| Driving Wheels | 6ft 2ins |
| Weight | 140 tons |
| Boiler Pressure | 180psi Superheated |
| Cylinders | Outside – 21½in x 28in |
| Tractive Effort | 26,760 lbf |
| Valve Gear | Walschaerts |
99 Indian Railways class XB locomotives were built between 1927 and 1936.
- 83 by Vulcan Foundry
- 12 by Armstrong Whitworth
- 4 by North British Locomotive Company
The locomotive was built with the help of British Engineering Standards Association (BESA).
It was up to date as any locomotive in England but had a lot of problems. They still proved to be successful as they survived till the 1980s.
The locomotives had American 3-point suspension with compensating levers for indifferent tracks in India.
Like other X series 4-6-2 locomotives they were prone to frame fractures. One unit had 9 fractures in 9 years. During an eight year period, 18 of the East Indian Railway Company (EIR) XB class locomotives spent three years in a repair shop.
Other problems encountered included chronic problems with the coupling rods and the boiler.
The worst fault of the locomotives was there tendency to hunt or oscillate laterally, i.e., at right angles to the track causing the track to distort. This caused the locomotives to have a tendency to derail.
In July 1937 107 people died when one of the locomotives jumped the track and derailed near Bihta whilst travelling at 60mph when hauling the Punjab Express.
Following an inquiry into the cause of the accident it was recommended that the leading and trailing bogies should be fitted with stiffer side springs and better damping.
This proved to be a success and the recommendation was implemented by The Bombay, Baroda and Central India Railway and Madras and Southern Mahratta Railway. The locomotives were also restricted to slow-speed trains. No further derailments were reported.
It is interesting to note that the recommendations also proved useful in improving some locomotives on the LMS in Britain which had similar but less severe problems with lateral movement.
All of the class XB locomotives were scrapped in 1983 apart from one which has survived in Pakistan.
Preservation
Builder unknown EBR 450
This locomotive was built in Britain for Indian Railways at some time between 1927 and 1936.
It is preserved in Pakistan at Lahore workshops.
served Outside Britain – By Country
Preserved British Steam Locomotives 