| British Rail Class 231 FLIRT | |
|---|---|
 Class 231 unit atLisvane and Thornhill in 2023 | |
.JPG) Interior | |
| In service | 18 January 2023 – present[1] |
| Manufacturer | Stadler Rail |
| Assembly | Stadler Bussnang AG |
| Built at |
|
| Family name | FLIRT |
| Replaced | |
| Constructed | 2021–2022 |
| Number built | 11 |
| Number in service | 11 |
| Formation | 4 cars per unit:[note 1] DMS-TS-PP-TSW-DMS[2] |
| Fleet numbers | 231001–231011 |
| Capacity | 170 seats,plus 36 tip-up & 180 standees |
| Owners | SMBC Leasing[3] andEquitix[4] |
| Operators | Transport for Wales Rail |
| Depots | Canton (Cardiff) |
| Specifications | |
| Car body construction | Aluminium |
| Train length | 80.7 m (264 ft 9 in) |
| Width |
|
| Height | 3.915 m (12 ft 10.1 in) |
| Floor height | 960 mm (3 ft 2 in) |
| Doors | Double-leaf sliding plug,each 1.300 m (4 ft 3.2 in) wide (total 6 per side) |
| Wheel diameter |
|
| Wheelbase | Bogies: 2.700 m (8 ft 10.3 in) |
| Maximum speed | 90 mph (145 km/h) |
| Weight | 154.3 tonnes (151.9 long tons; 170.1 short tons) (4-car set)[6] |
| Traction system | IGBT |
| Prime mover(s) | 4 ×Deutz 16-litre V8turbo-diesel |
| Power output | 1,500 kW (2,000 hp) at wheel |
| Tractive effort | Starting: 160 kN (36,000 lbf) |
| Acceleration | 0.9 m/s2 (2.0 mph/s) |
| UIC classification | Bo′2′2′2′2′Bo′ |
| Safety system(s) | |
| Multiple working | Within class (max. 3 units) |
| Track gauge | 4 ft 8+1⁄2 in (1,435 mm)standard gauge |
| Notes/references | |
| Sourced from[7] unless otherwise noted. | |
TheBritish Rail Class 231[8] is a class of elevendiesel-electric multiple units of theFLIRT family, which have been built forTransport for Wales by Swiss rolling stock manufacturerStadler Rail. The first units entered service on 18 January 2023.[1]
The previousWales & Borders rail franchise operator,KeolisAmey Wales ordered the new trains. Although KeolisAmey was removed as the franchise operator and replaced by an operator of last resortTransport for Wales Rail, owned by the Welsh Government, the scheduled full fleet replacement continued.[9][10]
The units began testing in Switzerland in July 2021 and in November 2021 the first two units were delivered toCardiff Canton depot.[11]
The Class 231 units are currently used for services on theRhymney line and theVale of Glamorgan Line. They mostly operate betweenRhymney/Bargoed andBarry Island from Mondays to Saturdays, and betweenRhymney/Caerphilly andBarry Island on Sundays.[12]
Sometimes they operate on other valleys lines as well such as theMerthyr/Aberdare Lines, theCity Line and theTreherbert Line.
It is expected that they will operate the following services from around late 2025 or early 2026:
The official revenue launch of the Class 231 took place on 29 March 2023 atCaerphilly.[13]
Class 231 units have four passenger vehicles, along with a separate "Power Pack" vehicle at the centre of the unit that contains four diesel generator sets. The diesel generators comply withEU Stage V emissions regulations. All vehicles are linked by unpoweredJacobs bogies, while the outermost bogie at each end of each unit carries the traction motors.[7]
As of October 2024, TfW are considering fitting pantographs to these units to allow them to operate as "hybrid" or "bi-mode" (likeClass 755s), and have mobilised a project team to support the implementation of the conversion with Stadler.[14]
| Subclass | Operator | Qty. | Year built | Passenger cars | Unit nos. |
|---|---|---|---|---|---|
| 231/0 | Transport for Wales Rail | 11 | 2021–2022 | 4 | 231001–231011[2] |
