Classification

The classification system use by Queensland Railways consisted of a letter, indicating the number of driving axles, followed by a number, indicating the cylinder diameter in inches. This was confusing for two reasons: (1) it differed from the international system

UIC classification of locomotive axle arrangements

The UIC classification of locomotive axle arrangements describes the wheel arrangement of locomotives, multiple units and trams. It is set out in the International Union of Railways "Leaflet 650 - Standard designation of axle arrangement on locomotives and multiple-unit sets". It is used in much...

 and (2) it could lead to several classes having the same classification number. Where classification numbers were duplicated, the classes were usually distinguished by the name of the builder, e.g. A10 Baldwin, A10 Fairlie, A10 Neilson.

Number of driving axles	International classification	QR classification
1	A	-
2	B	A
3	C	B
4	D	C
3 (Tank locomotive Tank locomotive A tank locomotive or tank engine is a steam locomotive that carries its water in one or more on-board water tanks, instead of pulling it behind it in a tender. It will most likely also have some kind of bunker to hold the fuel. There are several different types of tank locomotive dependent upon... )		D

Improved versions of a similar class were given a second identical letter. For example the improved version of the D17 was the DD17.

Classes extinct by 1900

These classes are not listed on the Queensland's Railways Interest Group website.

• Queensland A10 Ipswich class locomotive
  Queensland A10 Ipswich class locomotive
  The A10 Ipswich class steam locomotive was a 2-4-0 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge. The “A”, is used to identify the number of coupled wheels, being four coupled wheels for the A10 class, followed by numerals indicating the cylinder diameter...
  
  

Classes surviving beyond 1900

• 4D10 – Ipswich Class
• 4D11½ Abt Class
• 6D11½ Crane Class
• 6D11½ Motor Class
• 6D13 – Originally F – Class
• 6D13½ Abt Class
• 6D13½ later B13½ Class
• 6D16 Class
• 6D17 later D17 Class
  Queensland D17 class locomotive
  The D17 class steam locomotive was a 4-6-4T locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge. The significance of the first "D" is in line with the QR loco classing system where the letter referred to the number of coupled wheels...
  
  
• 8D15 Class
• A10 Baldwin
  Queensland A10 Baldwin class locomotive
  The A10 Baldwin class steam locomotive was a 4-4-0 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge. The “A”, is used to identify the number of coupled wheels, being four coupled wheels for the A10 class, followed by numerals indicating the cylinder diameter...
  
   – Originally American Passenger Class
• A10 Fairlie
  Queensland A10 Fairlie class locomotive
  The A10 Fairlie class steam locomotive is a 2-4-0 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge...
  
   – Originally A Class
• A10 Neilson
  Queensland A10 Neilson class locomotive
  The A10 Neilson class steam locomotive is a 0-4-2 locomotive of the Queensland Railways.The locomotives operated on 1,067 mm gauge...
  
   – Originally B Class
• A11 – Originally Large A Class
• A12 – Originally American Passenger Class
• A12 (small) – American Passenger Class
• A14 Class
  Queensland A14 class locomotive
  The A14 class steam locomotive was a 4-4-0 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge...
  
  
• AC16 Class
  Queensland AC16 class locomotive
  The Queensland AC16 class locomotive is a 2-8-2 steam locomotive of the Queensland Railways . The locomotives operated on 1,067 mm gauge....
  
  
• Australian Standard Garratt
  Australian Standard Garratt
  The Australian Standard Garratt was a Garratt steam locomotive designed in Australia during the Second World War, which was used on narrow gauge railway systems in Queensland, South Australia, Western Australia and Tasmania.- Overview :...
  
  
• B11 – Originally C Class
• B11 Baldwin Class
• B12
  Queensland B12 class locomotive
  The B12 class steam locomotive was a 2-6-0 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge. The “B”, is used to identify the number of coupled wheels, being six coupled wheels for the B12 class, followed by numerals indicating the cylinder diameter of twelve...
  
   – Originally E Class
• B13
  Queensland B13 class locomotive
  The B13 class steam locomotive was a 4-6-0 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge...
  
   Class
• B15 Class
• B15con Class
• B16½ Class
• B17 Class
• B18¼ Class
  Queensland B18¼ class locomotive
  The B18¼ class steam locomotive was a 4-6-2 locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge...
  
  
• BB18¼ Class
  Queensland BB18¼ class locomotive
  The BB18¼ class locomotive was a type of 4-6-2 steam locomotive operated by the Queensland Railways.Fifty-five BB18¼ class locomotives were built. The first batch of 35, numbered from 1011 to 1045, were built in 1950 by the Vulcan Foundry in Newton-le-Willows, Lancashire. The final batch of 20,...
  
  
• Beyer-Garratt Class
  Queensland Beyer-Garratt class
  The Queensland Beyer-Garratt class locomotive was a 4-8-2+2-8-4 steam locomotive of the Queensland Railways. The locomotives operated on 1,067 mm gauge.-Overview:...
  
  
• C13 Baldwin Class
• C13 Dubs – Originally Small Consolation Class
• C15 – Originally Large Consolation Class
• C16 Baldwin – Large Consolidation Classba
• C16 Class
  Queensland C16 class locomotive
  The C16 class steam locomotive is a 4-8-0 locomotive of the Queensland Railways QR. The locomotives operated on 1,067 mm gauge. The “C”, is used to identify the number of coupled wheels, being eight coupled wheels for the C16 class, followed by numerals indicating the cylinder diameter of sixteen...
  
  
• C17 Class
  Queensland C17 class locomotive
  The C17 class locomotive was a 4-8-0 locomotive of the Queensland Railways. . The locomotives operated on narrow gauge.The design was so successful that 227 locomotives were built from 1920 when the first engine N° 15 entering service through until 1953 when N° 1000 was delivered. The 22 NM...
  
  
• C18 later CC19 Class
• C19 Class
  Queensland C19 class locomotive
  The Queensland C19 class steam locomotive was a 4-8-0 steam locomotive of the Queensland Railways .The locomotives operated on 3 ft 6 in gauge...
  
  
• DD17 Class
  Queensland DD17 class locomotive
  The DD17 class steam locomotive was a 4-6-4T locomotive of the Queensland Railways .The locomotives operated on 1,067 mm gauge. The significance of the first "D" is in line with the QR loco classing system where the letter referred to the number of coupled wheels. "A" refers to 4 coupled...
  
  
• PB15 (1924) Class
• PB15 Class

Ipswich workshops

The old Ipswich workshops of Queensland Railways built locomotives up to 1879 when a Select Committee recommended that no further locomotives be built there. The new Ipswich workshops began building locomotives in 1903.