What is ring joint gasket?
The Ring-Type joint metal gaskets (also called RTJ gaskets or API joint gaskets) are heavy duty, high-pressure gaskets largely used in offshore and onshore petrochemical industry, oil-field drilling and completion equipment, and in valves and pipework assemblies, along with some high integrity pressure vessel joints.
What is the role of gasket in flange joint?
Flange gaskets are used to create a static seal between two flanges faces, at various operating conditions, with varied pressure and temperature ratings. A gaskets fills the microscopic spaces and irregularities of the flange faces, and then it forms a seal that is designed to keep liquids and gases.
Can you reuse ring joint gaskets?
Ring joint gaskets are designed to have a limited amount of positive interference, which ensures that the ring type joint seats correctly into the groove on compression. Their reuse is not recommended for two reasons: The initial seating of the gasket will be impaired.
What type of gasket is used with a RTJ flange?
The gasket used is a steel ring – instead of the flat composite material type. An RTJ flange has a groove machined into the flange surface to accept the gasket.
Do flanges need gaskets?
The full-face gasket is typically used with flat face flanges but can also be used with RF flanges. It sits on the raised flange faces but has the same outside diameter of the flange. For that reason, it has to have holes for the bolts securing the flanges to pass through.
Can you reuse flange gaskets?
Once a gasket has taken a set (due to temperature and fluids), it should not be disturbed or reused. It would not have the same properties available to go through the initial compression provided by the joint and achieve the initial seal.
What is the difference between oval and octagonal ring gasket?
The octagonal type has a higher sealing coefficient than the oval. Flanges with Octagonal grooves or flat bottom grooves will accept either style. The oval type is the only type RTJ that will fit oval or radius grooves. Gaskets should not be reused once torqued.
What are the different types of flange gaskets?
The three primary types of Flange Gaskets are Non-metallic, Semi metallic and Metal Gaskets. The Non-metallic Flange Gaskets are used in low pressure, low temperature and noncritical service applications.
How do I choose a gasket for my flange?
Gasket Thickness As a rule of thumb, the gasket should be at least four times thicker than the maximum surface roughness of the flange faces. The gasket must be thick enough to occupy the shape of the flange faces and still compress under the bolt load.
Which material is used for gasket?
Gaskets are normally made from a flat material, a sheet such as paper, rubber, silicone, metal, cork, felt, neoprene, nitrile rubber, fiberglass, polytetrafluoroethylene (otherwise known as PTFE or Teflon) or a plastic polymer (such as polychlorotrifluoroethylene).
What type of standard ring joint gasket is superior?
octagonal ring gasket
While it is generally recognized that the octagonal ring gasket is a superior design that offers higher sealing efficiencies and reliability, oval gaskets still comprise about 90% of the market.
What is ring type joint?
A ring type joint is a specialised gasket, designed to be used with flanges that have grooves in them. The advantage of this type of gasket is that it is made of metal and so creates a seal that is very strong and reliable. It will withstand the pressure of up to 1500 Bars and temperatures of up to 1000° Centigrade.
What thickness gasket do I need?
On the downside, thinner gaskets will not seal as many flange irregularities as thicker gaskets, and require flatter flanges. The most commonly used thicknesses for Standard Flange gaskets are 1/16″ and 1/8″.
What are PTFE gaskets?
PTFE gaskets are made of synthetic fluoropolymer of tetrafluoroethylene consisting completely of carbon and fluorine. It is innately hydrophobic (repelling water and water-containing substances) and has one of the lowest coefficients of friction against any solid.
What are the types of flange gaskets?
Types of flange gaskets: Standard pipe flange gasket line includes two basic styles: Ring Type and; Full Face; Both ring type and full face pipe flange gaskets are available in both low and high pressure options.
What gasket thickness should I use in my flange system?
Apply a continuous bead of silicone to the mating surface.
How to select the right flange gasket?
Flange face type and dimensions
How to bolt a flange?
Locate the bolts: These bolts can easily be found once the car is jacked up.