Case studies & Technical articles

Challenge
Hydrogen at extremely high pressures of over 800 bar must be dynamically sealed in electrically operated tank pressure control valves (Fuel Cell Electrical Valves)

Solution
The sealing of the regulating valve or piston rod with a wide variety of requirement profiles and extreme pressure ranges (up to 800 bar) is carried out via a special spring energized U-ring solution made of application-optimized PTFE material.

Customer benefit
The design which based on the customer installation space offers valve manufacturers a universal sealing solution. This piston rod seal meets all functionality requirements such as pressure stability, chemical and temperature resistance as well as wear resistance.

The transformation in the automotive world towards electrification offers new, technical challenges. One aspect of the mobility solution of tomorrow is the generation of electricity using "green" hydrogen. "Green" hydrogen as a storable and transportable energy source is seen as part of the solution for the mobility of the future. Hydrogen handling brings with it major challenges such as high pressures, which are necessary for storage in the tank. These pressures are brought to an optimal circulatory level during energy conversion. This means that the interfaces of the valves must be absolutely tight to avoid dangerous media enrichment.

The optimized high-performance plastic based on PTFE securely seals the valve interface for this customer-specific application. The product development also ensured the requirements with regard to pressure stability, media resistance and ease of installation with minimal installation space dimensions. This resulted in a simple but sophisticated sealing solution that combines customer needs from a technical and economic point of view.

Additional high-performance sealing materials and designs for hydrogen applications are available for comparable customer-specific applications.
Please send inquiries about this product solution to: automotive[at]elringklinger.com

Challenge
High-pressure fuel piston pumps used as pressure generators up to 500 bar (petrol) and up to 2700 bar (diesel) must ensure the lowest possible leakage on both sides while separating the media (fuel/engine oil) and achieve the required engine service life.

Solution
Dynamic sealing system as double-acting, spring energized U-ring with guide ring made of high-performance compound. This sealing system offers a unique performance over the entire temperature range from -40 °C to +180 °C, dynamic range of requirements and with alternative fuels.

Customer benefit
The multifunctional sealing system offers pump manufacturers an easy-to-install and economical solution. Thanks to the special seal design, the combination of components could be optimized and the overall system costs reduced.

The automotive industry is undergoing massive change with the goal of "zero emissions". Electromobility is the focus of long-term change. With regard to fleet effects that can be realized in the short term, combustion engines are also relevant and offer potential.  

An optimized injection process can increase engine efficiency and further reduce emissions. These optimizations also have an impact on the respective high-pressure pump sealing system, the further development of which is described in this case study. The result of the material and design optimization is a pressure-resistant sealing system with the lowest possible leakage and the use of alternative fuels. This wear-resistant, high-performance sealing system sets new standards under the tougher conditions in highly dynamic piston pumps (up to approx. 5 m/s).

Our quality-oriented and economic efficiency, combined with state of the art production methods, convince our customers worldwide.
Further case studies from the Powertrain Fuel sector you will find here.

Please send inquiries about this product solution to:
automotive[at]elringklinger.com

Challenge
During wet chemical etching of silicon wafers for photovoltaics, reaction heat is generated by aggressive mixed acids, which must be dissipated in the process.

Solution
The mixed acid is pumped in a circuit through a Thermo-X™ Shell and Tube Heat Exchanger made of PVDF and cooled in counterflow via a cooling water circuit.

Customer benefit
The Thermo-X™ Heat Exchange produces a permanent cooling process that ensures etching can take place in the optimum temperature range. This guarantees a smooth production of the wafers and increases the efficiency of the production facility.

Through application-specific design, ElringKlinger determined the optimum size of heat exchanger required for the cooling process and designed it in accordance with the Pressure Equipment Directive. To ensure economic efficiency, essential components are manufactured using injection moulding. This also produces improvements in surface qualities which improved the efficiency of the plant by reducing particle contamination of the process medium. Here you can find more information about the different types of Thermo-X™ Heat Exchangers.

Please send inquiries about this product solution to:
chemical-process[at]elringklinger.com

Challenge
Our customer was looking for a coating for metallic temperature sensors to seal against an aggressive environment with lactic acid.

