RF vs RTJ vs BW Gate Valve

The gate valve end connection determines how the valve integrates into a piping system. Common types include Raised Face (RF), Ring Type Joint (RTJ), and Butt Weld (BW). Each type has specific mechanical advantages for various industrial environments. Hence, engineers must match the valve connection to the pipeline pressure and temperature requirements.

This guide explains the technical differences between RF vs RTJ vs BW gate valves. Choosing the correct connection guarantees leak-proof performance and system safety. 

Understanding RF Gate Valve 

A Raised Face (RF) gate valve has a circular-shaped sealing face that projects beyond the plane of the flange’s bolt circle. It is available in all pressure classes, therefore used for a wide range of pressure and temperature ratings. Furthermore, RF gate valves are the most popular type of flange used in chemical engineering as well as oil and gas industries. 

RF valves have serrated sealing surfaces that use non-metallic or semi-metallic gaskets to prevent leaks. The sealing area runs from the inner diameter of the flange to the outer edge of the raised face. Their common gasket is a graphite-steel composite gasket, which can handle temperatures up to 400°C (750°F) and pressures up to 250 bar (3625 psi).

The height of the RF depends on the class and the standard used. Under the ASME B16.5 standard, Class 150 and Class 300 steel flanges have a RF height of 1/16 inch (1.6 mm), while steel flanges above Class 300 use a 1/4 inch (6.4 mm) RF. Generally, its height may increase with pressure class, but most standards do not strictly follow this rule.

In terms of applications, standard RF valves work well in water, oil, and gas industries. However, they are not suitable for extreme high pressures. Their surface can also be damaged if roughly handled during installment or transport. 

Technical Properties of the RTJ Gate Valve

Ring Type Joint (RTJ) valves are a variation of the RF gate valve design. RTJ gate valves are commonly used for more critical applications, especially for high pressure systems and/or high temperature systems (>750°C / 1382°F). It is also possible to use RTJ valves in all pressure classes, but they are much commonly used for class 900 and above. 

The difference between an RTJ and RF valves is the way the seal is obtained. Metal (hard) gaskets are used with RTJ gate valves, while RF gate valves use soft or semi-metal gaskets. Although there are three main groups of ring type joints, including R, RX, and BX, we will focus more on the type R joint as it is by far the most common. 

RTJ Type R gaskets are circular with oval or octagonal profiles, with the octagonal shape providing the most effective seal and modern design. The gasket sits in a machined groove on the flange face and compresses during assembly to form a metal-to-metal seal. Proper installation prevents the two RTJ valve faces from touching.

Characteristics of the BW Gate Valve 

A Butt Weld (BW) gate valve features ends that are beveled for welding directly to the pipe. This connection removes flanges, bolts, and gaskets entirely. This then creates a continuous and permanent metal joint between the valve and the pipeline.

BW gate valve ends provide the strongest possible connection for high-heat systems. They are common in power plant steam lines and high-pressure chemical reactors. The lack of flanges also reduces the overall weight of the piping system.

Unfortunately, maintenance is more difficult for BW valves since they must be cut out for repair. However, they offer zero leakage potential at the connection point. Engineers usually choose BW gate valves when joint integrity is more essential than ease of removal.

RF vs RTJ vs BW Gate Valve: A Comparison Table

RF vs RTJ vs BW Gate Valve Dimensions Chart as per ASME B16.10

Conclusion

Selecting the right RF vs RTJ vs BW Gate Valve ensures long-term system integrity and safety. RF connections provide easy installation for standard pressure, while RTJ offers a metal-to-metal seal for high-pressure oil service. BW, meanwhile, eliminates gaskets entirely therefore creating a permanent, leak-proof joint for extreme thermal environments. 
YKY manufactures a diverse selection of gate valves with various end connections to meet specific project needs. Our technical team understands different applications, ensuring each valve withstands the required pressure and temperature limits. You can learn more about their engineering expertise on our about page to find the best connection for your piping system.

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