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Pressure Rated Flanges

This line of MARZOLF™ Class 150 Pressure Rated Two-Piece Flanges is developed as an improved two-piece lap joint flange offering considerable safety and ease of installation over existing products currently in use.

During the development process, it was determined that there is no specific standard written for a flange design such as the Marzolf Flange.  The ASME B31.3 Piping Code does allow the use of “non-listed components” providing that they fulfill the intent of the listed components.

Marzolf Pressure Rated Flanges have extensive and successful service experience for ASME pressure rated applications since 2014; and for standard applications under comparable conditions, with similarly proportioned components of the same or like material since 1955.  This extensive and successful service satisfies the ASME B31.3 (304.7.2) requirement for use as an unlisted component.

Each flange is designed according to the ASME BPVC, Section VIII, Division I Mandatory Appendix 2. Rules for Bolted Flange Connections with Ring Type Gaskets.

The required thickness of each flange is calculated following specific design procedures to meet the design pressure and temperature conditions.

A copy of the calculation procedure can be provided upon request.

They are sized to fit:

  • IPS Stub Ends
  • IPS Angle Rings
  • Ductile Iron Pipe (DIPS)

MARZOLF™ Pressure Rated Class 150 Interlocking Split Flanges save money and reduce downtime by eliminating the need to cut and reweld piping when installing or replacing Lap Joint flanges and backing rings behind Stub Ends, Slip-On Angle Face Rings, and Ductile Iron Pipe.

These rings are available in:

  • Stainless steel
  • Most alloys
  • Carbon steel

All with different corrosion-resistant coatings including Zinc Electro Plate and E-Coat Epoxy.

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