The British Rail Class 31 diesel locomotives, also known as the Brush Type 2 and previously as Class 30, were built by Brush Traction from 1957 to 1962. They were numbered in two series, D5500-D5699 and D5800-D5862. Construction of the first locomotive was completed in the final week of September 1957, and the handing-over took place on 31 October. The first Class 31 entered service in November 1957, after the launch of the Class 20 locomotive and was one of the Pilot Scheme locomotives ordered by British Railways to replace steam traction.
Engines
They were originally built with Mirrlees JVS12T (D5500–D5519) and engines and Brush electrical equipment, but the engines were not successful and in 1964 D5677 was fitted with an English Electric 12SVT engine (similar to the 12CSVT used in the Class 37 but without an intercooler) rated at . The trial proved successful, and between 1965 and 1969 the entire class was re-engined. The de-rated engine was used as it was the maximum the electrical system could accept.
Classification
The Mirrlees-engined locomotives were originally known as Class 30 under TOPS, with re-engined examples joining Class 31. The class was originally intended for service on the Eastern Region, but gradually became common in both the Western and London Midland regions too.
Sub-classes
Several sub-classes of Class 31 exist:
- 31/0 - First batch of locos, fitted with Red Circle electro-magnetic control equipment were always easily recognisable as they did not have the headcode box mounted on the roof above the cab, leading to the nickname "Skinheads". These pilot scheme locomotives were non-standard in having Electro-Magnetic Multiple-Working control equipment, and were limited to . After being involved in a serious collision D5518 was rebuilt in September 1967 as a standard locomotive, with indicator boxes, and blue star coupling code.
They were allocated to East Anglian sheds throughout their service, ending up allocated to Stratford, their initial shed, and latterly sporting that depot's trademark silver roof. Upon withdrawal four locomotives were converted at Stratford into train pre-heating units. Locomotives 31013, 31002, 31014 and 31008 were renumbered ADB968013 to ADB968016 in the order given; ADB968014 was allocated to Bounds Green depot on the Great Northern main line and ADB968015 was based at Great Yarmouth, while the remaining two were allocated to Stratford.
Class 31/1
thumb|right|Class 31/1 on Sharnbrook bank with a short van train in April 1985
The first few locos externally had much in common with the original 31/0s as twenty lacked the roof mounted headcode box (D5520–29/35/39/42/47/51/52/55/56/59/62), and fifteen were also limited to (D5520–D5534), but were otherwise the same as subsequent locos. The whole sub-class had steam heating boilers fitted, had the Blue Star Electro-Pneumatic multiple-working controls as found on many other BR classes. The Class 31/1s could be found on a variety of secondary and relief passenger duties as well as parcels and freight traffic. While used in East Anglia, with locos allocated to Stratford and March depots, they were found throughout the Eastern Region of BR with Finsbury Park sporting a large allocation along with the depots at Tinsley, Immingham and Thornaby. Locos were also allocated to Bristol Bath Road and Old Oak Common on the Western Region, where they could be found working passenger trains as far west as Barnstaple and Paignton. In the early 1980s Healey Mills and Bescot on the Midland Region also gained an allocation as replacements for Class 25s.
Class 31/4
thumb|31418 at [[Birmingham New Street railway station|Birmingham New Street]]
The Class 31/4s, numbered from 31400 to 31469, were conversions of 31/1s to which electric train heating (ETH) was fitted. They had an ETH index of 66, equivalent to 330 kW, which was sufficient to power trains of up to eleven Mk 3 carriages. This allowed them to pre-heat long trains moving between depot and a station for a service to be worked by a larger locomotive. When passenger services were worked by 31/4s they rarely exceeded four or five carriages. 330 kW accounted for about a third of the total electrical power output. When ETH was being supplied, the traction power output of the 31/4 subclass was therefore limited to around two-thirds of that of the non-ETH variants; this did not help the performance of an already somewhat underpowered locomotive.