Solution
By choosing weldable high-performance plastics that are resistant to lactic acid and also have food approvals, it was possible to develop a tailor-made solution for the custom

Customer benefit
This ensures that the sensor is protected against its environment and its functionality remains unrestricted. The interaction of material and design prevents a contamination by germs and ensures the process quality.

High-performance plastics based on fluoropolymers are ideal for use in food technology. They have the property of being largely inert and therefore physiologically harmless. The good non-stick properties of the surfaces counteract impurities and contamination by germs and the contours are easy to clean.

In this case our customer was looking for a material that in addition to the usual food approvals according to GMP, FDA, (EU) 10/2011, (EC) 1935/2004 and (EC) 2023/2006 also complied with the 3A Sanitary standard. This is absolutely necessary to protect the sensor used from contact with lactic acid.

The plastic coating of the sensor was constructed according to the guidelines of the Hygienic Design which prescribes the avoidance of dead spaces, undercuts, sharp edges and rough surfaces.The challenge was to combine several plastic components to encase the sensor due to its inhomogeneous geometry. This was achieved through the use of weldable high-performance plastics. The product solution which has been developed together with the customer ensures the protection of the sensor in a difficult environment without compromising its sensitivity.

Please send inquiries about this product solution to:
food-pharma[at]elringklinger.com

Challenge
Production of a seal that meets all customer-specific, technical requirements on the one hand and complies with the requirements of the FDA medical device approval authorities on the other. In addition, the manufacturing process is subject to the medical standard DE EN ISO 13485. 

Solution
For use in an electric motor for surgical power tools, ElringKlinger worked with the customer to develop an ElroSeal™ high-performance rotary shaft seal with a special sealing lip and material concept for use in medical technology.

Customer benefit
With the help of the ElroSeal™ high-performance rotary shaft seal, the customer can meet quality and safety standards that are crucial for use in medical technology and its validation.

Especially in the production of medical devices and components, it is crucial to meet all relevant medical standards. The components used and their material properties must be medically safe, repeatedly sterilizable, and also medically compliant according to FDA and RoHS & REACH regulation.

With power tools and their electric motors, rotational speeds of several thousand revolutions per minute are reached, bringing the seal to its load limit.

For this application, ElringKlinger developed a sealing system that meets customer requirements for low coefficients of friction, high media and temperature resistance, and strict sterilization specifications of 1,000 cycles. This high-performance seal is characterized in particular by its durability, ensured by a correspondingly careful selection of materials.

Please send inquiries about this product solution to:
lifescience[at]elringklinger.com

Challenge
Particularly in the semiconductor sector, there are high demands on the axial pull-out forces of components that are to be connected with PTFE. In this area, the requirements for diaphragms in particular are very high. The design of the diaphragms must prevent contact between the insert and the medium.

Solution
By selecting a suitable material, it is possible to realize the required conformities to the membranes through the stamping manufacturing process.

Customer benefit
The embossing manufacturing process of diaphragms enables a higher load capacity of insert component connections and prevents contact with the medium. This has made it possible to significantly increase the axial pull-out forces of the component to be connected.

The demands placed on diaphragms are continuously increasing. As soon as they cannot withstand the mechanical and chemical stress in closed systems, contamination occurs. Such contaminations lead to failures, which are associated with enormous costs. At the same time, the components are subject to a wide variety of regulations with additional requirements. Here, the focus is mostly on the following areas:

• Food area according to (EU) 10/2011 and FDA 21 § 177.1550
• Medical area according to USP Class VI and ISO 10993-5
• Semiconductor technology (ultra-pure water, aggressive chemicals)

ElringKlinger Kunststofftechnik has succeeded in further developing membranes in such a way that they can withstand the required mechanical and chemical stresses while complying with strict regulations. 

This is achieved through a permanent bond between the PTFE layer and the associated component. By further developing this connection, it has been possible to almost double the axial pull-out forces. These essential properties allow dynamic movements of the diaphragm, which greatly increases its range of application.

