Full Steam Ahead with the A1 Steam Locomotive Trust

As part of a continued collaboration between Brooks Forgings (Brooks) and our sister company W.H.Tildesley (WHT), we have once again successfully manufactured and supplied a number of forged components known as foundation ring corner blocks to the A1 Steam Locomotive Trust.

The team at the A1 Steam Locomotive Trust is responsible for the overall funding, overhaul, servicing, and management of several steam-driven locomotives including the A1 class No. 60163 Tornado and P2 class No. 2007 Prince of Wales.  Over time, they have identified weaknesses in the original boiler design and construction that have led to more frequent periods of ‘off the rail’ downtime due to essential repair.

drop forged boiler foundation ring corner block

forged boiler foundation ring corner blocks cooling

Since 2014, both Brooks and WHT have played a vital part in overcoming the weaknesses by offering a forged solution. During service life, a fully machined corner block with exposed and uncompressed grain flow would start fracturing between 18 and 24 months after commission. A forged variant with fully aligned and compressed grain flow lasts between 42 and 48 months before showing signs of failure, ultimately saving the trust money and resources.

In modern-day scenarios, steam locomotives are put through a much harsher operation regime, and this leads to a higher frequency of thermal cycles. In the case of Tornado, the boiler would see between 20 and 30 thermal cycles each day of operation.  The thermal expansion stresses involved, unavoidable by design, are channeled towards the foundation ring corners and ultimately fracture as a result. More detailed information can also be found on the A1 Steam website by clicking the following link: https://www.a1steam.com/tornado/news/tornado-details/forging-not-cutting-corners

The manipulation of the material grain flow is critical to the success of the project, and this is achieved through two key processes. Firstly, Brooks hot bend the raw material, P265GH boilerplate, measuring 115MM X 120MM X 536MM and weighing 60KG each.

raw material boiler foundation ring corner block

raw material bending process forged boiler foundation ring corner block

The longitudinal grain flow, as shown in the illustration below, now flows around the bend. This creates what is known as a forged preform. The second process, drop forging, is performed by WHT. The preformed material is heated and placed into forging dies that contain the impression of the final desired shape. The material is manipulated through a series of controlled blows, both compressing and aligning the grain flow to give the component its strength and resilience. This can be observed in our illustrations below.

MACHINED grain flow study of foundation corner block

FORGED grain flow study of foundation corner block

Once the forgings are complete they are dimensionally checked and shot blast in preparation for final packing and shipping to the project. Once received, they are machined to match the specific foundation ring in production and then welded in place.

forged boiler foundation ring corner blocks shotblast

forged boiler foundation ring corner block machined in situ

Both Brooks and WHT are proud to be involved in keeping these steam-powered giants on track for future generations to enjoy. If you have a similar project or require the production of forged components please get in touch with us to discuss your exact requirements.

Photo Credit, Top Banner, Tornado 60163 Photo Taken by Alan Wilson : Alan Wilson Flickr