Metal C-Rings: Solving Submarine Repeater Sealing Challenges
Created on 07.26
Metal C-Rings: Solving Submarine Repeater Sealing Challenges
Introduction: The Critical Role of Submarine Optical Communication Repeaters
The modern world depends on high-speed data transmission across oceans, and submarine cables form the backbone of this global connectivity. These cables rely on advanced optical communication technologies to transmit vast amounts of data between continents with minimal latency. Submarine repeaters are essential components within these networks, as they amplify optical signals to compensate for attenuation over long distances. These repeaters must operate reliably for decades at depths reaching thousands of meters, where environmental conditions are extremely harsh. The integrity of the repeater housing seal is therefore paramount, as any breach can lead to catastrophic failure of the entire cable system. This is where advanced metal sealing solutions, specifically metal C-rings, become indispensable for ensuring long-term performance.
Fiber optic communication has revolutionized international telecommunications, enabling everything from streaming services to global financial transactions. The rapid expansion of 5G networks and intercontinental data centers has further accelerated the demand for higher bandwidth and more reliable submarine cable routes. Within each submarine repeater, sensitive electronic and optical components must be hermetically isolated from the surrounding marine environment while maintaining impeccable signal integrity. The sealing interface between the repeater housing and its electrical or optical feedthroughs represents one of the most critical engineering challenges in underwater fiber optic transmission systems. A single seal failure can result in multimillion-dollar repair operations, significant service disruptions, and reputational damage for network operators. Understanding the specific sealing challenges and the proven solutions offered by metal C-rings is essential for engineers, procurement professionals, and decision-makers in the submarine cable industry.
Core Problem: Sealing Challenges in the Deep-Sea Environment
The deep-sea environment presents a uniquely aggressive combination of physical and chemical stresses that push conventional sealing technologies to their limits. Hydrostatic pressure at depths exceeding 3,000 meters can reach 30 MPa or more, which compresses seal surfaces and can force leaks through microscopic gaps. Seawater is highly corrosive due to its chloride content, and it attacks seal materials relentlessly over years of continuous immersion. Temperature fluctuations caused by ocean currents, seasonal changes, and equipment self-heating create thermal cycling that causes differential expansion between metal housings and seal components. Any leakage pathway, no matter how small, allows seawater intrusion that can short-circuit electronics, corrode connectors, and degrade the optical path within the repeater. The combination of these factors makes submarine optical communication repeater sealing one of the most demanding applications in the sealing industry.
Traditional elastomeric O-rings, while effective in many industrial applications, struggle to meet the long-term reliability requirements of submarine fiber optic transmission systems. These polymer seals are susceptible to compression set, which causes them to lose their sealing force over time under constant compression. They also degrade through hydrolysis and chemical attack from seawater, leading to embrittlement, cracking, and eventual leakage. At the extreme pressures found in deep-sea environments, elastomeric O-rings are prone to extrusion into the seal clearance gap, which accelerates wear and failure. Thermal cycling further compounds these issues by creating intermittent leakage paths as the seal material expands and contracts at different rates than the metal housing. These fundamental limitations have driven the submarine cable industry to seek more robust sealing solutions, particularly advanced metal-to-metal sealing technologies.
Beyond the immediate physical stresses, the operational requirements of submarine repeaters impose additional constraints on sealing solutions. Repeaters are expected to function without maintenance for 25 years or more, as retrieval from the ocean floor is prohibitively expensive and disruptive. The sealing system must also accommodate manufacturing tolerances, installation stresses, and potential minor housing deformations over the service life. Furthermore, the seal must perform reliably across the full range of operating temperatures, from cold ocean water at the seabed to elevated temperatures during high-power signal transmission. Any degradation in seal performance can introduce moisture into the optical path, leading to signal attenuation and eventual system failure. These demanding requirements have made high-performance metal C-rings and spring-energized C-rings the preferred choice for critical submarine optical communication applications.
Solution Overview: Metal C-Rings and Spring-Energized C-Rings
Metal C-rings are precision-engineered sealing components manufactured from high-strength alloys, designed to create a reliable metal-to-metal seal under extreme conditions. The distinctive C-shaped cross-section provides inherent spring-like behavior, allowing the seal to deflect under load while maintaining consistent contact pressure against the mating surfaces. When compressed during installation, the C-ring generates a high localized stress at the sealing interface, which plastically deforms the contact surfaces to create a leak-tight barrier. This design is particularly effective in high-pressure environments because the internal pressure actually enhances the sealing force by acting on the inner surface of the C-ring. For submarine repeater housings and feedthroughs, metal C-rings offer a proven combination of strength, corrosion resistance, and long-term stability that elastomeric seals cannot match.
