Understanding Triple Offset Butterfly Valves

There are different types of valves in the market, and choosing the right valve is important for engineering processes and operations. A butterfly valve comes in three different types based on the number of offsets, namely, zero offsets, double offset, and triple offset.

Triple offset butterfly valves (TOVs), also called high-pressure butterfly valves, are perfect for offshore and upstream gas and oil industry applications. It is specifically used in the turret and topside applications of Floating Production Storage and Offloading vessels, gas compressions, separators and water treatment plants.

The triple offset valves were introduced in the 1970s in India as a significant improvement over the traditional butterfly valves, and it was a success since its inception. It evolved as a robust, effective and reliable alternative to gate and ball valves. TOVs come in different sizes, materials and rating, making them very useful for different applications. Triple offset valves are used in similar industries as the gate valves and double offset butterfly valves but for more demanding applications like super-heated steam, high-pressure steam, and high-temperature oil and gas. A study indicates that there are over half a million TOVs installed across the world.

Are Triple Offset Valves An Effective Solution For Gas And Oil Applications?

The oil and gas industry faces the unique challenge of operating in harsh conditions. The oil rigs and wells have extreme temperatures greater than 816 degrees and pressure more than 25k psig. The operating conditions can sometimes be cryogenic, with temperatures below -162 degrees. Valves used in the gas and oil fields need to perform well throughout the operation of a well's life. It needs to regulate upstream, downstream and midstream operations.

Upstream - Valves are used to control the upstream flow of natural gas and crude oil.

Downstream - Includes crude oil refinement and delivery of petrol products. Here, the valves should handle high temperature and pressure found in refineries.

Midstream - Include storage and transfer of gas and oil from remote locations using long pipes fitted with valves to regulate flow and protect the equipment.

In India, triple offset valves became a big hit in the gas and oil industry. These valves are mostly used in oil and gas applications where positive isolation is required with high to low pressure and high temperature to cryogenic.

The design is completely different from the traditional butterfly valves. TOV's valve shaft is double offset, and the conical valve seat forms the third offset. The cone tip is oriented to the asymmetrical axis of the valve. The benefit of this design is that it is torque seated and eliminates rubbing of the seat with a seal ring when it rotates ninety degrees. While choosing an actuator for TOVs, you do not have to give much importance to its safety factors as the torque remains stable all through its life. With autonomous temperature, cycles and applications, TOVs are more economical, reliable and easy to choose an actuator.

The powerful features and heavy-duty ability of TOVs are ideal for non-critical and critical upstream gas and oil applications. Traditionally, gate and ball valves were used for most of the onshore and offshore installations of flow-based isolation applications. But, today, TOVs offer an effective solution compared to any other valves.

Benefits Of Using Triple Offset Butterfly Valves

Some of the benefits of triple offset butterfly valves are:

  • It is simple and easy to install TOVs compared to ball valves.
  • It can be utilised for both control and isolation applications.
  • It has non-friction rotation compared to ball valves, and hence it offers fire safety.
  • It offers weight and space savings which are highly regarded for upstream applications.
  • It guarantees zero leakage with uniform sealing and tight shut off.
  • It offers high life expectancy and excellent performance without any temperature limitation.

Here at Oilvalve, the top valve manufacturers in India Understanding Triple Offset Butterfly Valves, we deliver high-quality butterfly valves that work in demanding conditions. Contact us if you have further queries. We will be happy to help you.