The reason why metal ring gaskets cannot be mixed casually is that as the core sealing element of flange connections, their specifications, materials, and structural forms need to be strictly matched with the sealing groove and working conditions (pressure, temperature, medium) of the matching flange. Once mixed, it is extremely easy to damage the sealing effect, cause medium leakage, and even lead to safety accidents.
From the perspective of specifications, the dimensions of different metal ring gaskets (such as outer diameter, inner diameter, cross-sectional thickness, and cross-sectional shape, commonly including octagonal, elliptical, and lens shapes) are designed according to the standards of flange sealing grooves. For example, octagonal ring gaskets correspond to trapezoidal grooves of concave convex flanges, while elliptical ring gaskets are suitable for specific sizes of mortise and tenon flanges. If ring gaskets with mismatched cross-sectional shapes or sizes are mixed, they cannot fully fit the sealing groove and will form gaps. Under high pressure or high temperature, the medium will leak from the gaps. At the same time, there are strict requirements for the machining accuracy of ring gaskets (such as surface roughness and dimensional tolerances). If there are slight dimensional deviations in the same specification ring gaskets from different manufacturers, mixing them may also affect the fit of the sealing surface.
Material adaptability is even more crucial. The material of the metal ring gasket (such as pure copper, low carbon steel, stainless steel, nickel based alloy, etc.) needs to be selected according to the corrosiveness of the medium, working temperature, and pressure – for example, corrosion-resistant 316 stainless steel ring gaskets are required for pipelines transporting acidic media, and high-temperature and high-pressure steam pipelines need high-temperature resistant nickel based alloy ring gaskets. If ordinary carbon steel ring gaskets are mixed with corrosive media, the ring gaskets will be quickly corroded, and the sealing surface will be damaged and leak; If a low-temperature material gasket is used under high temperature conditions, the gasket will soften and deform due to high temperature, lose its sealing ability, and may even cause the sealing surface to crack due to material failure.
In addition, the matching of operating parameters cannot be ignored. Each metal ring gasket has its rated pressure and temperature range (such as PN10 ring gasket cannot be used for PN40 high-pressure system). Mixing low-pressure grade ring gaskets under high-pressure conditions will cause excessive compression and deformation of the ring gasket, resulting in damage to the sealing surface; On the contrary, using a high-pressure ring gasket in a low-pressure system may not form an effective seal due to insufficient sealing preload. Even for gaskets of the same specifications and materials, if they come from different batches or have aging or damage (such as surface scratches and deformation), it is not recommended to mix them together, because the sealing performance of damaged gaskets has decreased. When used in combination with intact gaskets, the reliability of the overall sealing system will be affected.
In practical applications, it is necessary to strictly follow the design documents or flange specifications, select the corresponding model, material, and pressure level of metal ring gasket, and ensure that the new ring gasket is completely consistent with the original specifications when replacing it, to avoid mixing due to “convenient drawing” or “compatibility”. Before installation, it is necessary to check whether the surface of the gasket is clean and undamaged, and ensure that the sealing surface is free of impurities, in order to ensure the sealing and safety of the flange connection. Especially in high-risk areas such as petrochemicals, nuclear power, and high-pressure fluid transportation, the risk of mixing metal gaskets is higher and must be eliminated.
There are many types of RTJ gaskets, including R Gasket,RX Gasket,BX Gasket, SBX Gasket,IX Gasket,and various customized products.We will do more sharing about ring joint gasket.