An insert flange is a two-piece flange consisting of an insert and a flange. It is similar in concept to the standard lap-joint and stub-end flange. Insert flanges are of far superior quality, however. The insert is made to the material of the main process pipe, which is usually 316/316L or 304/304L stainless steel. All pipe, whether for jacketed or single pipe applications, welds to the insert. The flange is usually made out of A-105 or Pressure Vessel quality 515/516 Grade 70 Carbon Steel and serves as a rotatable bolting ring for the insert. The insert and flange can be made out of any machinable alloy. We regularly have made insert flanges out of Alloy 20, Duplex Alloys, Nickel Alloys such as various grades of Hastelloy (C276, C22, B-3), and Aluminum.
One popular question about our product is, “what is the difference between our ASME Rated Line and our Conventional Line or Standard Thickness Line of insert flanges?” ASME B16.5 flange code is written for one-piece flanges. An insert flange is a two-piece flange. Therefore, the ASME Rated Line are engineered to a slightly thicker dimension for the thickness/length to assure full compliance with all pressure temperature ratings at the corresponding weight class. While the Conventional Line is made to the standard ASME flange thickness. For example if a standard 6″ slip-on flange was made to 1″, our Conventional Line would be made to a thickness of 1″, however, our ASME Rated Line would have an engineered thickness of 1.19″. A few sizes are actually identical in ASME and Conventional, however, the answer to the original questions is: Our ASME and Conventional Lines are the same except for an occasional variance in the thickness of the flange which also affects the overall thickness of the insert. We continue to offer both lines because there are many old plants that we service where the Conventional Line works perfectly for the conditions. However, we recommend using the ASME Rated Line for all new applications.
Click on one of the pictures below to view more about our Insert Flanges for Jacketed Piping or Single Piping…