NZR TR class

New Zealand TR class

NZR built TR 874 at Dunedin in 2013. Bagnall built TR 156 at Ferrymead.

Type and origin Power type Diesel-Mechanical/Hydraulic Builder Drewry Car Co (29), A & G Price (41), W G Bagnall (7), Hitachi (6), NZR, Hillside Workshops (9), Muir-Hill (4), Hudswell Clarke (3), FC Hibbert (2), Robert Stephenson and Hawthorns (5) Build date 1936-78

Specifications AAR wheel arr. 0-4-0, 0-6-0 Gauge 1,067 mm (3 ft 6 in) Loco weight 9.4–20.8 t (9.3–20.5 long tons; 10.4–22.9 short tons) Prime mover Detroit 4-71, Gardner 8LW, Gardner 6L3, Gardner 6LW, McLaren M6, Gardner 6LX, Cummins 6 cyl

Performance figures Maximum speed 24–40 km/h (15–25 mph)

Career Operators NZGR, New Zealand Railways Corporation, Tranz Rail, Toll Rail, KiwiRail Number in class 90 Nicknames "Rosie" (TR 107), "Timmy" (TR 163), "Tonka Toy" (TR 534) First run 1936 Current owner KiwiRail Disposition 32 in service; 1 out of service; 36 preserved, 32 scrapped, 1 in service for an industrial use.

The New Zealand TR class is a class of diesel shunting locomotives built by many different manufacturers. Many of these locomotives have been withdrawn, but some are still in service. The first locomotive of this class was built by NZR in 1924. The most powerful were Japanese-built Hitachi TRs, with 138 kW Cummins engines.

The original batch of six 0-4-0 TRs, 13-18, supplied in 1936 by the Drewry Car Co., was supplemented by TR 20-22 and 30-36 in 1939-40. These were powered by Parsons petrol engines. In 1939-40 seven 0-6-0 TRs (the only ones of this type), 23-29, were supplied and were fitted with Leyland 10-litre (610 cu in) petrol engines Wairarapa railcars. Finally, in 1950 five 0-4-0 TRs, 60-64, with diesel engines were introduced. The locomotives were built at various UK works including Vulcan Foundry and Robert Stephenson and Hawthorns. Practically all Drewry TRs are out of service today.

W. G. Bagnall built seven TRs in 1956-57. The first five were supplied with McLaren M6 engines, the last two with Gardner 6L3 engines, all with a Self-Changing Gears 4-speed gearbox. The McLaren engines were unsuccessful, so from 1973 TR 150-154 were re-engined with the Gardner 6LX with Twin Disc torque converters. These TRs were the heaviest and one of the more powerful types.

The long established NZ engineering firm A & G Price of Thames supplied a total of 39 TRs, making them the largest single builder. Four different models were supplied: the Model 3 (TR 100-109), with Gardner 6LW engine and Self Changing Gears 4-speed gearbox; the Model 9 (TR 110-118), powered by a Gardner 6LW engine and Twin Disc torque converter; the Model 4 (TR 157-161), McLaren M6 engine and SCG 4-speed gearbox; and the Model 6 (TR 162-176), engine Gardner 6L3, also SCG 4-speed gearbox. The McLaren engined TRs were re-powered from 1975 with Gardner 6LX engines and the gearbox was replaced with a Twin Disc torque converter.