuum rotary feedthroughs are high. They must be made of materials that remain stable under vacuum conditions and do not release any gases. High-quality seals are crucial to ensure the integrity of the vacuum. In addition, they must be designed for operation at extremely low pressures and often high speeds.
Vacuum rotary feedthroughs are characterised by several decisive factors that distinguish them from other types of rotary transmitters:
- Tightness and freedom from leakage:
- Vacuum rotary feedthroughs must ensure particularly tight connections in order to maintain the vacuum. High-quality seals are essential here to prevent the ingress of air and the escape of gases or liquids.
- Materials and construction:
- The materials from which vacuum rotary feedthroughs are made must remain stable under vacuum conditions and must not release any gases. Robust and durable materials as well as precise construction techniques are required to fulfil the special requirements.
- Temperature and pressure conditions:
- Vacuum rotary feedthroughs must be able to work under extremely low pressures and often at high speeds. As vacuum transmission lacks the cooling effect that other media have, the seals must be particularly resistant to overheating and wear.
- Versatility and adaptability:
- They must be suitable for a variety of applications in which different media – such as vacuum, gases, liquids or electrical signals – are transmitted. Multi-channel rotary feedthroughs offer the advantage that they can transmit several media simultaneously, which is particularly useful in complex industrial processes.
- Cleanliness and contamination:
- In sectors such as the semiconductor industry or medical technology, where extremely clean and controlled environments are required, avoiding contamination through leaks or material vapours is particularly important. Vacuum rotary feedthroughs must therefore fulfil the highest standards of cleanliness.
Differences to other types of rotary transmitters:
- Electrical slip rings:
- Electrical slip rings are primarily designed for the transmission of power and signals and do not require seals that are suitable for maintaining a vacuum. They are therefore less complex in terms of sealing.
- Hydraulic rotary feedthroughs:
- These are designed to transfer hydraulic fluids under pressure between stationary and rotating parts. The requirements for the seals are different, as hydraulic fluids generally have a cooling effect and the system is not designed for vacuum conditions.
- Pneumatic rotary feedthroughs:
- These rotary unions transmit compressed air and also require a reliable seal, but not under the extreme conditions of a vacuum. The seals must be able to withstand air pressure, but the requirements for tightness and freedom from leakage are less stringent than for vacuum rotary feedthroughs.
To summarise, vacuum rotary unions differ from other rotary transmitters in their specific requirements for tightness, materials, temperature and pressure resistance as well as their ability to operate in extremely clean environments. These characteristics make them indispensable for industries that rely on precise and clean conditions.
Multi-channel rotary feedthroughs for vacuum
Multi-channel rotary feedthroughs enable the simultaneous transmission of different media – such as vacuum, gases, liquids or electrical signals – between stationary and rotating systems. This is particularly useful when complex processes run in parallel or different media are required at the same time.
Examples from the industry:
- Semiconductor industry: Multi-channel rotary feedthroughs enable the simultaneous transfer of vacuum and process gases in rotating coating systems. This is crucial for the manufacture of high-quality semiconductor products.
- Food processing: They enable the simultaneous transfer of vacuum and liquid media in filling and packaging machines, which improves product quality and shelf life.
- Medical technology: In the production of medical devices, multi-channel rotary feedthroughs are used to transfer vacuum and sterile gases or liquids simultaneously, which ensures the purity and safety of the products.
- Research and development: In materials science and chemistry, they enable the simultaneous handling of vacuum and various reagents in rotating reactors and analysers.
- Coating technology: In vacuum coating systems, they enable the transmission of vacuum, process gases and electrical signals to control and monitor the coating process.
Your customised solution
The path to a vacuum rotary feedthrough that is perfectly customised to your needs begins with a detailed consultation. We analyse your specific requirements, including the media to be transferred, the pressure and temperature conditions and the spatial conditions. This detailed information forms the basis for developing a solution that is precisely tailored to your requirements.
Our experts will support you from the initial analysis to the final installation and maintenance of your vacuum rotary feedthrough. In this way, we ensure that your systems work efficiently and reliably and last a long time.
It all depends on the seal
Our main concern when developing our technology and providing individual advice is to ensure a high level of operational readiness while simplifying installation, minimising maintenance requirements and at the same time ensuring a long service life. Achieving these goals is much more challenging for pneumatic rotary feedthroughs with standard or combined electrical media transmissions than for purely electrical slip rings or simple rotary feedthroughs. This is due in particular to the challenges associated with sealing and wear caused by friction.
The precise separation of the various media channelsand the wear on the seals pose the greatest design challenges. The rotation between the inner and outer housing leads to continuous friction, which is less of a problem with purely electronic slip rings. However, in applications where absolute tightness is required, the wear of rubber rings on plastic or aluminium is a limiting factor for the service life of the component. At rotarX, we have already successfully overcome these and other challenges for various industries.
The secret of our success lies in the use of balanced mechanical seals. In pneumatic or hydraulic rotary feedthroughs, for example, these ensure that only the actuating and restoring forces act on the seals rather than the full operating pressure, which leads to a significant increase in service life. In addition, we offer various seal ring materials such as ceramic, graphite or silicon carbide on request in order to be able to optimally meet the specific requirements of our customers. This helps to reduce maintenance costs and minimise friction on the seals.
Why RotarX?
RotarX stands for first-class quality and customised solutions in the field of rotating unions. Our extensive experience and our flexible modular system enable us to offer over 50,000 different configuration options. This enables us to deliver the optimum solution for every application, whether simple or complex.
Our strengths include:
- Durability: By using high-quality materials and innovative sealing technologies, we increase the service life of our rotating unions.
- Reliability: Our products are designed for use in demanding conditions and offer maximum reliability.
- Ease of maintenance: We design our rotating unions to be easy to maintain, minimising downtime and maximising the efficiency of your processes.
With RotarX, you can rely on a partner who understands your specific requirements and offers customised solutions that make your processes more secure and efficient.
Practical slip ring solutions for your application
Product catalogue for all slip rings
Find out about the different slip rings in our current overview. Transmission technology for complex industrial and safety-relevant applications form the core of our product range. All products can be individually adapted to the applications in order to offer you added value. Premium engineering - that is our claim for every single product we manufacture. We would like to convince you of this.
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