Spring-energized metal C-rings represent an advanced evolution of the basic C-ring design, incorporating an internal spring element that provides additional sealing force and resilience. The spring, typically made from a high-performance alloy such as Inconel X-750 or Elgiloy, is encased within the C-ring profile and exerts continuous outward pressure on the sealing lips. This design ensures that the seal maintains intimate contact with the mating surfaces even when thermal cycling causes differential expansion or contraction between components. The spring-energized configuration also compensates for minor surface irregularities, housing misalignment, and long-term relaxation of the parent material. For the most demanding submarine repeater sealing applications, Raido Sealing Products (Wuxi) Co., Ltd offers tailored spring-energized metal C-ring solutions that meet the rigorous performance requirements of deep-sea optical communication systems.
The material selection for these metal seals is critical to their success in submarine environments. Alloys such as Inconel 718 and 316L stainless steel provide excellent corrosion resistance in seawater, with Inconel 718 offering superior strength and resistance to stress corrosion cracking at elevated temperatures. These materials also exhibit minimal compression set, meaning they retain their sealing force over decades of continuous service. Raido's advanced manufacturing processes, including precision machining, heat treatment, and surface finishing, ensure that each seal meets tight dimensional tolerances and surface roughness specifications. The company's investment in state-of-the-art production equipment and rigorous quality control protocols guarantees consistent seal performance across every batch. This manufacturing excellence, combined with proven material science, makes metal C-rings from Raido a trusted choice for submarine cable operators worldwide.
Product Features and Benefits for Submarine Repeater Sealing
The high-pressure resistance of metal C-rings, with capabilities exceeding 100 MPa, makes them ideal for the most demanding deep-sea repeater applications. This pressure rating far exceeds the hydrostatic pressures found even in the deepest ocean trenches, providing a substantial safety margin for mission-critical optical communication infrastructure. The minimal compression set of these metal seals ensures that the sealing force remains stable over decades, unlike elastomeric seals that gradually lose their preload. This long-term stability translates directly into extended service life for submarine repeaters, reducing the need for costly mid-life repairs or premature cable replacement. The spring-energized variant is particularly valuable in applications where thermal cycling is severe, as the internal spring maintains consistent sealing pressure across temperature swings from 0°C to over 100°C. These performance characteristics make metal C-rings the preferred sealing solution for next-generation submarine fiber optic transmission systems.
Corrosion resistance is another critical advantage offered by metal C-rings in submarine environments, where seawater is constantly attacking exposed surfaces. The use of nickel-based superalloys like Inconel 718 provides outstanding resistance to pitting, crevice corrosion, and stress corrosion cracking in chloride-rich seawater. This corrosion resistance eliminates the degradation mechanisms that plague elastomeric seals, ensuring that the seal's geometry and surface finish remain intact throughout the service life. The metal-to-metal sealing interface also prevents the diffusion of moisture through the seal body itself, a failure mode that can occur with polymer-based seals over extended periods. For feedthroughs and cable joints, where the seal must also accommodate electrical insulation requirements, Raido's metal C-rings can be combined with ceramic or glass-to-metal sealing technologies. This comprehensive approach to sealing ensures that every potential leakage path in a submarine repeater is effectively blocked, safeguarding the integrity of the optical communication system.
The low leakage rates achieved by spring-energized metal C-rings represent a fundamental requirement for reliable long-term optical communication performance. Helium leak testing routinely demonstrates leakage rates below 1 × 10⁻⁹ mbar·L/s for properly designed and installed metal C-ring seals. This level of hermeticity prevents not only liquid water ingress but also the diffusion of water vapor, which can condense on optical surfaces and cause signal degradation. The spring-energized design provides an additional layer of reliability by ensuring that the seal remains energized even if the housing experiences minor deformation due to pressure or temperature changes. For system operators, this translates into higher mean time between failures (MTBF) for submarine repeaters, reduced maintenance costs, and improved overall network availability. These benefits are driving increased adoption of metal C-rings in new submarine cable projects globally.
