Ring Joint Gaskets: Types, Uses & Selection Guide

A Ring Type Joint Gasket is a precision cut or forged metal ring which fits into the RTJ groove on a mating flange. The gasket is compressed against the surfaces of the flange grooves during flange assembly, thereby forming a tight seal to prevent any loss of process fluid from the flange connection. Unlike soft gaskets and spiral-wound gaskets, RTJ gaskets are based on controlled deformation and contact between the metal gasket and the machined flange groove. They are thus widely used under pressure and temperature extremes. Metal Ring-Joint Gaskets are covered by ASME B16.20, which include materials, dimensions, tolerances, and markings. The standard also provides for dimensional suitability of referenced flange standards such as ASME B16.5, ASME B16.47 and API 6A.

The main RTJ profiles covered in this discussion are R Type, RX Type, and BX Type.

The identification numbers for RTJ gaskets relate to flange size, pressure class, and the applicable flange standard. ASME B16.20 provides separate dimensional tables for R, RX, and BX ring gaskets.

The R Type Ring Type Joint Gasket is a basic and widely used RTJ design. It is available with oval or octagonal cross-sections and is selected for compatible RTJ flange connections.

R Type Oval and Octagonal

ASME B16.20 sets a maximum surface roughness of 1.6 μm (63 μin.) for the sealing surfaces of R-type gaskets.

The modified asymmetric profile of the RX Type Ring Joint Gasket provides better sealing properties. It is self energising, and its profile is designed in such a way that the internal pressure can help to maintain sealing contact during operation. This design may be useful in application with pressure fluctuation, vibration and mechanical stress.

The gasket number and flange configuration should be verified before making a selection, as ASME B16.20 specifies dimensions for RX gaskets.

BX type Ring Joint Gasket is specially adapted for flange connections in accordance with API 6BX and is used with high pressure applications. It cannot be used as a replacement for R or RX gaskets as the groove and dimensional configuration is different. One important feature of the BX profile is its pressure equalisation hole/channel, which facilitates the equalisation of the pressure in the gasket arrangement. Depending on the flange and gasket specification, BX gaskets can be specified for pressures of up to 20,000 psi. They don't fit into R and RX grooves. The maximum surface roughness for BX sealing surfaces is 0.8 μm (32 μin.) as per ASME B16.20.

In most applications, RTJ gaskets are chosen for use in situations where pressure, temperature, and process conditions are demanding enough to warrant the use of a metallic gasket design.

Common applications include:

When sourcing RTJ gaskets, buyers should provide the flange standard, gasket type, gasket number, pressure class, material, operating temperature, and process media to the Ring Type Joint Gasket Suppliers. Providing these details helps the supplier identify a gasket that matches the flange configuration and service requirements.

Consider these factors:

ASME B16.20 specifically provides dimensional and tolerance tables for R, RX, and BX gasket types, making the applicable standard an important reference during selection.

The table summarizes the distinctions; actual selection should always be checked against the applicable flange and gasket standard.

Businesses that source RTJ sealing products must take into account their suppliers' ability, dimensional accuracy, material options, and quality control. Ordinem Engitech Pvt. Ltd. manufactures Ring Type Joint Gasket that are available in various configurations such as R, RX and BX and are provided in low carbon steel, 304, 316 and 347 stainless steel material. Customers can consult with the salesperson with regard to the type, material, size, pressure class and use conditions of the gasket to choose the appropriate sealing solution. The company is a reliable Ring Type Joint Gasket Manufacturers that emphasizes consistency in the quality of the products and manufacturing based on the requirements and specifications.

Ring Type Joint Gasket is a special type of metallic gasket which is used to seal an RTJ flange pair. Understanding the differences between R, RX and BX are important as each profile needs different dimensional and flange compatibility. R gaskets are available in oval and octagonal gaskets, RX is the modified profile for self-energising gaskets and BX is the special profile for API 6BX high-pressure flange connections. The highest pressure rated gasket is not necessarily the best gasket. The gasket needs to be the same as the flange, in terms of standard, pressure, process medium, material, dimension, and flange. Buyers should check the relevant specification and technical documentation before going for procurement for critical applications.