The Northern Ireland Railways DH class was a class of three diesel-hydraulic shunting locomotives obtained in 1969. All three have now been withdrawn, and two have since been rebuilt for work in Sri Lanka. Early service life The DH class of Northern Ireland Railways consisted of three diesel-hydraulic shunting locomotives numbered 1, 2 & 3. They were built by the English Electric Company at their Vulcan Foundry works in Newton-le-Willows in 1969. The works numbers 3954–3956 in the EE list, and D1266–D1268 in the VF list. They were of 0-6-0 wheel arrangement and fitted with Dorman 12QTV engines of , connected to an EE Twin Disc torque converter and a Wiseman final drive. They weighed and had a maximum speed of . They are often referred to with their, "DH," prefix. The locomotives were of EE's standard 'Stephenson' class, and were obtained primarily for shunting work, trip freights and engineer's trains. Locomotive No. 1 was the first to enter service on 31 July 1969, with No. 2 following on 27 September and No. 3 on 4 October. However, the locomotives were not particularly successful due to problems with the engines overheating regularly while in service. Withdrawal from service and initial preservation All three were put into store during the late 1980s, the first in 1986 and the last two in May 1989. The Irish Traction group had approached NIR in August 1989 hoping to run a farewell excursion with No. 2 in September 1989, but this plan failed after No. 2 suffered a catastrophic engine failure on Saturday 9 September 1989 (the day before the excursion), despite having been overhauled by NIR at York Road Works. Both Nos. 2 and 3 ended up in secure storage at Larne Harbour, where the Diesel engines, torque converters and final drives were removed in 1991. It was originally intended to put the locomotives on display at Lisburn, Belfast Central, and Londonderry to celebrate the 150th anniversary of railways in Northern Ireland, and in mid-1989, locomotive No. 1 had its engine, torque converter and final drive removed at York Road works before being repainted in NIR red and moved to the Lisburn Engineer's yard; unfortunately, difficulties in placing the engine meant it was shunted to the back of the yard. Preservation In September 1994, the Irish Traction Group purchased the three locomotives from NIR and moved them south to their restoration base at Carrick-on-Suir.