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Refurbishment
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Class 31/5
thumb|right|31549 at [[Peterborough railway station|Peterborough in 1994]]
In the late 1980s with increased use of "Sprinter" type units on previously loco hauled diagrams, there were ETH fitted Locomotives to spare and with this in mind, some Class 31s were selected to have their ETH cables removed from the front buffer beam. This was done to try to prevent passenger sectors of BR borrowing the locomotives from the Freight sectors, and to cut down on maintenance of surplus equipment. The re-numbering was achieved by simply adding 100 to the existing TOPS number i.e. 31407 became 31507. When the re-numbering was taking place, most locos were still in standard BR Blue livery and the 4 in the number was painted over and a 5 placed over the top. Some of the sub-class were painted into Civil Engineers all over Grey livery, although most were subsequently painted into the "Dutch" Yellow and Grey livery. Only 31530 (Sister Dora), 31544 (Keighley and Worth Valley Railway) and 31568 (The Engineman's Fund) were named when numbered as a 31/5. 31544 was also notable as the only one of the sub-class with the original "skinhead" style cabs without the route indicators on the roof.
Class 31/6
Only two locomotives (31601 and 31602, formerly 31186 and 31191 respectively ) received this modification, performed during their time with Fragonset Railways. This modification means they are through wired for Electric Train Heating (ETH) but cannot actually provide it. This means they can be coupled to a train behind another locomotive, and the front locomotive is still able to heat the train via the wiring on the 31/6. 31601 is now preserved at the Ecclesbourne Valley Railway where it regularly operates trains
Nicknames
The class were given a number of nicknames. The Class 31/0s were known as Toffee Apples, due to the shape of the control lever. More common names for the whole class were Goyles (short for "gargoyles" referring to the ugliness some people saw in the design), Peds ("Another derogatory name associating the locomotives with pedal cars in terms of speed and pulling power")
Accidents and incidents
thumb|right|An unidentified Class 31 with accident damage
- On 11 September 1975, 31150 was involved in a head-on collision at Corby Tunnel, with a loose brake van and coke wagons.
- On 25 February 1979, locomotive 31421 was hauling an engineering train that was working under a possession between and , Hampshire. The adjacent line was open to traffic. A crane in the engineering train was foul of the other line when it was struck by a passing passenger train. One person was killed and nine were injured.
- On 9 March 1986, locomotive 31436 was hauling a passenger train that was in a head-on collision with two light engines at , Derbyshire due to a signalman's error. One person was killed. Lack of training and a power cut were contributory factors.
- On 20 February 1987, a freight train ran away and was derailed by trap points at North Junction, Chinley. Locomotive 31440 was hauling a train that collided with the wreckage.
- On 28 October 1988 two unmanned Class 31 locos (31202 and 31226), presumably with brakes not fully applied, rolled off together along a short siding at North London's Staples Corner. After demolishing the buffer stop they ran down the embankment on to the North Circular Road, although nobody was hurt. The second loco of the pair landed on the roof of the leading one, remaining precariously balanced. They were both withdrawn after the incident.
Commercial operators
{| class="wikitable floatright"
|+Distribution of locomotives,<br />March 1974
|-
|colspan=3 |
|-
|colspan=3 |
|-
!Code ||Name ||Quantity
|-
|style="text-align:center" |BR ||Bristol Bath Road ||style="text-align:right" |13
|-
|style="text-align:center" |CW ||Cricklewood ||style="text-align:right" |2
|-
|style="text-align:center" |FP ||Finsbury Park ||style="text-align:right" |51
|-
|style="text-align:center" |GD ||Gateshead ||style="text-align:right" |8
|-
|style="text-align:center" |HO ||Holbeck ||style="text-align:right" |15
|-
|style="text-align:center" |IM ||Immingham ||style="text-align:right" |41
|-
|style="text-align:center" |MR ||March ||style="text-align:right" |52
|-
|style="text-align:center" |OC ||Old Oak Common ||style="text-align:right" |19
|-
|style="text-align:center" |SF ||Stratford ||style="text-align:right" |24
|-
|style="text-align:center" |TE ||Thornaby ||style="text-align:right" |12
|-
|style="text-align:center" |TI ||Tinsley ||style="text-align:right" |22
|-
|style="text-align:center" |YK ||York ||style="text-align:right" |4
|-
!colspan=2 scope=row |Total:
|style="text-align:right" |263
|}
Eastern Rail Services
In 2022 the only operational class 31/4 outside preservation was 31452 which is based at Great Yarmouth.
