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Download a Minnesota Special Application

A Minnesota special application is for boilers or pressure vessels constructed prior to 1957. These vessels may not have ASME certification or registration with the National Board. This may also be used for unique vessel designs. This process allows the vessel to be used in Minnesota if approved by the chief boiler inspector.

Consider this process the same as the construction of a new vessel. If a code requirement must be addressed for a new vessel then it must be addressed for a Minnesota special boiler.

  1. ASME Construction Code

    1. Use the latest edition adopted by the state of Minnesota

    2. Use the proper Section of the Code

      1. Section I (Power Boilers)

      2. Section IV (Heating Boilers)

      3. Section VIII (Unfired pressure vessels)

  2. Hold Points that a State inspector may set (This is not meant to be an all inclusive list).

    1. Confirmation of material (As addressed by the Code)

      1. Through stamping found on material

      2. Through use of Metal analyzer

    2. Drawings (As addressed by the Code)

      1. Material thickness (all parts)

      2. Dimensions (will vary with type of vessel)

        1. Overall

        2. Openings

        3. Attachments

        4. Type of heads

        5. Nozzles

        6. Manways/handholes

        7. Weld sizes

    3. calculations (As addressed by the Code)

      1. All required by the Code

    4. Other Code requirements

    5. Pressure Test (As addressed by the Code)

      1. Witness hydrostatic test.

    6. Assign Minnesota Special number

    7. Witness attachment of data plate


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