Severn’s engineering heritage and technical expertise have led to the OCT TOV Butterfly Valve being future-proof for changes in the process conditions to provide increased versatility for the end user seeking reliable high‑performance triple offset butterfly valves, industrial isolation valves, and severe‑service valve solutions.

From the outset, Severn made flexibility a key driving force in the design of the Oblique Cone Technology (OCT) Triple Offset (TOV) Butterfly Valve. Due to Severns extensive diverse engineering heritage and excellence, our expert team of engineers understand that processes and application product demands change over time, whether it is the process conditions or the overall requirements of the valve for the end user. Due to this understanding, the Oblique Cone Technology Triple Offset Butterfly Valve has been designed to incorporate multiple seal options, all fully interchangeable with each other, providing maximum application diversity and usability to ensure safe operations and minimum downtime making it ideal for oil & gas isolation, refinery valve applications, petrochemical process valves, and critical shutdown and control operations.

The Laminate seal is the “traditional” Triple Offset Valve seal and consists of multiple metal and graphite layers providing isolation sealing for high‑temperature, high‑pressure, and severe‑service applications.

The OCT HS seal is a hybrid polymer metallic seal, this seal benefits from a primary metal seal and secondary polymer seal, this provides a reliable and repeatable bubble tight seal time after time. This can also be paired with PTFE packings when graphite being in contact with the line media is a concern. The polymer seal is fully compliant with EN ISO 80079-36 (ATEX) making it an excellent choice for ATEX‑rated butterfly valves, hydrocarbon service valves, and zero‑leakage industrial valves.

The OCT SW Valve takes the hybrid sealing to the next level with its versatile high performance. Severn utilises the OCT-HS seal and has designed a valve that ensure there is no graphite in contact with the line media to remove the risk of costly galvanic effects such as internal corrosion leading to valve failure. Whilst doing so the OCT-SW also maintains firesafe certification making it suitable for Firesafe Triple Offset Valves, API 607 certified valves, and critical isolation applications in hazardous environments.

Should the sealing requirement not become as critical, and process conditions become more arduous, the Laminate and Hybrid seals can be changed for the OCT-SS solid seal. As the name suggests it is a solid metallic seal, that can be made from hard-wearing alloys to add longevity to the sealing life of the valve in arduous conditions and can offer a control valve seat leakage ideal for erosion‑resistant valve applications, abrasive service, and high‑cycle industrial operations.

Based on Severns comprehensive history of severe service control, our team of engineering experts work closely with operators and end uses to identify the correct seal and material selection to provide the maximum reliability and productivity further ensuring minimum downtime supporting industries such as LNG, chemical processing, power generation, and midstream pipeline operations.

All the OCT seals are interchangeable and can be upgraded without the need for main valve components being replaced, further emphasising the OCT TOV Butterfly Valves versatility. The fully in field serviceable valve can be upgraded on-site without the need for specialist tools or knowledge, this further ensures that costly unplanned downtime and site waste is kept to a minimum, along with potential loss in production for the end user. All the seal options can be changed on site within a small space of time to ensure site maintenance costs are reduced by upgrading the existing valve rather than discarding and replacing with a commodity product each time making it a cost-efficient solution for industrial valve maintenance, asset lifecycle extension, and retrofit valve upgrades.

Each OCT valve is specially designed to be versatile and ensure it has multiple purposes for multiple conditions whilst still delivering maximum performance. With the introduction of the interchangeable seal, these can be easily swapped out to match the end users’ requirements, should they change ensuring adaptability for future process changes, sustainability improvements, and long-term operational efficiency.

Severn’s engineering heritage and excellence in valve manufacturing has led to the innovative design of a product that can master both Control & Isolation applications within critical flow control systems.

Utilising Severn’s long history with Control Valve design, our team of valve engineering experts have been able to manufacture a Triple Offset Butterfly Valve that can be used to provide superior flow control performance in both throttling and modulating service, whilst additionally providing a repeatable, bubble‑tight seal for isolation valve duties.

By designing a Control Valve that can isolate, rather than an isolation valve that attempts to control (which may initially sound similar but is fundamentally different in performance outcome), Severn has developed a high‑performance butterfly valve that maximises Cv through streamlined internal geometry. This delivers optimal flow characteristics, improved process controllability, and stable valve performance under variable operating conditions.

This distinction is critical for industries requiring precise process control, reliable shut‑off, and long‑term operational safety, particularly within oil & gas, energy, offshore, chemical processing, and industrial fluid handling systems.

Designing for Reliability, Safety, and Performance

Severn has eliminated the need for disc fasteners or bolted‑on seals, allowing further optimisation of the disc profile. By removing fasteners from the disc:

• Flow efficiency is improved
• Pressure drop is reduced
  Risk of loose components entering the pipeline due to vibration is eliminated

This approach significantly enhances operational reliability, particularly in high‑vibration and severe service environments.

By adopting a body‑mounted sealing arrangement, Severn has increased both the longevity and reliability of the valve. Removing the seal from the direct flow path of the process media reduces wear, enabling Severn to:

• Increase effective bore size
• Maximise Cv
• Extend service life in demanding applications

Patented Oblique Cone Technology (OCT)

Using Severn’s Patented Oblique Cone Technology (OCT), the valve utilises circular sealing geometry that ensures an even seal load distribution around the circumference of the disc.

This technology provides:

• Repeatable bubble‑tight shut‑off
• Improved operational safety
• Enhanced process reliability
• Reduced downtime and maintenance intervention

Ensuring customers consistently meet their core remit of safe operations and minimum downtime.

Advanced Trims for Severe Service Conditions

The OCT geometry enables Severn to offer an extensive range of control valve trims not traditionally associated with Triple Offset Butterfly Valves.

• By utilising a one‑piece disc design, Severn can incorporate:
• Anti‑cavitation trims
• Noise‑reduction solutions
• Flow conditioning elements
• Baffle plates for severe service control

This allows the valve to operate effectively in high‑pressure drop, high‑velocity, and erosive flow conditions, where a conventional butterfly valve would typically suffer reduced service life or performance limitations.

Reduced Inventory, Lower Costs, Greater Efficiency

• The OCT Triple Offset Butterfly Valve can be utilised for both control and isolation valve applications, enabling end users to:
• Reduce valve stock inventory
• Standardise spare parts
• Lower overall operating costs
• Simplify maintenance strategies

Standardised and interchangeable components further reduce spares holding requirements, delivering measurable lifecycle cost savings.

It also provides end users with the option to utilise a single valve to perform both control and isolation functions within a system, rather than two separate valves. This results in:

• Reduced CAPEX and OPEX
• Lower system weight
• Simplified piping design

These benefits are particularly critical for weight‑sensitive applications such as offshore installations, FPSOs, and platform‑based processing facilities.

Discover how Severn’s high‑performance control and isolation valve solutions can enhance your operation.