Belman’s 40t expansion joints were manufactured in 2007 and are operating successfully in the blast furnace of a German steel facility.
The expansion joint still holds the record of being the heaviest expansion joint ever made at Belman. Since then, we have expertly designed, manufactured and arranged transportation for numerous heavy and big dimension expansion joints. However, since this project, Belman has never surpassed its record of 40t. Because of its size and weight, this expansion joint was dispatched with special transport, including a police escort and a carefully planned route to the steel plant.
A total of 60t of expansion joints were actually delivered
The 40t heavy expansion joint, which is almost 10 meters long and 2,8 meter in diameter, was delivered together with an additional expansion joint. This was another heavyweight, weighing in at 20t with a length of 3.5m and a diameter of 2.8m. It was installed at a height of 100m at the steel plant due to its required location in a fall-pipe. When the iron is melted in the blast furnace different mixes of gases and emissions are released amongst the blast furnace gas. This 300°C hot gas is purified in a special decontamination unit, which is installed in the blast furnace system.
Optimised movement absorption ensures stability with two expansion joints working as one
Installing an expansion joint in a pipeline entails cutting the pipeline and in doing so multiple forces are released. In this case, 250t of forces are released. Further, the height in itself limited the options for fixing the expansion joint – therefore a customised solution was required.
The solution for the optimised absorption of movements was provided by a single angular expansion joint and one universal expansion joint with hinges, working together as a double angular expansion joint. The expansion joints were placed in a change of direction in the run of the pipeline and installed as a three-hinge system. In this way, the optimal absorption of the two plane movements is delivered. The hinges ensure that the expansion joints and the movements are guided and resist the influence of wind and momentum. Finally, yet critically important, these hinges bring stability into the pipeline and contribute positively to the challenges with limited options for fixation.
Special requirements for the 40t and 20t expansion joint
The bellows of both expansion joints are made of the corrosion-resistant material Inconel 625. The media contains abrasive particles, in order to combat this the inner sleeve is made from Hardox 400 abrasion-resistant steel. Welding ends, intermediate pipe and hinges are made from P355NH high-strength steel which is also resistant towards high temperatures. These materials were specified as a necessary requirement from the customer.
Many large sizes and heavy expansion joints delivered since this project
Belman has expertly designed, manufactured and supplied many large sizes and heavy expansion joints for steel plants and also for other industries. This includes the complicated FCC expansion joints for oil refineries, DN 4200 diameter expansion joints for pulp and power plants and large corner relief expansion joints and pressure balanced expansion joint for fertilizer, power plants amongst many others.