Comparison with Traditional Seals: Metal C-Rings vs. Elastomeric O-Rings
Elastomeric O-rings have been the standard sealing solution in many industries for decades, but their limitations in deep-sea submarine repeater applications are becoming increasingly apparent. The primary failure modes of elastomeric O-rings in this environment include compression set, extrusion, explosive decompression, and chemical degradation. Compression set occurs when the polymer material permanently deforms under constant compression, gradually reducing the sealing force until leakage occurs. Extrusion happens when high hydrostatic pressure forces the soft elastomer into the clearance gap between the housing and the mating flange, causing mechanical damage and eventual seal failure. These failure mechanisms are not just theoretical concerns but have been documented in numerous field failures of submarine optical communication equipment. The financial impact of such failures, including cable retrieval and repair costs that can reach tens of millions of dollars, makes the selection of reliable sealing technology a top priority for network operators.
Metal C-rings overcome each of these limitations through fundamentally different sealing principles and material properties. The metal-to-metal contact eliminates the risk of extrusion because the seal material has comparable hardness and strength to the housing components. The absence of polymer materials means there is no susceptibility to chemical attack from seawater, no hydrolysis, and no degradation from UV radiation or ozone exposure. The inherent spring characteristics of the C-ring geometry, enhanced by the spring-energized design in advanced variants, provide consistent sealing force over decades without the relaxation that plagues elastomeric seals. While the initial cost of metal C-rings is higher than that of elastomeric O-rings, the total cost of ownership is significantly lower when factoring in extended service life, reduced maintenance, and elimination of failure-related repair costs. For critical infrastructure like submarine fiber optic communication systems, the reliability advantages of metal C-rings far outweigh their higher upfront investment.
Temperature resistance is another area where metal C-rings dramatically outperform elastomeric alternatives in submarine repeater applications. Elastomeric O-rings have a limited temperature range, typically between -40°C and 120°C for common materials like nitrile or fluorocarbon rubber, with significant degradation occurring at the extremes. Metal C-rings, by contrast, can operate from cryogenic temperatures to over 500°C depending on the alloy selected, providing ample margin for the thermal conditions encountered in submarine cables. This wide temperature range is particularly important for optical communication repeaters that may experience self-heating during high-power operation while being surrounded by near-freezing seawater. The thermal expansion coefficient of metal C-rings can also be closely matched to that of the housing material, minimizing differential stress during thermal cycling. This compatibility reduces the risk of seal leakage during temperature transients, a common failure mode for elastomeric seals in thermally cyclic environments.
Application Cases: Subsea Optical Repeaters, Cable Joints, and Pressure Vessels
Subsea optical repeaters represent the most demanding application for metal C-rings in fiber optic communication systems, as they must maintain hermetic sealing for 25 years or more at extreme depths. These repeaters house sensitive optical amplifiers, pump lasers, and monitoring electronics that must be protected from seawater intrusion at all costs. Raido's metal C-rings have been successfully deployed in multiple submarine cable projects, providing reliable sealing for repeater housings, optical feedthroughs, and pressure-tolerant electronics enclosures. The seals are typically installed in precision-machined grooves on the repeater housing flanges, with controlled compression achieved through bolted connections with specified torque values. The high reliability of these metal seals has contributed to the exceptional performance record of modern submarine cable systems, which achieve availability rates exceeding 99.999%. For system designers, the proven track record of metal C-rings in these applications provides confidence in specifying them for new cable projects.
Cable joints, which connect individual cable segments during installation or repair, present another critical application for metal sealing technology in submarine optical communication networks. These joints must withstand the same hydrostatic pressures as the rest of the cable system while accommodating the electrical and optical connections between cable segments. The sealing requirements for cable joints are particularly challenging because the joint housing must be assembled in the field, often under time constraints and challenging weather conditions on a cable-laying ship. Metal C-rings are well-suited for this application because they can tolerate minor misalignment and surface imperfections that are inevitable in field assembly conditions. The spring-energized variant is especially valuable for cable joints, as the internal spring provides consistent sealing force regardless of variations in bolting torque or thermal conditions.spring-energized metal C-rings have been designed specifically to meet the demanding field installation requirements of submarine cable joint applications.