English, Welsh & Scottish
Before the introduction of Class 66, English Welsh & Scottish (EWS) took control of the Class 31s from the Mainline Freight and Trainload Freight companies. 31255 became the locomotive for the EWS livery paint trials but never ran on the main line and spent its life at Toton until being preserved in January 1999. 31466 was repainted into EWS colours for the Toton TMD open day in May 1998 and soon became the only one of the class to be in traffic running in the EWS colours until being preserved in February 2001. In their final days of EWS ownership, 31110 (scrapped at TJ Thompson's, Stockton in April 2007) was repainted into BR green in the summer of 1999 and featured its original number D5528 to mark the end of their working lives with EWS and worked the last EWS Class 31 hauled railtour. The final four EWS locomotives were withdrawn in February 2001. Of the two EWS liveried locos, both 31255 and 31466 are preserved, 31255 based at the Mid Norfolk Railway and 31466 based at the North Yorkshire moors railway.
Hanson and Hall
Created in 2018, in 2022 Hanson and Hall had one of the three remaining operational Class 31s outside preservation. 31106 was stored at Bury on the East Lancashire Railway in Rail Blue livery.
Mainline Rail
After the demise of FM Rail, several of its Class 31s passed to Mainline Rail, operated by RMS Locotec. As of November 2008, four 31/4s and one 31/6 were owned by RMS Locotec, which is a subsidiary of British American Railway Services.
Nemesis Rail
31128, an ex-Fragonset locomotive, is owned by Nemesis Rail and based at Burton upon Trent. In 2022 this locomotive is one of only three remaining operational Class 31s outside of preservation, and has been returned to BR Blue livery.
Network Rail
alt=31105 passes Chesterfield working 4Q25 Derby RTC - Immingham TMD Test train|thumb|31105 passes [[Chesterfield, Derbyshire|Chesterfield working 4Q25 Derby RTC - Immingham TMD Test train]]
Network Rail operated a fleet of four Class 31 locomotives31105, 31233, 31285, and 31465to haul test trains around the network. The locomotives were purchased from Fragonset Railways, and overhauled at its Derby workshops. They were repainted in Network Rail's then new all-over yellow livery. 31285 and 31465 were offered for sale by tender in July 2015, and 31233 and 31105 in August 2018.
Prior to operating its own locomotives, Network Rail's predecessor, Railtrack, had hired two Class 31 locomotives from Fragonset. These two locomotives, 31190 and 31601, were repainted in Railtrack's blue and lime green livery. With the overhaul and entry into service of Network Rail's own locomotives, these two engines were returned to Fragonset. (They are now owned by British American Railway Services, based at Washwood Heath in Birmingham.)
Locomotive 31106, formerly Spalding Town, is privately owned by Howard Johnston, and after a period of lease to Fragonset, FM Rail, and RVEL which included extensive main line running for 11 years, including working as far north as Oban in Scotland, is based at the Weardale Railway. After inspection, it was successfully started on 17 October 2017 and moved under its own power for the first time in four years. Johnston purchased three more of the class from EWS, but they acquired new owners; 31107 (scrapped by C F Booth at Rotherham in May 2009, following a staged collision with a Renault Espace on a level crossing during Top Gear Series 9, Episode 5 in 2006 to demonstrate the danger of trying to beat a train at a crossing), 31289 (preserved at the Northampton and Lamport Railway), and 31301 (scrapped).
The last active Network Rail Class 31 was 31233, with it operating its last test trains in March 2017. In August 2018, Network Rail offered its final two Class 31s (31105 and 31233) for sale; both were purchased for preservation at Mangapps Railway Museum in Essex.
|align="left"|First-built locomotive, now part of the National Collection.
