July 29, 2024 •AMPP
On May 8, 2024, the historic ship known as the Belem navigated into the bustling port city of Marseille, France. This marked the arrival of the Olympic torch in France, where it is stationed this summer for the 2024 Olympics.
More than 150,000 spectators gathered to witness as the ship sailed into the bay, accompanied by over 1,000 boats. But without help from coatings and composites, the spectacle might not have been possible.
Alliatech, one of the French distributors of composite repair materials and protective coatings supplier Belzona, became involved in the Belem’s restoration during 2023.
Historic Facts
Considered to be the last great French merchant ship, the Belem is an impressive three-mast vessel reaching 34 meters (112 feet) tall and 58 meters (90 feet) long. She made her maiden voyage as a cargo ship in 1896, transporting sugar from the West Indies — as well as cocoa and coffee from Brazil and French Guiana — to France.
Today, blending tradition with modern features, it possesses an impressive 22 sails with a huge surface area of 1,200 m2 (12,917 square feet), along with two 575-hp (429 kW) diesel engines.
Carrying the Olympic flame is not the first time the Belem dealt with a fire on board. The ship caught ablaze during its maiden voyage — the same year the Olympic games were revived — on its way to Belem, a Brazilian port city and the ship’s namesake.
Fortunately, it was repaired and able to continue its visit, and a similar theme held true prior to this year’s voyage.
Corrosion Concerns
After all those decades of service, the propeller shaft on this 19th century naval ship was severely damaged while suffering from heavy corrosion and pitting. But given the vessel’s historical significance, the owner was keen to preserve the shaft.
Replacing it would be extremely costly, and they were understandably reluctant to lose a piece of the original vessel. With that in mind, it was vital that any potential solution could reconstruct the shaft’s damaged areas while protecting it from future seawater corrosion.
Alliatech, a Belzona-authorized distributor with more than 40 years of experience, was chosen to carry out the repair. As part of the ship’s extensive restorations prior to its Olympic voyage, the application took place while the Belem was in dry dock at the Saint-Nazaire shipyards in France.
Surface preparation consisted of grit blasting all application surfaces to achieve a 3–4 mil (76.2–101.6 micron) profile. This was done to meet the NACE No. 2/Society for Protective Coatings (SSPC) Surface Preparation (SP) 10 standard for a “Near-White Metal Blast Cleaning.” Subsequently, all surfaces were salt washed.
Once prepped, the damaged propeller shaft was to be reconstructed back to its original profile. Belzona 1111 (Super Metal), a repair composite for metal repair and resurfacing, was chosen for the rebuilding process and applied using a spatula.
A two-part repair composite for metal repair and resurfacing, Belzona 1111 is based on a solvent-free epoxy resin reinforced with silicon steel alloy. The two-part epoxy sets up quickly, so all coating is mixed at the site. The coating, which fills small holes and pits while reinforcing weak metal, comes with a specialized plastic application device with one flat side like a scraper or squeegee, and the other side featuring different configurations for different substrates.
Two coats of Belzona 5821 were then brush applied to protect the shaft from future corrosion. This product was specially designed to offer long-term protection from erosion and corrosion under immersion service, thereby providing a strong defense against the effects of salt water.
As an epoxy-based, ceramic-filled, solvent-free technology, the two-part coating can be applied using a wide variety of application tools, and each coat is designed to be put down at approximately 10 mils (254.0 microns) of dry film thickness (DFT).
Ultimately, the application of these products allowed the original 127-year-old shaft to be retained. This avoided any costly replacement, and it maintained a piece of history.
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2024 Journey
This year, once the Olympic flame was lit in Athens on April 27, 2024, the restored Belem ship began its 2,000-km (1,243 mile) journey from the port of Piraeus to Marseille.
During that time, the Olympic flame was watched 24 hours a day to ensure it stayed lit until it reached the French coast, 12 days later. A celebratory event anticipating the arrival of the ship in France featured 800 luminous drones forming a torch in the air, followed by a pyrotechnic show.
“It is fantastic to see Belzona make history on board the Belem,” said Frédéric Harle, director at Alliatech. “The customer was extremely happy with the result of the application, and it is excellent for Alliatech to have contributed to the journey of the Olympic flame for the 2024 Paris Olympics.”
As the vessel docked, and with over 100,000 spectators lining the streets of Marseilles, an Air Force flyover featured planes drawing the Olympic ring and the colors of the French flag. And thanks in part to its rebuilt propeller shaft, the Belem looks ready for its time in the spotlight.
Editor’s note: This article By Ben DuBose, first appeared on coatingspromag.com on July 2, 2024. Reprinted with permission.