| HR X class | |
|---|---|
| Power type | Steam |
| Designer | Peter Drummond |
| Builder | North British Locomotive Company |
| Build date | 1909–1912 |
| Configuration | 0-6-4T |
| UIC classification | C2'n |
| Gauge | 4 ft 8 1⁄2 in (1,435 mm) |
| Driver diameter | 60 in (1.524 m) |
| Trailing wheel diameter |
39 in (0.991 m) |
| Locomotive weight | 69 long tons (70 t) |
| Fuel type | Coal |
| Fuel capacity | 4.5 long tons (4.6 t) |
| Water capacity | 1,970 imp gal (9,000 l) |
| Boiler pressure | 180 psi (1.24 MPa) |
| Firegrate area | 22.5 sq ft (2.09 m2) |
| Heating surface: Tubes |
1,148 sq ft (106.7 m2) |
| Heating surface: Firebox |
120 sq ft (11 m2) |
| Cylinder size | 18½×26 in (470×660 mm) |
| Tractive effort | 22,082 lbf (98.23 kN) |
| Career | HR, LMS |
| Class | HR: X LMS: 4P |
| Number in class | 8 |
| Disposition | All scrapped |
The Highland Railway Drummond 0-6-4T or X class were large tank engines originally intended for banking duty.
Of Peter Drummond design, the first four were built by the North British Locomotive Company and delivered in 1909. A fifth was delivered in 1910, a sixth in 1911, and the last two in 1912.
The design was derived from that of the 0-6-0 tender engines and leading dimensions were very similar although the boiler and firebox are recorded as being 'larger' but by an unspecified amount.
They were not popular with their crews, many thought them heavy and clumsy, and several crews had problems with water capacity. It seems their axleboxes were not well-proportioned either as there are reports of consistent hot box problems.
| Year | HR No. | LMS No. | Notes |
|---|---|---|---|
| 1909 |
|
15300 | |
| 1909 |
|
15301 | Renumbered 66 in 1909 |
| 1909 |
|
15302 | Renumbered 68 in 1909 |
| 1909 |
|
15303 | |
| 1910 |
|
15304 | Renumbered 43 in 1913 |
| 1911 |
|
15305 | |
| 1912 |
|
15306 | |
| 1912 |
|
15307 |
All were withdrawn prior to nationalisation in 1948.
|
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