|-
|D5518
|31101
| –
| –
| –
|align="left"|BR Blue
|align="left"|Avon Valley Railway
|align="left"|Undergoing repairs
|-
|D5522
|31104
|31418
| –
|align="left"|Boadicea
|align="left"|BR Blue
|align="left"|Midland Railway - Butterley
|align="left"|Undergoing restoration
|-
|D5523
|31105
|31105
| –
|align="left"|Radio Caroline
|align="left"|BR Blue
|align="left"|Mangapps Railway Museum, Essex
|align="left"|Operational
|-
|D5524
|31106
| –
| –
| –
| style="text-align:left;"|BR Blue
| style="text-align:left;"|East Lancashire Railway
|align="left"|Undergoing overhaul
|-
|D5526
|31108
| –
| –
| –
| style="text-align:left;"|Railfreight Grey
| style="text-align:left;"|Midland Railway - Butterley
|
|-
|D5533
|31115
|31466
| –
| –
| style="text-align:left;"|EWS Maroon/Gold
| style="text-align:left;"| North Yorkshire Moors Railway
| style="text-align:left;"|
|-
|D5537
|31119
| –
| –
| –
| style="text-align:left;"|BR Blue
| style="text-align:left;"|Embsay and Bolton Abbey Steam Railway
| style="text-align:left;"|Stored
|-
|D5546
|31128
|–
|–
| style="text-align:left;"|Charybdis
| style="text-align:left;"|BR Blue
| style="text-align:left;"|Nemesis Rail, Burton-on-Trent
| style="text-align:left;"|Operational
|-
|D5547
|31129
|-
|D5609
|31186
|31601
| –
| –
|align="left"|DCR Grey
|align="left"|Ecclesbourne Valley Railway
|
|-
|D5613
|31190
| –
| –
|align="left"|
|align="left"|Golden Ochre
|align="left"|Plym Valley Railway
|
|-
|D5627
|31203
| –
| –
|align="left"|Steve Organ G.M.
|align="left"|BR Green
|align="left"|Pontypool and Blaenavon Railway
|
|-
|D5630
|31206
| –
| –
| –
|align="left"|Civil Engineers
|align="left"|Ecclesbourne Valley Railway
|align="left"|Rescued from Booth's Scrapyard in 2006
|-
|D5631
|31207
| –
| –
| –
|align="left"|BR Green
|align="left"|North Norfolk Railway
|align="left"|One of the final three locomotives operated by EWS
|-
|D5634
|31210
| –
| –
| –
|align="left"|Railfreight Grey
|align="left"|Dean Forest Railway
|align="left"|Undergoing restoration
|-
|D5637
|align="left"|Stored
|-
|D5660
|31233
| –
| –
| –
|align="left"|Network Rail Yellow
|align="left"|Mangapps Railway Museum, Essex
|align="left"|Operational
|-
|D5662
|31235
| –
| –
| –
| style="text-align:left;"|BR Blue
| style="text-align:left;"|Dean Forest Railway
| style="text-align:left;"|Stored
|-
|D5683
|31255
| –
| –
| –
| style="text-align:left;"|EWS Maroon/Gold
| style="text-align:left;"|Mid-Norfolk Railway
| style="text-align:left;"|Repainted in EWS livery for paint trials
|-
|D5684
|31256
| style="text-align:left;"|Operational
|-
|D5801
|31271
| –
| –
| style="text-align:left;"|Stratford 1840-2001
| style="text-align:left;"|Trainload Construction
| style="text-align:left;"|Llangollen Railway
|
|-
|D5809
|31279
|-
|D5814
|31414
|31514
| –
| –
| style="text-align:left;"|Dutch Civil
| style="text-align:left;"|Midland Railway - Butterley
| style="text-align:left;"|Undergoing repairs
|-
|D5817
|31285 It was eventually aired on BBC Two on 25 February 2007, shortly after the Grayrigg derailment. A repeat of the programme was pulled following a further level-crossing accident.
Locomotive 31120 appears in The Railway Series book Gordon the High Speed Engine.
Model railways
In 1962 Tri-ang launched its first version of the BR Class 30 (with headcode boxes) in OO gauge. Airfix model railways also chose to produce a Class 31 when Airfix entered the model train market in 1975. Lima also produced a OO scale model, in both "skinhead" and headcode box versions. Hornby have produced a finescale OO scale model since 2004; both body styles are available in various liveries. Hornby have also produced a basic representation of the prototype as part of their Railroad range in BR Blue, and BR Green whilst past examples have carried a variety of liveries. On 23 February 2022 Accurascale announced their own OO model, due out in 2023 which has also been joined by a range from Bachmann.
In the 1970s, Lima produced British N gauge models of the Class 31 in BR blue and BR green. In 2010, following Bachmann's acquisition of Graham Farish, the earlier Graham Farish Class 31 model was issued in BR green with a new chassis. In 2017, Graham Farish introduced a British N gauge model of the refurbished Class 31.
In 2013, Heljan introduced O gauge models of the Class 31 in BR blue and BR green liveries.