Case studies

Vortex Generator - Hammersmith

Steel Dynamics designed and manufactured the HUGE vortex generator assembly for the Hammersmith Pumping Station in London.

The giant stainless-steel vortex generator assembly was 3.6m in diameter and over 21m long and was successfully lowered into the shaft as a 'one-piece lift' operation, after significant design innovation, research and development by Steel Dynamics.

The vortex generator assembly forms the centrepiece of the work at the site as part of the super sewer project for London.

Before the project, every year around two million tonnes of sewage overflowed from the pumping station and into the River Thames. This was a huge environmental issue for the city.

The sewage system upgrade project was designed to divert the flows into a new 25km (15.5 mile) super sewer, constructed deep beneath the Thames river.

At Hammersmith, because of the terrain, the flows needed to drop down a 25-metre-deep shaft – which is why the vortex tube was needed.

The scale of the Hammersmith Vortex Generator is shown below. The generator wing plate assembly protruded 5.5m from the vortex tube centre and was 3.5m tall.

Given the physical infrastructure constraints of bridges and widths of roads, the whole assembly could not be transported from the factory and delivered to London as one-piece assembly. So it was innovatively designed as two main sub-assemblies which would be then connected (welded) onsite at ground level, before being dropped down the shaft and into the final operating position.

The photo below shows the Hammersmith vortex tube sub-assembly lying next to the generator wing plate sub-assembly, before ground level connection.

The scale of the construction is apparent as the 15m+ diameter shaft is shown to the right.

When positioned, the whole vortex generator assembly sits inside the shaft, below ground level.

The photo below shows the Hammersmith vortex tube being prepared for delivery to site.

The photo below shows the HUGE Vortex Generator wing plates arriving at the Hammersmith site for Steel Dynamics ground level connection (welding) to the generator tube.

After connection, the whole vortex generator and tube assembly is then lifted and dropped down the shaft as a one-piece construction.

This innovative design saves significant in-shaft connection of the two sub-assemblies, saving time, cost and eliminating difficult vertical welding in confined spaces and significant operator risk.

Flows, falling the 15m+ distance, would wear away the bottom of the shaft. However, the innovative 28-tonne vortex generator ‘spins’ the flows down the vortex tube, removing the flow energy and preserving the base and integrity of the system.

In the execution of the Hammersmith Vortex Generator, Steel Dynamics undertook significant 3D design and lift simulation studies supported by extensive Finite Element Analysis (FEA) and calculations verified by 3rd party chartered engineers.

The significant commercial and technical advantage of the 'one-piece lift' of the whole generator assembly into the shaft was only possible because of the extensive design, research and development work undertaken by Steel Dynamics.

In 2020 the vortex generator was rotated and dropped down into the shaft in a complex and meticulously-planned lifting operation.

The 21-metre-long, 65-tonne pipe section of the system has had over 1,000 stainless steel studs painstakingly welded onto its outer wall that slotted precisely into place during the installation.

The delivery, installation and commissioning of the incredible project was very successful and will hopefully be appreciated by all stakeholders in London over the next 120 years design life. This success story stands as a fitting tribute to the hard work and dedication of the talented team involved.