Royle Reflect on the Development of CCV Technology: Extruding continuous innovations since 1855

Mr. Reji Koshy Daniel, Executive Director, Royle Extrusion Systems Private Limited (wholly owned subsidiary of Royle Systems Group (USA)) shares that today’s cable industry is characterized by a wide range of insulation materials and manufacturing technologies, each developed to address specific application requirements. Royle with its 7 decades of experience in manufacturing and supplying CCV lines, has overcome several challenges in the extrusion and curing processes and enabled the development of high-performance, quality cables. He further emphasized that as the demand for high-performance cables continues to grow across renewable energy, transportation, mining and industrial sectors, the CV and CCV technology has become a foundation of modern cable manufacturing.

Since our founding in 1855, Royle has developed process and machinery innovations which have contributed to the growth of industry in the rubber and cable sectors. Royle patented the world’s first screw type extruder in 1885, which revolutionized the process of cable manufacturing in the world. Royle, in cooperation with the Western Electric Division of Bell Telephone, pioneered the continuous vulcanization (CV) process for insulation of rubber cables in 1938.

Royle patented the Catenary Continuous Vulcanization (CCV) process in 1958, which is still, nearly 70 years later, the primary foundational process for the manufacture of cables for many applications and range of voltage from LV to EHV.

As an insulation material, rubber and its thermosetting variants provide many advantages for cable insulation, including excellent flexibility, resistance to mechanical fatigue and reliable performance in demanding operating environments. These characteristics make it suitable for applications where cable movement, vibration and physical abuse are required.

Rubber compounds require vulcanization after extrusion onto cables to achieve their final physical properties. Traditionally, before CV, this was a separate batch process after extrusion that required the finished cable reels to be moved to large autoclaves, where low pressure steam cured the rubber insulated or sheathed cables. Separation of curing from extrusion limited production efficiency and consistency of quality of the vulcanized cable.

Royle addressed these limitations by developing several types of CV processes, which integrated extrusion and curing into one process. This overcame the limitations of the separate extrusion and curing processes and provided significant improvement in efficiency of performance, quality of cable and control of process. Over the years, CV and CCV became a foundational technology of modern cable manufacturing.

New materials and manufacturing technologies are often introduced to address specific functional requirements, but foundational technologies like the Royle CV are able to adapt and serve new applications as their capabilities remain advantageous. Over the last century, the cable industry has evolved from natural rubber compounds to a wide range of high performance thermosetting copolymer elastomers. These copolymers are produced using the latest technology that allows these thermosetting materials to bridge the gap between thermoplastics and rubbers, as they combine the rubber-like qualities of flexibility, elasticity and mechanical durability of traditional elastomers. Understanding how these technologies evolved, and why they continue to coexist, provides useful insight into the direction of today’s cable market.

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The Development of Steam Cure and Dry Cure Technologies
The growth of CCV technology created opportunities for different curing methods to emerge. Steam CCV systems became the established solution for elastomeric cable production. This process provided efficient curing of rubber-based compounds and supported the manufacturing of a wide range of industrial, mining, marine and power cables.
As demand for power transmission infrastructure increased, the industry adopted crosslinked polyethylene (XLPE) and ethylene propylene rubber (EPR) insulation for medium voltage (MV) and high voltage (HV) applications. These materials offered attractive electrical properties and became increasingly important as power networks expanded around the world.

This shift contributed to the development and adoption of Dry Cure technology, which uses nitrogen as the pressurizing medium and radiant heat for curing instead of high pressure steam. Dry Cure became widely used for XLPE and EPR insulation, as these materials withstand higher curing temperatures, so Dry Cure improves productivity and overcomes potential disadvantage of moisture from curing in steam.

The growth of Dry Cure CCV technology is sometimes viewed as a transition away from rubber and steam CCV. In fact, steam CCVs for rubber cables are actually a growth sector. Dry Cure is a diversification of CV technology to embrace new materials and applications.

The Dry Cure CCV has been further developed to the Dry Cure – Dry Cool CCV with nitrogen also used as the cooling medium for High Voltage (HV) and Extra High Voltage (EHV) cables, which positively eliminates water-treeing during the vulcanization process. The elimination of water cooling also saves gallons of water, an environmental side benefit

Rather than replacing Steam CCV technology, Dry Cure – Dry Cool CCV technology expanded the industry’s capabilities to process new insulation materials by using new curing technologies. The CCV process evolved to serve different performance requirements and created a broader range of manufacturing options for cable producers.This development of CCV technology can be visualized as a tree. The CCV process developed by Royle is the trunk, while the development of Steam CCV and Drycure CCV are two branches that have evolved to support market demand for new materials and applications.

Why Rubber Still Remains Important
Despite the growth of XLPE-based power cable production, demand for rubber-insulated cable has remained strong and is experiencing renewed growth in several sectors.

Recent market research reflects that trend. According to DataIntelo, the global rubber insulated cable market was valued at USD 12.8 billion in 2025 and is projected to reach USD 22.6 billion by 2034, representing a compound annual growth rate (CAGR) of 6.5%. The study also reports that low-voltage cable applications accounted for 52.4% of market demand in 2025, while Asia-Pacific represented 38.5% of global market revenue. These figures fit within a broader expansion of the cable industry.

