The rail industry is, like many sectors, continually looking for more efficient, effective and commercially viable ways of operating. As a result, a process which is becoming much more widespread is the galvanizing of steel. Steel is a vital raw material used across the industry, from network infrastructure to smaller assets including safety fencing and signage. So, what is galvanizing, what is the technology behind it, and what projects within the industry is the process being used on?
Hot-dip galvanizing involves steel being cleaned and then dipped into molten zinc at temperatures up to 450oC, where a series of zinc-iron layers are formed by a metallurgical reaction between the iron and zinc creating a long- lasting, durable coating. Because it forms alloy layers with the iron in the steel it is much more robust than other coatings which only bond chemically or mechanically and can easily be damaged.
Galvanizing really comes into its own when it comes to sustainability, with a single treatment able to coat a product inside and out, as well as being able to protect steel for up to 60 years, or longer if the conditions are right.
Even in the harshest of environments, it can last two or three decades. As a result, the whole life costs of products protected by hot-dip galvanizing can be significantly reduced because there is no need for expensive down-time and the inconvenience of repeated on-site maintenance and repair,
an appealing aspect for many rail operators.
Galvanized in Manchester
To showcase the real value of the process to the industry, Manchester Galvanizing, part of Wedge Group Galvanizing, regularly hosts dedicated open days for the rail sector. These provide inspectors, buyers and other core personnel the opportunity to see the galvanizing process ‘up close’, so they can
learn how galvanizing fits in with CE Marking and get best practice tips for inspection of galvanised steelwork. The Group is also proud to be an approved supplier for the Railway Industry Supplier Qualification Scheme (RISQS).
Manchester Galvanizing has been involved with a variety of rail projects, including the refurbishment of the iconic Hull and Barnsley railway bridge (pictured below) which saw them galvanize over 25 tonnes of structural steel as part of work to strengthen the bridge and ensure the track remains operational for its current capacity.
The company also did work on the grade II listed Silver Jubilee Bridge, one of the world’s longest steel arched bridges which runs over the River Mersey, connecting Runcorn to Widnes and sees 80,000 motorists a day pass over it.
Over 200 tonnes of steel was galvanized as part of the £25million project to transform Edinburgh’s Haymarket Station into a major transport link, material for the production of canopies installed above the station’s newly-extended platforms.
The C503 Crossrail Contract refurbishment works at Liverpool Street Station also saw over 100 tonnes of steel protected long term with hot dip galvanizing.