Please send inquiries about this product solution to: mech-engineering[at]elringklinger.com

Challenge
Sealing of a control valve for the main cooling systems in combustion and hybrid vehicles. Provide ideal dynamic and static functionality, with minimal friction at temperature range of -40°C to +140°C and a 300,000 km lifespan.

Solution
Due to the design complexity and the requirement for low friction combined with a need for superior sealing performance, only an injection-molded Moldflon™ jacket with a supporting spring could have been considered. 

Customer benefit
The „Plug-and-Place“-sealing solution combines static and dynamic sealing functionality in one piece. By offering an one piece solution the customer was not only able to simplify the assembly concept but also reduce the risk of assembly errors or potential leakage.

The component geometry that had to be sealed and the requirements for the control valve in the main cooling system lead to different challenges: Resistance to coolant; temperature resistance -40°C to +140°C; minimum leakage; 300,000 km  lifespan; tolerance compensation of up to 0.7 mm; statically sealed without an additional elastomer seal.

Based on the geometry selected by the customer, a seal jacket made of Moldflon™ MF10010 was designed. Injection molding of Moldflon™ MF10010 enables increased design flexibility combined with cost savings due to less material waste and scrap. 

In order to guarantee sealing functionality over the applications lifespan, the seal required additional force from a spring which reliably seals the static and dynamic sides of the seal with relatively constant force against the sealing surfaces.

The original idea for the described solution was based on ElringKlinger’s spring-energized  seals. In order to be able to transfer this concept to the valve application, the impact of the spring force had to be adjusted accordingly to the specific conditions of the installation space. 

A specific spring assembly process has been developed in order to guarantee full sealing functionality. This ensured the customer would have full sealing functionality with constant valve adjustment forces, even for critical tolerances.

The new sealing concept reduced the number of components and therefore lowered the risks of assembly errors and leakages. These improvements and the economic/environmental advantage of the "plug and place"-sealing solution ensured an entirely satisfied customer.

Please send inquiries about this product solution to:
automotive[at]elringklinger.com

Challenge
The primary challenge was to manufacture a component for capacitive level measurement in compliance with the requirements applicable in the food industry, such as GMP, FDA, (EU) 10/2011, (EC) 1935/2004 and (EC) 2023/2006. Compliance with the listed regulations was a fundamental requirement for all materials and components used.

Solution
Joint development with the customer and implementation of all required standards or specifications by ElringKlinger Kunststofftechnik GmbH. 

Customer benefit
After joint development, we were able to provide the customer with a final assembled assembly with appropriate packaging according to required standards. All components are manufactured or processed in-house or procured via approved and certified suppliers.

Continuous process monitoring is essential in food production, as well as in process engineering, in order to meet the high quality and safety requirements. PTFE is a frequently used material for these applications, which is characterized by its excellent food compatibility and anti-adhesive properties, while at the same time being highly resistant to aggressive media.

With our many years of experience as a supplier to the food industry in the field of sensor technology, we supported our customer in the development and manufacture of a capacitive level sensor for the food-contact area. In the course of the close cooperation, the customer's product portfolio could be extended or supplemented by the application area of level measurement. 

In order to be able to offer the customer further added value in his supply chain, various other components are procured, assembled and installed in an assembly in addition to the production of the plastic components. Final assembly is carried out at our GMP-certified sites and complies with the regulations already listed. 

For decades we have been supplying our customers with components such as casing, shrink-wrapped, coated and welded components for applications in sensor technology. 

We would also be happy to support you in the development and expansion of your product portfolio.

Please send inquiries about this product solution to:
mech-engineering[at]elringklinger.com

Challenge
Modern aircraft have highly complex adjustment mechanisms that are crucial for the safe flight and landing characteristics of the aircraft. The protection of these safety-critical actuator units of "flap" and "slat" is subject to high requirements. This requires innovative and reliable sealing systems to protect the mechanisms from external media ingress such as water, ice and dirt.

Solution
To protect the actuators, ElringKlinger further developed the existing sealing concept of PTFE sealing lip and anodized aluminum housing into an injection-molded ElroSeal™ radial shaft seal.

