Since the 1870s, tank wagons have been used to transport liquid products in bulk. Ever since then, virtually all tank wagons have been owned by the chemical companies or private leasing agencies rather than by the railways themselves. Because of commercial pressures to ensure speedy and safe delivery, privately owned tank wagons have generally kept up with wagon design improvements, so as to enable fast running.
They are divided into Class A (highly flammable liquids) and Class B (less flammable liquids - oil, paraffin, etc.). From the earliest times - in case of leakage - bottom valves for gravity discharge have been permissible only on Class B wagons. For most of the 20th century, Class A tankers were painted silver or light grey.
|78||Rect. Tank Wagon, Scottish Tar Distillers, Falkirk||1877||Cowlairs|
|13||10 ton Tank Wagon, Oakbank Oil Company||1894||Pickering|
|A43||Tank Wagon, Shell BP||1897|
|161||14 ton Tank Wagon, Naval Store||1918||Hurst Nelson|
|20||14 ton Tank Wagon, Briggs, Dundee||1918||Hurst Nelson|
|17||14 ton Tank Wagon, Briggs, Dundee||1927||Roberts|
|206||20 ton Tank Wagon, BP||1930||Met.Cam.|
|241||20 ton Tank Wagon, BP||1940||Standard|
|4||20 ton Tank Wagon, BP||1941||Hurst Nelson|
|14||14 ton Acid Tank Wagon, Ministry of Supply||1941||Hurst Nelson|
|252||20 ton Tank Wagon, BP||1951||Grazebrook|
|261||20 ton Tank Wagon, BP||1956||Hurst Nelson|
|BPO67496||45 ton TTA Tank Wagon, BP||1966||Pickering|