NER Class Y
No. 9772 at Hull Dairycoates Locomotive Depot 1947
|Type and origin|
|Gauge||4 ft 8 1⁄2 in (1,435 mm)|
|Driver diameter||4 ft 7 1⁄4 in (1.403 m)|
|Locomotive weight||87.5 long tons (88.9 t)|
|Boiler pressure||160 or 180 psi (1.1 or 1.2 MPa)|
|Cylinder size||16 1⁄2 in × 26 in (420 mm × 660 mm)|
|Tractive effort||26,140 or 29,405 lbf (116.28 or 130.80 kN)|
The North Eastern Railway (NER) Class Y (LNER Class A7) 4-6-2T tank locomotives were designed whilst Wilson Worsdell was Chief Mechanical Engineer, but none were built until 1910 by which time Vincent Raven had taken over.
The Class Y locomotives were intended for hauling coal trains and were developed from the NER Class X (LNER Class T1) 4-8-0T heavy shunters. However, they had larger boilers and smaller cylinders for higher working speeds. Some locomotives had superheaters and 160 psi boiler pressure while others were not superheated and had 180 psi boiler pressure. The reason for this curious disparity is not known. A total of 20 locomotives were built.
By the time the A7s entered LNER ownership with Grouping in 1923, the A7s had been relegated to shunting in the larger marshalling yards. Their power was invaluable when shunting heavy trains over the shunting hump. In the 1930s, Nos. 1136 and 1175 were allocated to hauling chalk quarry trains from Hessle Quarry to Stoneferry Cement Works, in the Hull area.
Heavy mineral traffic declined after the end of World War II, and the A7s moved to the Hull area, except for Nos. 1181 and 1192 which stayed at Stockton. At Hull, the A7s replaced the old Hull and Barnsley Railway (H&BR) types which were being withdrawn at that time.
All 20 locomotives passed to British Railways in 1948 and they were numbered 69770-69789.
The A7s were withdrawn between 1951 and 1957 and none have survived into preservation.
- Ian Allan ABC of British Railways Locomotives, 1948 edition, part 4, page 55