Customer benefit
The result of further development is the "injection-molded rotary shaft seal". This innovative seal consists of a glass-fiber-reinforced injection-molded housing and a PTFE compound sealing lip. The reinforced plastic housing reduces the component weight by 40% and enables faster and more flexible production than the existing seal concept. 

Adjusting wing geometries are well established in aviation and are essential for today's state-of-the-art machines. This safety-critical area must be protected from external media ingress from the environment in order to provide you with maximum safety and reliability in the air.

Last year, we were able to demonstrate our know-how within a project for one of our customers in the field of passenger air transport. The aim was to further develop our existing sealing concept of a high-performance PTFE sealing lip and an anodized aluminum housing for the actuators for "Slat" wing adjustment. 

To meet this requirement, various solution concepts with different housing materials were investigated. The challenge of media resistance to anti-wear greases, as well as the wide temperature application range of -54°C to +90°C, were technically solved in addition to a number of other conditions.

The result of this further development is the "injection-molded rotary shaft seal". This ElroSeal™ sealing ring consists of a high-performance PTFE compound as the sealing lip and a media-resistant glass-fiber-reinforced plastic, which is injection-molded around the sealing lip. The glass-fiber-reinforced plastic housing allows the overall weight to be reduced by 40% compared with the existing seal concept with aluminum housing. The high sealing performance is retained. In addition, the new design enables faster production times and agile availability with high reproducibility.

Please send inquiries about this product solution to:
aerospace[at]elringklinger.com

Challenge
Increasing rotation speed combined with minimum power dissipation and maximization of running performance are the focus of current developments in e-machines/e-drives.

Solution
ElringKlinger Kunststofftechnik has developed a new product family that meets these more stringent requirements and offers customers even greater scope to meet future challenges.

Customer benefit
Through the implementation of an innovative design and the use of innovative materials and manufacturing processes, the customer can realize up to 50% higher circumferential speeds, with continued low power loss. The efficiency of e-axles can thus be further increased and the running performance extended.

With the transformation of the automotive industry in the field of drive technology, experience, progress and requirements in the area of electric axles are steadily increasing. 

In response, ElringKlinger Kunststofftechnik was asked to what extent it could offer a high-performance seal for electric drive axles that would exceed standard market requirements by up to 50% in terms of rotational speed and overall mileage. 

Close collaboration between product, material and process specialists resulted in the development of a new generation of PTFE-based rotary shaft seals. This new higher performance product family is now available under the name "ElroSeal™". 

This further development has ensured that new customer requirements are met and the performance of the application interface has been significantly increased.

Further information about the ElroSeal™ can be found here.

Please send inquiries about this product solution to:
automotive[at]elringklinger.com

Challenge
The backup ring of a sealing system for screw compressors failed after a very short time. The failure led to a massive oil leakage at the compressor. The cause was a provoked failure of the primary seal and a non-functioning oil return system. Thereby the system pressure built up on the backup seal, for which, however, it is not designed.

Solution
ElringKlinger quickly identified the problem and provided the backup seal with a supporting extension so that safe operation is maintained even in the event of a defect in the primary seal under unchanged application conditions.

Customer benefit
The improved secondary seal has proven its worth in numerous test bench runs and is being successfully mass-produced by ElringKlinger worldwide.

The requirements for modules and assemblies in screw compressors are constantly increasing. What the individual components must achieve is increasingly influenced by the ambient conditions. Ever higher performance requirements and improper handling additionally increase the risk of failure.

A manufacturer approached ElringKlinger with a problem in the area of shaft sealing in order to obtain a sustainably efficient solution. The actual causes though were only uncovered by internal test bench trials.

The challenge was to design a sealing system consisting of two rotary shaft seals in such a way that, in the event of a failure of the primary seal as well as a simultaneous failure of the oil return system, the backup ring would continue to seal despite the maximum pressure load. Following a detailed description and clarification of the requirements, ElringKlinger was able to design an appropriate solution.

The system was ultimately fitted with rotary shaft seals which, thanks to specially adapted material properties, permit long service lives even with dry running/lack of lubrication. Furthermore, the backup ring was optimized into a high-pressure special type.

Please send inquiries about this product solution to:
mech-engineering[at]elringklinger.com