Project DA – From Heavy Metal to Cleaner Air: LEV evolution at the historic Salisbury Site

At the heart of Birmingham’s industrial sprawl, a few minutes' walk from the legendary Villa Park stadium, where Black Sabbath recently played their final thunderous note in July, stands a lesser-known but equally resonant site of metalcraft and power making new vehicle axles.

Formerly known as Salisbury Axles, the facility once manufactured components for the British car industry including iconic models such as Aston Martin’s early DB car, a hallmark of British automotive engineering.

Historic Salisbury Transmission advert for Aston Martin DB2 & DB3 (circa 1952)

Today, that same site has transformed into a modern production hub, housing robotic welding booths and a forward-thinking approach to workplace safety and environmental control.

This case study tells the story of how three cartridge filters, installed as part of a custom-designed Local Exhaust Ventilation (LEV) system, now manage the air quality across three robot welding cells— protecting the workforce while respecting the legacy of Birmingham’s iron and fire past. Along the way, we draw parallels between heavy industry and heavy metal, exploring how echoes of the past continue to shape the city’s future.

Birmingham has long been Britain’s beating industrial heart. This factory that now supplies vehicle components to British and European manufacturers was once home to Salisbury Transmissions, later Salisbury Axles — a cornerstone of the UK’s post-war automotive revival. Among its most famous clients was Aston Martin, which sourced components from the site for its DB2 line in the early 1950s. These vehicles blended luxury and power, and the axles beneath them carried the force of an industry rebuilding itself from wartime ashes.

Now acquired by our client, a global leader in drivetrain and e-propulsion systems, the plant now serves the ever-evolving needs of the automotive sector — a technically advanced company, where robotic welding machines on the shopfloor ensure the highest possible standards are met each and every time.

Robotic welding might seem cleaner than manual welding, but the reality is different. Despite the precision of machines, the chemical byproducts remain the same — manganese, chromium, iron oxide, and nitrogen oxides hang in the air long after the arc is extinguished.

Left unchecked, these fumes pose severe risks to both health and equipment. The HSE (Health and Safety Executive) mandates strict control of such airborne contaminants. In 2024, the client committed to investing in a custom-designed LEV system to manage emissions from three of their busiest robotic welding booths

The solution comprised three high-capacity CleanPULSE cartridge filter units, each serving a separate robotic welding booth. Each filter unit was specified with self-cleaning filter cartridges, high-efficiency fans, and VSDs to modulate extraction.

Screenshots of our 3D design, using measurements taken on site for location of the filters.

Design Considerations

Key design challenges included:

• High Extraction Demand: Robotic welders operate in bursts but generate significant fume loads. Each booth required a robust extraction setup capable of handling peak volume.
• Accessibility and Maintenance: The system needed to be easy to service without disrupting production.
• Modularity: Future expansion was inevitable — the system had to be scalable.
• Aesthetic Integration: Though secondary, management also wanted a system that reflected the site’s commitment to modernisation.

The LEV Solution – Three Cartridge Filters, One Clean Future

System Overview

The final solution comprised three high-capacity cartridge filter units, each serving a separate robotic welding booth. Each filter unit was specified with:

• Self-cleaning filter cartridges with pulse-jet technology to maintain pressure drop and extend filter life.
• High-efficiency fans, mounted on vibration-dampened skids, rated for continuous operation at over 95% efficiency.
• Variable Speed Drives (VSDs) to modulate extraction rates based on welding activity, conserving energy during idle periods.

Ductwork and Controls

A network of galvanised steel ducting, with flexible hose drops into each robotic cell, connected the booths to their respective extraction units. The controls featured:

• Automated start/stop, triggered by welding activity.
• Local fault indicators at each booth.
• A central control panel for facility management, allowing live system monitoring and logging.

Installation and Commissioning

Installation was carried out in two phases over three weeks to minimise downtime. Pre-commissioning checks included:

• Airflow measurement at source hoods.
• System balancing.

Birmingham isn’t just known for making metal — it invented heavy metal. In July this year, just around the corner from this factory, so close to where (the late) Ozzy Osbourne grew up and with his band Black Sabbath, took his final bow at Villa Park such a short time before his recent sad passing. The band’s music was forged in the same crucible as the city's industry, their sound mirroring the thunder of forges and the daily grit of Birmingham’s workers.

Employees note that while the plant now operates with robotic precision, it echoes the spirit of the city’s industrial and musical past (though not too loudly, thanks to the ducted sound attenuators we included in the outlet ducts off each fan). The LEV system represents progress: a modern response to old risks — one that puts people and the planet first.

Investment in LEV technology isn’t just about keeping the workplace tidier it’s a legal requirement for compliance —A statement that a site steeped in the glory of British automotive history can also stand at the cutting edge of a modern workplace.

Just as the Aston Martin DB2 represented a leap into the future, so too does this modernised welding line. The cartridge filters don’t just extract fumes — they extract a cleaner, safer, more responsible future for the employees. Below is our smoke capture test.

This LEV project is a blueprint for how old industrial sites can rise to new challenges — not by abandoning their past, but by building on it. Just as Sabbath closed their final concert a few hundred metres away, the last chords of yesterday’s industry are giving way to a new kind of power: cleaner, smarter, and no less mighty.

In the end, whether it’s an axle or an anthem, Birmingham still knows how to deliver heavy metal.