On an LPG ship, there was a large titanium heat exchanger which broke down.
Liquid gas with a temperature of-40 degrees flows through the outer tube, seawater pumped through the small tubes become allowing the gas to heat up.
To guarantee a long life, it is made entirely of titanium.
By stopping pumping sea water into the small tubes, water that was still inside froze and as we all know, water expands when it freezes. The result, 65 of the 800 tubes leak.
Our help was invoked because we are the specialist in (titanium) welding.
Welding of titanium occurs mostly in one of our purge chambers, but on location, it is always a challenge to keep enough inert gas around the welding.
We have welded the leaky tubes of the titanium heat exchanger completely shut with solid titanium plugs.
After welding, there is a independent penetrant research carried out and the results were 100% positive, as we expected.
More info about titanium/purge chamber welding can be found here