Number in Class: 40
Locomotive Specifications
|
|
| Engine Weight: 68.55 tons |
Tender Weight: 40.35 tons |
Total Weight: 108.9 tons | Adhesive Weight: 44.45 tons |
| Length over Buffers: 66' 11½" |
Total Wheelbase: 58' 0" | Engine Wheelbase: 33' 1½" |
Coupled Wheelbase: 14' 3" |
| Tender Wheelbase: 15' 10½" |
Driver Wheel Dia.: 54" | Cylinders HP: Two - 18" x 26" |
Cylinders LP: |
| Grate Area: 39.0 sq ft | Evaporative Area: 1469 sq ft |
Superheated Area: 283 sq ft |
Working Pressure: 200 psig |
| Tractive Effort: 24960 lbs f |
Coal Capacity: 6.0 tons | Oil Capacity: 1350 gals | Water Capacity: 4000 gals |
| Remarks: Although the 'K's had proved most satisfactory on main lines laid with 70 lb per yard, or heavier rail, there was an urgent need for a modern, powerful locomotive capable or running over secondary lines laid with rails weighing only 53-56 lb per yard. Thus a new "Mountain" type locomotive was designed and classified 'J'. It was of handsome appearance, the boiler being partly streamlined after the style of the New Haven Railroad's 'J400' class 4-8-4s. To eliminate un-necessary weight, the coupling and connecting rods were forged from manganese molybdenum alloy steel. The 'J' incorporated all the latest ideas of the 'Ka' but a noteworthy departure was the use of the American Baker valve gear. The tender was of the Vanderbuilt ype. Twelve J class locomotives were converted to oil burning and reclassified as Class 'Jb', and the bullet nose streamlining was gradually removed. The 40 locomotives were all built by North British. |
|
Glenbrook Vintage Railway, Auckland - J 1234, North British #24557/1939 Operating Mainline Steam Trust, Auckland - J 1236, North British #24559/1939 Restoring |
