Octagonal Ring
Dimensions for standard ring joint gaskets and grooves are covered in ASME B16.20 and API 6A, API 17D and ASME B16.5/B16.20.
WELL manufactures and supplies a large variety of ring joint gaskets. The RTJ standard size gaskets are manufactured in accordance to API-6A and ASME B16.20 specifications. Rilson is licensed by the American Petroleum Institute (API).
Octagonal Ring Joint Gaskets and Oval Ring Joint Gaskets
Ring joint gaskets come in two basic types, an oval cross section and an octagonal cross section. These basic shapes are used in pressures up to 42MPa. The dimensions are standard- ized and require specially grooved flanges.
The octagonal cross section has a higher sealing efficiency than the oval and would be the preferred gasket. However, only the oval cross section can be used in the old type round bottom groove. The newer flat bottom groove design will accept either the oval or the octagonal cross section. The sealing surfaces on the ring joint grooves must be smoothly finished to 63 micro inches and be free of objectionable ridges, tool or chatter marks. RTJ assemblies seal by an initial line contact or an edging action as the compressive forces are applied. The hardness of the ring should always be less than the hardness of the flanges to prevent flange deformation. Dimensions for standard ring joint gaskets and grooves are covered in ASME B16.20 and API 6A, API 17D and ASME B16.5/B16.20.
