ABB Azipod® propulsion systems placed below an icebreaker’s hull can push through the thickest ice. Citec designed heavy-duty production devices for this heavy-duty product’s whole chain of production. They are strong enough to safely lift and transport propulsors of up to 70 tonnes.
The design of production devices
Citec designs complete processes in-house from start to finish, which is why we can make projects proceed as easily as possible for the customer. Citec develops production tooling from the concept to final planning and the documents required, according to the customer’s needs.
When necessary, we also perform the preliminary analysis of manufacture, such as inviting tenders for the manufacturing processes. Citec observes standards and keeps up-to-date on changes in government regulations on behalf of customers.
The gearless and steerable ABB Azipod(R) thruster is the world’s leading propulsion system for icebreaking vessels. The electric drive motor is in a submerged pod outside the ship’s hull. Azipod propulsion units obviously meet massive ice loads in the freezing water, so the conditions place heavy demands on them. They have to be large, durable and strong.
“Our largest Azipod propulsion model weighs 70 tonnes and is 5 metres long”, says Juha Korhonen, Business Unit Manager at ABB.
There are always many issues to be solved when manufacturing and transporting massive products. ABB has been leading the ice propulsion market for 75 years and has long been supplying the market with different kinds of Azipod propulsion units. But when the company was planning the production of the Azipod ICE 1400 propulsor, it faced some completely new challenges: there were no devices of the same size with as strong an ice class as this model’s, so the company had to develop the production devices for it from scratch.
“Just then Citec happened to inquire if we needed any kind of design help. Because Azipod propulsion units are so large in themselves, so is the production tooling required. They both have to be handled with cranes in the assembly hall”, Korhonen explains.
ABB has long been Citec’s key customer in many sectors except propulsion. Now Arto Rajanen, Head of Product Engineering at Citec, was taken onto the floor of ABB’s assembly hall next to an Azipod propulsion unit and was asked if Citec would be interested in making the production devices for it. Rajanen said yes, and the cooperation began. Citec was tasked with designing the production tooling for the Azipod ICE 1400 propulsion system’s whole chain of production. These devices include the tools needed to handle the product, production and testing equipment, lifting gear and transport and handling equipment.
Regulatory requirements on the production safety have become increasingly stricter, and Korhonen remarks that safety is the number one value also for ABB.
“Citec designed the CE-marked tools, with every necessary strength calculation and risk assessment performed on them. Also, the lifting plan for the Azipod propulsion units in the factory and the transport plan for land and sea routes were important. For example, the transport frame has to function in such a way that the gigantic propulsor will not fall over during transportation even in very rough seas”, says Kim Edsvik, Project Manager at Citec.
The project proceeded smoothly. Because there were a lot of government regulations to take into account, the compact planning team worked efficiently and in close cooperation with customers to ensure the best possible result. For Citec, the project was particularly interesting, because this was the first time it was producing production tooling on such a large scale.
“We got to consolidate the whole chain of production and participate in the planning of the product’s manufacturing process, transport and regulatory planning”, says Rajanen.
ABB sought out Citec as their cooperation partner because they were convinced by Citec’s previous references and solid expertise.
“Of course, there are some challenges with every project. The true indicator, however, is the way they react. Citec always did a perfect job”, Korhonen praises.
The two companies’ continued cooperation is another sign of customer satisfaction. Since then Korhonen has transferred to ABB’s factory in China and still orders production tooling from Citec, now for the Azipod thruster models manufactured there.