Pressure vessels used in submarine optical communication systems, including branching units and power feed equipment, also benefit from metal C-ring sealing technology. These vessels must protect sensitive components while accommodating electrical feedthroughs, optical fiber pass-throughs, and sometimes chemical or hydraulic connections. The sealing interfaces in these vessels are often geometrically complex, with multiple seal surfaces that must all achieve hermetic closure. Metal C-rings can be manufactured in non-circular shapes, including rectangular and oval profiles, to match the specific geometry of each pressure vessel interface. This design flexibility allows system engineers to optimize the overall system architecture without being constrained by seal geometry limitations. Raido's engineering team works closely with submarine cable manufacturers to develop custom metal C-ring solutions for unique pressure vessel sealing challenges. The company'smetal C-ring product line offers a wide range of standard and custom configurations to meet the diverse needs of the submarine fiber optic transmission system industry.
Installation and Design Considerations for Metal C-Rings
Proper groove design is essential for achieving optimal performance from metal C-rings in submarine repeater sealing applications. The groove depth, width, and corner radii must be precisely controlled to ensure the correct amount of seal compression and to prevent damage during installation. The groove volume must accommodate the displaced seal material under compression while maintaining sufficient clearance for assembly. Surface finish of the groove and mating flange faces is also critical, with typical requirements of 0.4 μm Ra or better to ensure intimate metal-to-metal contact for effective sealing. Raido provides detailed groove design guidelines for each seal configuration, taking into account the specific material properties, operating pressure, and temperature range of the application. Engineers designing submarine optical communication equipment can consult Raido'sTechnical Center for comprehensive design support and recommendations.
Preload requirements for metal C-rings must be carefully calculated to achieve the necessary sealing stress without exceeding the yield strength of the housing components. The preload is typically applied through bolted flanges with controlled torque, and the bolt spacing and size must be designed to provide uniform compression around the entire seal circumference. Finite element analysis is often employed to optimize the flange and bolt design, ensuring that the seal compression remains within the specified range under all operating conditions. For spring-energized metal C-rings, the preload requirements are somewhat lower than for standard C-rings, as the internal spring provides a portion of the sealing force. This can allow for lighter flange designs with fewer or smaller bolts, potentially reducing the overall weight and cost of the repeater housing. Raido's application engineers can provide preload calculations and installation specifications tailored to each customer's specific submarine fiber optic communication repeater design.
Installation procedures for metal C-rings require careful attention to cleanliness, alignment, and bolting sequence to achieve reliable sealing performance. The seal and mating surfaces must be thoroughly cleaned and free of debris, burrs, or contamination before assembly, as any foreign material can create a leakage path. The seal should be positioned concentrically within the groove, and the flanges should be brought together evenly to avoid cocking or damaging the seal. Bolts should be tightened in a cross-pattern sequence to the specified torque values, typically in multiple increments to ensure uniform compression. Raido offers detailed installation instructions for each seal product and provides technical support to customers during the initial qualification and production phases. These rigorous installation practices, combined with the inherent reliability of metal C-rings, ensure that submarine repeaters achieve the hermetic sealing required for decades of uninterrupted optical communication service.
Market Outlook: Growing Demand for Submarine Cable Sealing Solutions
The global submarine cable market is experiencing unprecedented growth, driven by the insatiable demand for bandwidth from cloud computing, streaming services, and international data exchange. New cable systems are being planned and deployed across all major ocean routes, with total investment in submarine telecommunications infrastructure projected to exceed $10 billion annually by 2027. This expansion is directly fueling demand for reliable sealing components, particularly metal C-rings and spring-energized seals that can ensure long-term repeater reliability. The trend toward higher-capacity fiber optic transmission systems, with data rates exceeding 100 Tbps per fiber pair, requires repeater designs with tighter performance margins and higher reliability targets. These system-level requirements cascade down to component specifications, driving adoption of proven sealing technologies like Raido's metal C-rings. The market outlook for submarine cable sealing solutions is therefore strongly positive, with sustained growth expected for the foreseeable future.
