Wellhead Flange Face Reforming

The challenge

A wellhead flange face corrodes and pits where the gasket seats, and once the sealing surface loses its flat, continuous profile the gasket no longer makes up tight. Product weeps past the joint, the connection cannot be trusted to hold, and the usual fix is to cut the flange out and weld in a replacement. That means hot work on a live tie-in and pulling the spool, which is costly, slow, and disruptive to keep the wellhead in service. The owner needed the face back to a sound sealing surface without taking the spool out.

Our approach

We work the flange in place. First we machine the face clean to take off the corrosion product and open up the bottom of the pits so the repair has sound metal to key into. Then we cold-rebuild the face with a Belzona 1000 Series metal-repair composite, filling the pitting and the lost profile back up. We bring the rebuilt face down to a flat, even sealing surface that matches the gasket footprint, working cold so there is no hot work and no distortion of the spool. The gasket seats on a continuous surface again, and the joint makes up and holds.

1. Assess the faceWe inspect the flange face to map the pitting and the corroded, low areas across the gasket seating surface.
2. Machine cleanWe machine the face clean to remove corrosion product and open the pits down to sound metal so the rebuild keys in.
3. Cold-rebuild the faceWe fill the pitting and lost profile with a Belzona 1000 Series composite, working cold with no hot work and no spool removal.
4. Reform to a sealing profileWe bring the rebuilt material down to a flat, even sealing surface that matches the gasket footprint.
5. Make up and return to serviceWe confirm the face is sound, the gasket is made up against a continuous surface, and the wellhead goes back into service.