Size, Pressure & Special Routing · Size, Pressure & Special Routing

High-pressure rectangular duct

Supply/process

ConnectionHigh-pressure TDC/angle/welded
SupportEngineered supports

Before you start

  • Confirm pressure class, gauge, seam, reinforcement, joint system, gasket or sealant, fastener pattern, support design, and test requirements.
  • Inspect every section for correct construction and complete reinforcement.
  • Separate high-pressure components from ordinary low-pressure parts.
  • Verify the project-specific sealing and testing plan.

Tools and materials

High-pressure rectangular duct, approved high-pressure TDC, angle, or welded joint components, specified gasket and sealant, reinforcement and tie rods, engineered supports, clamps, drift pins, approved fasteners, and test equipment.

Lay it out

  1. Mark support and joint locations.
  2. Keep test access available.
  3. Coordinate reinforcement and fitting orientation.

Set and support it

  1. Install engineered supports.
  2. Support sections independently during fit-up.
  3. Keep joints unloaded.

Make the connection

  1. 1

    Verify construction against the pressure class.

  2. 2

    Install the specified gasket.

  3. 3

    Align and clamp the joint.

  4. 4

    Install every required corner, cleat, bolt, fastener, tie rod, and reinforcement piece.

  5. 5

    Seal seams and joints as specified.

  6. 6

    Inspect before concealment.

  7. 7

    Complete required pressure testing.

Check the install

  • Construction matches the pressure class.
  • Every joint component is installed.
  • Reinforcement is complete.
  • Seams and joints are sealed.
  • Testing meets the approved requirement.

Common mistakes

  • Using low-pressure hardware on a high-pressure system.
  • Skipping a cleat, bolt, or tie rod.
  • Covering the run before testing.
  • Using sealant to compensate for incomplete mechanical connection.

Stop and ask

Stop if gauge, seam, reinforcement, joint, support, or sealing does not match the approved pressure class.