Technological advancements in optical communication are also creating new sealing challenges that metal C-ring technology is well-positioned to address. The development of space-division multiplexing and multicore fiber technologies promises to multiply data capacity, but also requires more complex repeater architectures with additional feedthroughs and sealing interfaces. Higher power densities in next-generation repeaters generate more heat, increasing the thermal cycling stress on sealing components. Some emerging submarine cable designs incorporate free space optics for certain internal signal routing applications, adding further complexity to the sealing requirements. Metal C-rings, with their proven ability to handle high temperatures, thermal cycling, and complex geometric configurations, are ideally suited for these advanced repeater designs. Raido continues to invest in research and development to ensure that itsproduct portfolio evolves in step with the changing needs of the optical communication industry.
The competitive landscape for submarine cable sealing is increasingly favoring manufacturers with demonstrated expertise in metal seal technology and rigorous quality control processes. Network operators and system integrators are prioritizing reliability over cost minimization, recognizing that seal failure costs far outweigh any initial procurement savings. This trend benefits established manufacturers like Raido Sealing Products (Wuxi) Co., Ltd, which has built a reputation for quality and reliability over two decades of operation. The company'squality control system ensures that every metal C-ring meets the stringent requirements of submarine optical communication applications. As the market for submarine cables continues to expand, the demand for high-reliability metal sealing solutions will grow correspondingly, offering significant opportunities for manufacturers with proven technology and manufacturing capabilities.
Conclusion: Metal C-Rings as the Proven Standard for Submarine Repeater Sealing
The challenges of sealing submarine repeaters in deep-sea environments are among the most demanding in the entire field of sealing technology. High hydrostatic pressure, corrosive seawater, thermal cycling, and the requirement for 25-year service life without maintenance create a combination of stresses that few sealing solutions can withstand. Metal C-rings and spring-energized C-rings have demonstrated their ability to meet these challenges through proven performance in hundreds of submarine cable installations worldwide. The combination of high-pressure resistance, corrosion-resistant materials, negligible compression set, and low leakage rates makes them the preferred choice for critical optical communication infrastructure. For engineers and procurement professionals specifying sealing solutions for new submarine cable projects, metal C-rings offer the reliability and performance that the application demands.
Raido Sealing Products (Wuxi) Co., Ltd brings deep expertise and manufacturing excellence to the production of metal C-rings for the submarine fiber optic transmission system industry. With over 20 years of experience in high-end seal manufacturing, the company has developed specialized knowledge in material selection, precision machining, and quality assurance for mission-critical sealing applications. The company's company culture is focused on innovation, quality, and customer partnership, ensuring that each seal solution is optimized for its specific application. Raido's commitment to continuous improvement and strict quality control has earned the trust of over 1,000 clients worldwide, including major submarine cable manufacturers and network operators. When reliability cannot be compromised, metal C-rings from Raido provide the proven sealing performance that submarine optical communication systems require.
Frequently Asked Questions (FAQ)
1. What is a metal C-ring and how does it work in submarine optical communication repeaters?
A metal C-ring is a precision-engineered sealing component with a C-shaped cross-section made from high-strength corrosion-resistant alloys. In submarine optical communication repeaters, it creates a hermetic metal-to-metal seal between the housing and mating flanges by deflecting under compression and generating high localized contact stress. The internal pressure of the deep-sea environment actually enhances the sealing force by acting on the inner surface of the C-ring, making it particularly effective for high-pressure applications. This design provides reliable protection against seawater intrusion for the sensitive electronics and optical components inside the repeater.
2. Why are metal C-rings preferred over elastomeric O-rings for deep-sea repeater sealing?
Metal C-rings are preferred because they overcome the fundamental limitations of elastomeric O-rings in deep-sea environments, including compression set, extrusion, chemical degradation, and thermal sensitivity. Unlike elastomers, metal seals maintain their sealing force over decades without relaxation and are not susceptible to hydrolysis or chemical attack from seawater. They also resist extrusion under high hydrostatic pressure because the metal material has comparable strength to the housing components. The total cost of ownership is lower despite the higher initial cost, because metal C-rings eliminate the risk of costly seal failures and mid-life repairs in submarine cable systems.
3. What makes spring-energized metal C-rings suitable for high-pressure underwater environments?
Spring-energized metal C-rings incorporate an internal spring element that provides continuous outward pressure on the sealing lips, ensuring consistent contact pressure even under thermal cycling or minor housing deformation. The spring compensates for differential thermal expansion between seal and housing, maintains sealing force during pressure fluctuations, and tolerates minor surface irregularities. This design achieves helium leak rates below 1 × 10⁻⁹ mbar·L/s, which is essential for preventing water vapor diffusion that can degrade optical performance. Raido's spring-energized metal C-rings are specifically engineered to meet the demanding reliability requirements of submarine fiber optic transmission systems.
