The massive roller drum gate of the regulating dam at Imatra hydropower station in Finland was coated on site using the traditional INERTA 165 epoxy coating system. It had been 30 years since the last coating of this site, which is highly challenging due to being immersed in water. Teknos coating system has survived the test of time.
The founder of Tornion KaMa-Palvelut Oy, Kari Marttila, checks the pressure and temperature of the paint and contacts the painter with a walkie-talkie. “Everything all right down there?” Kari asks and is pleased to hear an answer in the affirmative.
The conditions in Imatra are challenging, but the team has made an effort to create optimal conditions for the coating process. Under the canvas, the temperature is 23 degrees Celsius and all surfaces have been carefully cleaned after the sandblasting in preparation for the spray coating. However, the rainy summer was not favorable to the coating project.
“It rained for almost a week, so you couldn't really do anything. It's not worth risking the project because of rain,” Kari Marttila says.
From Tornio in Southern Lapland, it is almost 700 kilometers to Imatra in South-Eastern Finland. Long distances are not a problem for Tornion KaMa-Palvelut, because the company uses rolling stock. The company operates in all of the Nordic countries. Half of the work time is spent on the road.
The construction of Imatra power plant began in the 1920's and its last expansion was completed 1951. The roller drum gates of the regulating dam were last coated 30 years ago, with Teknos paints.
The painter at the other end of the walkie-talkie, Aki Marttila, comes out from the depths of the dam. Aki always knew he was going to become a painter. “I like this job,” Aki says with a smile.
Aki Marttila is pleased with Teknos coatings. The TEKNODUR COMBI 3430 polyurethane paint gets a special mention. Aki also has a lot of experience with the INERTA 165 epoxy coating.
Immersed steel surfaces, corrosivity category Im1:
INERTA 165 epoxy coating 2 x 250 µm
“The product and the equipment are good, so is the temperature. When you spray with high heat, the coating reacts fast and there won't be any borders,” Aki says about spraying the epoxy coating on the site.
“This sure is a challenging site. For example, there is a lot of angle iron. The key when painting is that you are organized and don't miss any parts. Since the surface is so old, this project has several stages,” Aki says. “On the positive side, on the back side of the gate it is smooth steel plate and the rapids have fresh water, so the plate has been easy to spray,” he adds.
“Couldn't be much smoother,” observes Pekka Virolainen from Teknos as he inspects Aki's work.
The renovation of the dams at Imatra power station began in the summer of 2015 with the building of a new spillway bridge. Last summer, the sector gate was renewed. The concrete structures of the regulating dam and the walls of the intake channel are under repair simultaneously.
“Next spring, we'll start repairing the other roller drum gate. The whole project will take four years,” says project manager Heikki Puuska, Fortum Power and Heat Oy.
The reparation of the gate, the renewal of the frames and auxiliary systems of the gate are done by OMP Konepaja Oy. “As part of the renovation, we changed the seals of the gate, both chains and heat transformers, and added air compressors,” says Matti Riekki from OMP Konepaja.
The surface treatment, including the blasting, dust removal and spraying, of one roller drum gate takes a bit more than a month. In a large-scale project, it is important that co-operation between all parties is smooth. KaMa-Palvelut praises the project management at Imatra: the main contractor has stood up to the challenge and listened to the wishes of the subcontractor.
“On this site, they listen to the needs of the subcontractor. For next year, we plan to further polish and improve our work methods," Kari Marttila says.
KaMa-Palvelut is currently building a new wet paint and powder coating paint shop in Tornio. With the new paint shop, due in 2018, the company hopes to serve its customers even better. Teknos has been involved in the construction project since the beginning.
“We aim for quality and listen to the needs of our customers. When the factory sends us new information, we spread it in the field. The service we have gotten from Teknos has been unique. Janne sure is an important asset to our company,” Kari Marttila says in praise of Jan Åkerlund from Teknos.
When Kari is asked about the strengths of KaMa-Palvelut, he thinks for a moment and then says: “We're open 24/7 to meet our customers' wishes. We're honest men who value straight talk.”
Customer: Fortum Power and Heat Oy
Main contractor: Destia Oy
Renovation of the gates: OMP Konepaja Oy
Surface contractor of gates: Tornion KaMa-Palvelut Oy
Total duration of project: 4 year
Further information: www.ka-ma.fi