Case story


Steel plant


ADB13_2011 (AD 2000)

Belman has designed and manufactured one Hinged Expansion Joint and two Gimbal Expansion Joints for a three-dimensional system in the cold blast piping at a blast furnace in a German steel plant.


The steel plant has several cold blast pipelines. The client had received a similar design solution, engineered and delivered by Belman, back in 2021, which they were very happy with. It therefore made sense for the client to place an order for the same design solution for another cold blast piping in their steel plant. The first order was engineered by Belman according to the needs and requests of the client in order to optimally accommodate movements. The design of the steel plant’s pipeline, which works as a three-dimensional system, originally had two sets of two Hinged Expansion Joints built together to work as a Gimbal Expansion Joint in the vertical pipe and a Tied Expansion Joint in the horizontal pipe. Belman optimised that solution by engineering two Gimbal Expansion Joints and one Hinged Expansion Joint. The solution works so well for the steel plant that they wanted the same design for another pipeline.



Two Gimbals and one Hinged Expansion Joint for a three-dimensional system

Based on this request, Belman once again designed two Gimbal Expansion Joints for the vertical pipe and one Hinged Expansion Joint for installation in the horizontal pipe. In this way, the steel plant achieves optimal accommodation of movement by utilising its piping layout as a three-dimensional system (see the drawing of this system on page 73 in the Expansion Joint Catalogue). This three-dimensional system is a viable solution that is often used when you have a pipe going in a vertical direction that changes into a horizontal direction. The three-dimensional system absorbs movement from the horizontal pipe in any direction through the use of the gimbals, while the Hinged Expansion Joint takes the vertical movement resulting from the reduction of the vertical distance between the gimbals. The three-dimensional system also works in systems with inclining or declining piping. As the horizontal pipe expands and generates axial movement by pushing at the corners, the hinges on the Hinged Expansion Joint prevent it from compressing or expanding in the longitudinal direction if it is affected by the load of the piping. This thus fixes an issue that caused problems for the old solution, ensuring optimum movement absorption and improving performance and service life.

The original solution was to have 2 x 3 bellow convolutions, which Belman was able, via the Gimbal design, to change to seven bellow convolutions. Despite adding another convolution, this design optimises plant operations by reducing both building length and overall weight.

The load of the pipe is carried in the guides and supports (spring hangers, constant hangers etc.) placed along the pipeline. While the Expansion Joint design brings stability to the pipeline, it cannot completely eliminate the need for guides and supports.


Expansion Joints according to ADB13_2011

As per the client’s requirements, the Expansion Joints were designed according to ADB13_2011. This very strict German AD 2000 design code is widely used for components designed and manufactured for steel plants in Germany and was requested by the client. Belman has extensive experience with Expansion Joints built according to this design code.


Belman – expertise in Expansion Joints for steel plants

Belman has extensive and far-reaching expertise in the design and manufacture of Expansion Joints for steel plants, both in Germany and worldwide. Belman has an unusually long reference list for this industry and can custom-design Expansion Joint Solutions, including Expansion Joints with refractory lining, brick-lining, with a manhole, gimbal design, hinged design and tied design. The company has even supplied an Expansion Joint weighing in at 40 tonnes. This is why steel plants have been returning to Belman for their Expansion Joint solutions since 1994.