|
The GCR Class 11E was a type of 4-4-0 steam locomotive used by the Great Central Railway for express passenger services. Ten were built in the railway's own workshops at Gorton, Manchester during 1913; they remained in service until the mid-1950s. ==History== In the early part of the 20th century, the Great Central Railway (GCR) had favoured the 4-4-0 wheel arrangement for express passenger services. They had bought 40 such locomotives to the design of their Locomotive Engineer, John G. Robinson (Robinson became Chief Mechanical Engineer in 1902), between 1901 and 1904, and these formed class 11B. These were found to be too small, and subsequently several classes of 4-4-2 and 4-6-0 locomotive were introduced for express passenger trains, with the 4-4-2 type predominating. After the class 1 4-6-0, which were larger than any of the others, proved disappointing, Robinson decided to reduce the size of these and designed a 4-4-0 which became Class 11E. Ten were built in 1913, and were immediately successful. Compared to the class 1 4-6-0, the omission of one coupled axle allowed a longer wheelbase between two adjacent axles of a 4-4-0 than with the 4-6-0, so the firebox could be positioned between the axles instead of on top of one of them; thus it could be deeper, giving better draughting which aided steaming. The shorter overall length meant that the boiler tubes were shorter, which also improved draughting. Unusually, outside admission was used for the piston valves of the cylinders. Conventionally, piston valve locomotives had inside admission, whereas outside admission was used with slide valve locomotives. Outside admission gives a shorter exhaust passage, with the consequent advantages of a lower back pressure and sharper blast, but with the disadvantage that the valve spindle glands must be made to withstand much higher pressures and temperatures. Robinson had previously used outside admission for his class 11D rebuilds from class 11B, and the new class 11E used the same cylinder casting as those rebuilds. When further 4-4-0s of similar capability to class 11E were required after World War I, these were given normal cylinders with inside admission for the piston valves, and so were placed in class 11F. Withdrawal occurred between March 1953 and November 1955. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「GCR Class 11E」の詳細全文を読む スポンサード リンク
|