Creative fixes with Belzona

Authored by: Martin Leduc, Pictures: Allan Austin

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I met Allan from Belzona, a few months ago at a meeting, it was the first time I'd met him, but by no means, is Allan new to the business. Pretty much everyone on the west coast is familiar with Allan and Belzona, because he's always bouncing around shipyards and ships. I asked him to forward me some of the repairs he's carried out, he sent the following, he writes...

I have repaired a number of pump volutes, but this was the worst I have done. It is the main cooling pump for a small coastal freighter / passenger ship. The sister ship was in dry dock and when this pump failed, quick repair was imperative. A replacement pump would take at least 6 months to have made, and at great expense.

Makes you wonder how it ran as long as it did. This is the outside of the pump volute

This pump was repaired and back in service in about 3 days, and still in service today. It will now likely outlive the ship. Before the parts where blasted we took as many dimensions as possible knowing that this pump was going to lose a very thick layer of corrosion.

Only a shadow of its former self Another piece of this badly corroded

We were able to repair the volute by gluing steel plates over the holes using Belzona� repair compounds, and then filling the voids to bring the pump back to its original dimensions. Some parts of this pump were formed in place to restore complex profiles. The entire inside of this pump was coated in Belzona� products isolating the cooling water from the metal to provide a long service life for this old pump.

Plates glued over holes. Jacking bolts were removed later Jigs were used to maintain accuracy for seals and bearings.


Another job we did at Alberni Engineering in Port Alberni. Battery acid had leaked onto the hull of the vessel eventually eating through the ferrocement and steel mesh, causing the hull to leak.

Damaged hull was repaired using some new steel mesh, and Belzona 4111. Missing is a picture of the "faired in" outside finish.

The yard had just finished this repair and left the vessel tied to their dock, and when they came back after the weekend found the boat had been rammed.

Below, are of boat after what happened on the weekend, and the subsequent repair of the damages. As can be seen in the pictures the vessel was holed through when it was rammed by another vessel.

Again the repair was accomplished using Belzona 4111 to repair the damaged ferrocement. There was also a fair amount of damage to the interior of the vessel that also had to be repaired after the hull was repaired.

Before and after pictures

Allan also has a blog on repairs, Repairtech. You can find out more about Belzona, by visiting their websites BelzonaBC and the marine area on Belzona, or you can reach Allan directly at ...

Allan Austin
Technical Consultant
Belzona Molecular (B.C.) Ltd.
Cell: 250 755 6852

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