4. How does thermal cycling affect metal C-ring performance in submarine cables?
Thermal cycling in submarine cables causes repeated expansion and contraction of the repeater housing and seal components as temperatures change between cold ocean water and elevated operating temperatures. Metal C-rings are inherently resistant to thermal cycling effects because their coefficient of thermal expansion can be closely matched to the housing material, minimizing differential stress. The spring-energized design further compensates for thermal movements by maintaining consistent sealing force throughout the temperature range. This thermal stability ensures that the seal remains leak-tight across all operating conditions, unlike elastomeric seals that can develop intermittent leakage paths during temperature transitions.
5. What materials are used in metal C-rings for corrosion resistance in seawater?
The most common materials for metal C-rings in submarine applications are Inconel 718 and 316L stainless steel, both of which offer excellent corrosion resistance in chloride-rich seawater. Inconel 718 provides superior strength and resistance to stress corrosion cracking at elevated temperatures, making it ideal for high-performance repeater applications. These alloys are selected for their resistance to pitting, crevice corrosion, and general corrosion over decades of continuous seawater exposure. Raido also offers custom material solutions for specific application requirements, ensuring optimal corrosion resistance and mechanical properties for each sealing application.
6. What is the typical lifespan of a metal C-ring in a submarine repeater housing?
Metal C-rings are designed to last the full service life of the submarine repeater, which is typically 25 years or more without maintenance. The combination of corrosion-resistant materials, minimal compression set, and robust mechanical design ensures that sealing performance remains stable over this extended period. Field data from existing submarine cable installations confirms that properly designed and installed metal C-rings can maintain hermetic sealing for decades. This long service life is a key factor in the economic viability of submarine optical communication systems, as it eliminates the need for costly mid-life repairs or premature cable replacement.
7. How does Raido ensure quality control in manufacturing metal C-rings for optical communication systems?
Raido Sealing Products (Wuxi) Co., Ltd implements a comprehensive quality control system that covers every stage of manufacturing, from raw material inspection to final leak testing. Each metal C-ring undergoes rigorous dimensional inspection, surface finish verification, and helium leak testing to ensure it meets the specified leakage rate requirements. The company's quality control processes are certified to international standards, and all test results are documented for full traceability. Raido's commitment to quality is backed by over 20 years of experience in manufacturing high-end metal seals for critical applications across multiple industries.
8. Can metal C-rings be used for both internal pressure and external pressure applications in submarine cables?
Yes, metal C-rings are designed to seal effectively in both internal pressure and external pressure applications, making them versatile for various submarine cable components. For external pressure applications common in submarine repeaters, the hydrostatic pressure acts on the outer diameter of the C-ring and enhances the sealing force. For internal pressure applications, such as pressure vessels that contain pressurized electronics or optical components, the C-ring can be oriented to use internal pressure to improve sealing. Raido offers different C-ring configurations optimized for internal pressure, external pressure, and axial pressure applications, with detailed selection guidance available on their product pages.
9. What groove design considerations are important for installing metal C-rings in repeater housings?
Groove design for metal C-rings requires precise control of depth, width, corner radii, and surface finish to achieve optimal sealing performance. The groove dimensions must be calculated to provide the correct compression percentage for the specific C-ring alloy and geometry, typically ranging from 15% to 25% of the seal cross-section height. Surface finish of the groove and mating flange should be 0.4 μm Ra or better to ensure effective metal-to-metal contact. Raido provides detailed groove design recommendations and engineering support to ensure that each seal application achieves the required leakage rate and service life.
10. How does the market growth of fiber optic communication drive demand for metal sealing solutions?
The rapid expansion of global data traffic, driven by cloud computing, 5G networks, and streaming services, is fueling unprecedented investment in new submarine cable systems. Higher-capacity fiber optic transmission systems require more repeaters per cable route and more complex repeater architectures with additional sealing interfaces. The demand for reliable long-life sealing solutions grows proportionally with the number of repeaters deployed, creating sustained market growth for metal C-ring manufacturers. As network operators prioritize reliability to minimize service disruptions and repair costs, the adoption of proven metal sealing technology in new submarine cable projects continues to accelerate globally.