Herbert William Garratt (1864-1913), Inspecting Engineer for the New South Wales Government, brought to Beyer, Peacock the basic principle of locomotive articulation, which has since borne his name. The drawing for the patent specification was taken out by Garratt in 1907. However, his overseas commitments and sudden death on 25th September 1913 meant that most of the development of the design was carried out by Beyer, Peacock themselves.
A “Beyer Garratt” consists, virtually, of two ordinary locomotive chassis, placed some distance apart, and held together by a girder frame which supports the boiler and firebox. The weight of boiler and frame is transmitted to the two chassis by means of pivots at either end, and this enables the engine to traverse sharp curves which would not be possible with a conventional locomotive of the same size.

The Garratt design also had a number of other advantages over traditional locomotives. With the boiler suspended between two power units, there was unrestricted space available for wide and deep fireboxes and barrels of large diameter. Another feature was the spreading the weight of the engine over a great many axles. In many countries, as traffic increased, the trains could not be lengthened because conventional engines had reached the limit of their power due to restrictions of axle loading. Alternative solutions were either double-heading longer trains or re-building and re-laying large parts of the lines to take heavier locomotives. Either method was expensive, but the Garratt provided a cheaper answer. One boiler, which needed only one crew, could be placed on two power bogies with the result that the tractive effort could be doubled and the weight distributed over a large number of wheels. Garratt locomotives were particularly effective on narrow gauge railway lines where the restricted loading gauge forbids the use of very large and powerful boilers on ordinary engines.

By the 1920s, the Garratt type had proved its superiority of other forms of articulated locomotives and over time orders were received from Africa, Asia, Australia, Europe, New Zealand, and South America. Beyer, Peacock & Company purchased sole rights of manufacture in Britain. After the patents ran out in 1928, the company began to use the name “Beyer-Garratt” to distinguish the locomotives they had manufactured.

Altogether Beyer, Peacock constructed 1023 Beyer Garratts and granted manufacturing licenses other companies, the most significant being Société Franco Belge de Materiel du Chemins de fer, Raismes, France. In the busy post war years, Beyer, Peacock built 449 Beyer Garratts at their Gordon Works and sub-let or licensed another 235 Beyer Garratts for construction by other companies.


  • Wheel arrangement


  • Cylinders (diameter X stroke) ins. (4)

    16” x 24”

  • Coupled Wheels diameter ins.


  • Length over Couplers

    87’ 5”

  • height_over_chimney

    12’ 3”

  • Axle Load

    10 tons 13 cwt

  • Boiler Pressure psi


  • Heating Surface of tubes - sq feet


  • Heating Surface total - sq feet


  • Grate area - sq feet


  • Weight - adhesive - tons

    84 tons.18 cwt

  • Total weight


  • Fuel Oil Capacity


  • Tractive Effort - lbs. (85%)


  • Factor of Adhesion


  • Valve Gear


Zig Zag Railway

Beyer Garratt Nº 402

In April 1951, the South Australian Government approved of the purchase of ten Beyer Garratt locomotives. The necessity for the procurement of additional locomotives was brought about mainly by the inability of the T-class 4-8-0 locomotives to handle the increased tonnages of Leigh Creek coal and to a lesser extent, the ore concentrates traffic on the Broken Hill line.

The order for the locomotives, which were subsequently designated the 400 class, was placed with Beyer, Peacock & Co. Ltd., of Manchester, United Kingdom. As that company’s Gordon Works were fully occupied, the order was sub-contracted to Société Franco Belge de Materiel du Chemins de fer, Raismes, France.

Nos. 400 to 404 were shipped from Dunkirk, France, during early April 1953, in the MS Belnor and arrived at Port Pirie, South Australia, on 1st June 1953. Three days after arrival, unloading of the locomotives commenced and they were taken to the Port Pirie locomotive depot, where they were partially put together for haulage to Peterborough, where final assembly was completed. The other five locomotives followed a similar course and arrived in Port Pirie on 18th December 1953.

The engines were, in all essentials, identical with East African Railways 60 Class and were thus a development of the War Department Garratts. However, while the 60 Class were metre gauge built to enable conversion to 3’ 6” gauge, the 400 Class were designed so as they could be regauged to either 4’8½” or 5’ 3” gauge. The locomotives were built as oil burners with the ability be converted to coal firing if necessary. In the event of their conversion to coal fuel, provision was made for the fitting of a mechanical stoker. The fuel oil tank, with a capacity of 1400 gallons (6 tons) of fuel oil is situated above the water tank on the rear engine unit.

Nº 402 entered service on 16th July 1953 and carried Société Franco-Belge builder’s Nº 2975 as well as Beyer, Peacock builder’s Nº 7624. She achieved two notable accomplishments in the later years of her career. On 31st October 1968, Nº 402 was the first and only Garratt to reach Quorn. The following year, on 12th October 1969, Nº 402 became the only Garratt to work into Broken Hill. Cockburn on the NSW border being the normal limit of their working.

By 1955 the Beyer Garratts had taken over most of the traffic on the Broken Hill line, however, their reign was short lived. The introduction of the 830 Class diesel electrics saw the Garratts replaced and by 1963, they were placed in storage.

The standard gauge link between Port Pirie and Broken Hill, to replace the original 3’ 6” (1067mm) gauge line had long been suggested, but the project only got under way in 1963, construction commencing in a small way in July of that year. The venture was originally scheduled to have been completed at the end of 1968, but delays resulted in that not being accomplished until 1970.

As the 830 Class diesels needed to be taken out of service for gauge conversion, the decision was taken to return six Garratts, including 402, and a number of T Class to service during that period. There was a limited return to steam working in 1968 and this increased during 1969. The end for steam finally came on 10th January 1970 when Nº 404 arrived at Peterborough at 7.30am that morning.

Engines numbers 403, 405, 407 and 408 did not survive to the end but the remaining six, which did, were all condemned on 1st May 1970. Two of the class survive today. Nº 409 went to the Mile End Railway Museum, now the National Railway Museum, on 17th November 1970. Nº 402 was sold to the Zig Zag Railway in 1973 and finally arrived at Lithgow in 1976.

Sources of Information

ARHS Bulletin Nº 231 July 1955

Beyer, Peacock Locomotive Builders to the World – R L Hills & D Patrick

Garratt Locomotives of the World – A E Durrant

The Garratt Locomotive – Gavin Hamilton



Other Locomotives

10 Class

10 Class Diesel Hydraulic Locomotives

AC16 C16 Tender

AC16 Class Locomotives

BB18 Class Locomotives

BB18¼ Class Locomotives

Beyer Garratt Locomotives

C17 Locomotive

C17 Class Locomotives


DD17 Class Locomotives