Compressor Cylinder and Casing Restoration

The challenge

A reciprocating compressor cylinder and casing corroded in the water-jacket passages and along the gasket land, so the joint weeped and the casing face would no longer seal. The cooling water found its way through the pitted passage to the joint, and the damaged sealing surface meant the casing would not pull up tight no matter how the bolts were torqued. Once a casting weeps at the joint like this, the compressor cannot hold cooling water or run reliably, and the usual fix is a replacement casing on a long lead time at a high cost.

Our approach

We take the cylinder and casing down and look at where the metal has been lost. We blast the corroded jacket passage and the gasket land back to clean, profiled metal so everything we apply bonds to bare steel. Then we rebuild the pitted casting and the damaged sealing face with a machinable Belzona 1000 Series composite and dress the land flat so the joint pulls up tight. We coat the jacket passage against the cooling water to seal the weep and protect the casting, so the compressor goes back together on the original casing.

1. Assess and mapWe strip the casing down and map the corroded jacket passages, the pitting in the casting, and the damage along the gasket land.
2. Blast to clean metalWe grit-blast the jacket passage and the gasket land back to clean, profiled metal so the composite and the coating bond to bare steel.
3. Rebuild the castingWe rebuild the pitted casting and the damaged sealing face with a machinable Belzona 1000 Series composite, working cold so the casing sees no heat distortion.
4. Reform and sealWe dress the gasket land flat so the joint pulls up tight, then coat the jacket passage with a Belzona 1100 Series material to seal the weep and protect the casting against the cooling water.
5. Reassemble and return to serviceWe check the reformed land and the coated passage and hand the compressor back to be reassembled on its original casing.