Rail crossings are made of cast steel, alloyed with manganese, and are then welded to lengths of rail track.
Then the casting surfaces are ‘explosively depth hardened’ to ensure that the surface is hard wearing so the crossings can withstand trains wheels running over them.
Progress Rail in South Queensferry is a world leading company that makes these for the global rail industry.
The hub of a wind turbine is made of ductile cast iron as it is strong and can withstand the forces imposed by the weight of the blades.
These hubs can weigh several tonnes.
The quality and integrity of the castings is very important.
Picture credit: C Creative Commons Zero (CC0) Wind Turbine Hub dreamstime 93949503
Manholes covers might not seem to be very exciting perhaps, but they need to be strong so that they can be run over by lorries again and again, without failing so are made to exacting standards.
Can you imagine the traffic jams if they kept failing?
Some countries have very decorative manhole covers, like this example from Norway.
Manhole covers are made of cast iron, using sand casting.
The blades in a jet engine are made using investment casting.
They are cast in exotic alloys, sometimes as single-crystal structures, so that they can withstand the temperatures and pressures in a modern jet engine. The quality and integrity of the castings is very important.
Rolls-Royce recently built a new, highly automated foundry in the UK capable of producing 100,000 cast blades per year in the UK.
These street bollards are cast in manganese steel and are built to last – they are used to protect buildings and city squares from ram raiders – a great example of castings being used to protect us in our everyday lives.
If you have been fortunate enough to travel on an aeroplane, then you will have sat on a seat like this.
You may not have noted the seat base below you which is a casting.
Aircraft seat bases are cast in aluminium which is strong and light. Low pressure die casting is the process that is normally used to produce the parts.
Car wheels are cast in aluminium which is strong and light. Low pressure die casting is the process that is normally used, and millions of die cast wheels are made every year.
You can also see a brake disc here, which is also a casting – this disc is made by pouring molten grey cast iron into a sand mould. Highly automated, high volume greensand casting is the process used and the sand for the mould is used over and over again. Castings are used to keep us safe on the roads.
You might also be able to spot the brake caliper which is also an iron casting. Castings are everywhere!
