Knowing the diameter of the stainless steel flange, how to determine the size of the gasket
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Knowing the diameter of the stainless steel flange, how to determine the size of the gasket (gasket with reinforced polyethylene PTFE layer)? Flange diameters: (φ130mm), (φ190mm), (φ165mm), (φ135mm), (φ100mm)
Standard flanges go with standard gaskets; I’m not sure about non-standard ones
Check the flange standards; if they match, use the standard gasket. If it doesn’t fit, then avoid the inner hole of the pipeline and the bolt holes.
In accordance with the HG/T 20592-2009 standard, the type of sealing surface on the flange should correspond one-to-one with the type of gasket used
The data is not comprehensive enough; it is necessary to know the pressure and nominal diameter of the flange in order to make a determination. Moreover, different types of sealing surfaces require different gaskets for pairing. Providing only one outer diameter value only allows for speculation.
First, check the standards to see if it belongs to standard flanges. If it is a non-standard flange, the gasket size can only be determined based on the position of the sealing surface. The inner diameter of the gasket should be determined based on the innermost (smallest) diameter of the flange ； Generally, there are water ripple lines in the middle of the sealing surface; remember that the inner and outer diameters of the polyethylene-tetrafluoroethylene portion of the gasket must match those of the sealing surface. The outer diameter of the gasket must be slightly smaller than the inner diameter of the bolt hole, so that when the bolts are inserted to tighten the flanges, the gasket can be easily placed in position and aligned accurately.
Check what diameter the flange is for, that is, the DN. It means using the same flange with the same gasket. Gaskets that match the flanges
It is necessary to know the inner diameter of the pipe (outer diameter of the pipe minus wall thickness); it should match the inner diameter of the gasket. If the outer diameter blocks the bolt holes, simply cut them out
Many stainless steel flanges have an outer diameter of -5 and a thickness of -3. With the parameters you provided, it’s not possible to determine the size of the flange. It’s then impossible to obtain the gasket. Standard flanges generally correspond one-to-one with gaskets.
If it is a flange for chemical applications, refer to GB/T20615-2009; all the dimensions of the flange can be found there, which allows one to determine the type and size of the gasket.