The London and North Western Railway (LNWR) Webb Coal Tank is a class of 0-6-2T steam locomotive. They were called "Coal Tanks" because they were a side tank version of Webb's standard ‘17-inch’ Coal Engine, an 0-6-0 tender engine for slow freight trains – the term ’17-inch’ referring to their cylinder diameter.
The design was introduced in 1881 by F.W. Webb and had the same cheaply produced cast-iron wheels and H-section spokes as the tender engines. A trailing radial truck supporting the bunker was added also with two similarly cast-iron wheels. Three hundred were built between 1881 and 1897.
At the 1923 grouping, 292 passed to the London Midland and Scottish Railway (LMS). They were renumbered from the LNWR's random allocation based on vacant numbers, to a solid block sequence 7550–7841, and given the power classification 1F. Many locomotives still in service in 1934 were renumbered by the addition of 20,000 to their number.
Sixty-four locomotives passed into British Railways ownership in January 1948 and they were numbered 58880–58937, but not all examples survived long enough to carry their BR numbers. One example is preserved.