Analysis by Global Market Insights estimates the global wire and cable market at USD 267.8 billion in 2024, with projected growth of 7.3% CAGR through 2034. Similarly, Fortune Business Insights forecasts the global power cable market to grow from USD 252.7 billion in 2026 to USD 414.7 billion by 2034, driven largely by grid modernization, electrification and renewable energy investments.

The data suggests that rubber is not simply maintaining a legacy position within the industry—it is growing alongside wider investments in electrification, infrastructure and energy transition projects. One reason is that the properties that made rubber attractive historically remain difficult to replicate in many demanding applications.

Mining and Industrial Applications
Mining cables, trailing cables and welding cables operate in some of the harshest environments encountered by electrical systems. These products are frequently dragged across abrasive surfaces, exposed to impact, wound onto reels and subjected to repeated flexing. In many cases, elastomeric insulation and sheath compounds remain the preferred solution because they provide the combination of flexibility, toughness and durability required for reliable operation. For many mining, welding and trailing cable applications, rubber remains the benchmark against which alternative insulation systems are measured.

Renewable Energy
The continued growth of renewable energy projects has also increased demand for robust cable systems. DataIntelo identifies renewable energy investment as one of the principal drivers of growth within the rubber-insulated cable market. Offshore wind installations, for example, expose cables to moisture, salt, ultraviolet radiation, ozone and continuous mechanical stress. Elastomeric materials are often selected because of their ability to withstand these conditions over extended service lives.

The broader market outlook supports this trend. According to the International Energy Agency (IEA), global renewable energy capacity additions between 2025 and 2030 are expected to reach approximately 4,600 GW, representing one of the largest infrastructure expansions in the energy sector’s history. As renewable energy projects move into increasingly demanding environments, durability and environmental resistance become as important as electrical performance.

Electric Vehicles and Transportation
The transportation sector is another area where elastomeric materials continue to play an important role. DataIntelo also identifies electric vehicle manufacturing as a major driver of demand for rubber-insulated cable.

Electric vehicles require cable systems capable of tolerating vibration, movement and elevated operating temperatures while maintaining long-term reliability. Materials such as EPR, EPDM and silicone rubber are increasingly used in applications where flexibility and durability are important performance requirements. This trend is expected to continue. According to the International Energy Agency, global electric vehicle sales are projected to exceed 20 million units in 2025, accounting for more than one quarter of all new vehicle sales worldwide.

As transportation becomes increasingly electrified, demand is growing for cable systems capable of operating reliably in compact, high-temperature and highly dynamic environments.

New Considerations for Cable Manufacturers
As cable markets become more specialized, manufacturers are increasingly required to support a diverse range of products and applications. Selecting the correct manufacturing technology depends on several factors, including cable design, insulation material, target markets and long-term production objectives.

Producing high-quality elastomeric cable requires more than extrusion capacity alone. Compound behavior, curing characteristics, process control and line configuration all influence product quality and manufacturing efficiency. Successful elastomeric cable production depends as much on process knowledge as it does on equipment selection.

For this reason, manufacturers entering or expanding elastomeric cable production often seek technology partners with experience across both equipment design and material processing. At Royle, our experience spans more than 140 years of cable manufacturing technology development and hundreds of CV installations worldwide. Our systems support a wide range of elastomeric insulating and sheathing materials, including EPR, EPDM, CSP, PCP, silicone rubber and other specialized compounds, by applying tandem, single-layer, dual-layer and triple-layer extrusion configurations.

By working closely with cable manufacturers during the selection of a CV line, design and commissioning, Royle helps to ensure that production systems are aligned with both current requirements and future plans for growth.

Looking Ahead: Is CCV In Your Future?
Today’s cable industry is characterized by a wide range of insulation materials and manufacturing technologies, each developed to address specific application requirements.

CCVs will continue to play a central role in all sectors of the cable industry, because elastomeric insulation materials remain essential in sectors where flexibility, mechanical durability and environmental resistance are critical performance requirements.

The development of cable insulation technologies has largely been additive rather than replacement-driven. Steam CCV and Dry Cure CCV technologies each occupy important positions within the industry by supporting different materials and serving different markets.

The future of cable manufacturing will NOT belong to one type of insulation system or one type of curing technology. Growth will continue to be driven by the ability of different technologies to serve different application requirements.

National and international norms are now getting stricter towards Industry 5.0 priorities. Institutions are now mandating stringent process and performance control that can be achieved only by advanced processes with due clarity in technology and care in manufacturing.

As demand continues to grow across renewable energy, transportation, mining and industrial sectors, CV technology, existing and new, is a necessary component of the global cable manufacturing landscape.

Also Read: WOYWOD: Real-time Monitoring of Material Flow at Screw Dosing Units Using Ultrasonic Sensors

References
DataIntelo, Global Rubber Insulated Cable Market Report, 2025.
International Energy Agency (IEA), Global EV Outlook 2025.
International Energy Agency (IEA), Renewables 2024 Market Report.
Global Market Insights, Wire and Cable Market Analysis.
Fortune Business Insights, Power Cable Market Report.