- A.N. Other
- Ship design and development
- RAN Ships
- None noted.
- June 2019 edition of the Naval Historical Review (all rights reserved)
By Bob Hetherington
This story was first published in All Hands, the magazine for volunteers at the Australian National Maritime Museum (ANMM), and is reproduced with their and the author’s kind permission.
Just when reciprocating steam engines were looking like a dead duck, along came WWII and a new lease of life.
‘Up and Downers’ was the nickname given to the reciprocating steam engines which powered the Industrial Revolution. We have a classic example of one in the Australian National Maritime Museum’s Navy Gallery, but it’s not widely known how they got a second wind and powered the Liberty Ships which changed the course of WWII. And there’s an Australian connection. Up and Downers developed from the single cylinder steam engines which drove machines, ships and locomotives in the early 1800s. It was soon realized that coal consumption could be reduced by using the energy remaining in the steam leaving the cylinder, and triple expansion engines were introduced to feed the exhaust steam from the first (high pressure) cylinder into a second cylinder and then feeding its exhaust into a third (low pressure) cylinder. The pistons in each cylinder were connected to a common shaft which turned the wheels of industry. By the turn of the century triple expansion engines had become standard for marine propulsion. They had the advantage that they could be coupled directly to the propeller shaft and they ran at speeds suited to propeller efficiency.
However, a rival soon appeared in the form of the steam turbine. Turbines generate a rotary rather than reciprocating (up and down) motion with the advantages of lower vibration, lower weight, smaller dimensions, fewer moving parts and lower maintenance. By the early 1900s turbines were replacing Up and Downers and their low vibration was a big plus for the prestigious passenger liners of the time. Olympic and Titanic were fitted with a combination of both types of engine but a few years earlier Cunard had taken the plunge and chosen all-turbine drive for Lusitania andMauretania.Turbines operate at high speeds and need elaborate precision reduction gearing to drive propellers at efficient speeds, typically 80–120 rpm. Specialist engineering companies grew up to design and build the gear trains needed for marine propulsion. By the 1920s marine diesel engines had made their appearance (they are almost universal today); in 1924 the Swedish-American Line Gripsholmbecame the first diesel powered liner to cross the Atlantic. It seemed to be the end of the line for the Up and Downers.
World War II erupted and it became clear that the Allies would not prevail without a massive supply of materials from the United States to Britain. This required a huge and urgent expansion of merchant shipping capacity and the Liberty Ships program was launched to make up the shortfall.
These ships were designed to be simple, cheap, quick and easy to build and to operate (at relatively slow speeds) under the convoy system. The idea was to have the components built in various locations outside Britain with the ships assembled and launched on the U.S. east coast.
Engines also needed to be simple, reliable and quick and cheap to build. Although steam turbines and diesel were by now the prevailing technology there were two major problems: Diesel fuel was in short supply and there was an acute bottleneck in the availability of the gear trains needed for turbines; new designs would be needed to cater for the slower ship speeds. This engineering capacity was dedicated to production and maintenance of warships. Time was absolutely critical so it was decided to dust off a proven ‘up and down’ design and standardise it so it could be built quickly in existing engineering facilities. The engine chosen was a tried and tested design from the North Eastern Marine (NEM) Company of Sunderland and Wallsend, producing 2500 HP at 76 rpm. These were fitted not only to U.S. built Liberty ships but to Fort, Park and Empire ships built in the UK and Canada. No less than 2075 Liberty ships were to be built, and the choice of the NEM engine proved to be a very good one. In this sense the Up and Downer really did help to save the day.
At the same time a similar story played out in Australia, albeit on a smaller scale, and again Up and Downers proved their worth. They were fitted to the sixty Bathurst class corvettes built here during the War. In 1938 the Australian Commonwealth Naval Board (ACNB) proposed a general purpose local defence vessel which would be easy to construct and operate and in 1939 the RAN completed a design for a 680-ton vessel with a speed of 15 knots to be locally built and, yes, fitted with a triple expansion steam engine which could be constructed in the existing workshops of train locomotive manufacturers. This was a demanding project for the local industry. Cockatoo Island Dockyard became the lead shipyard and in February 1940 laid down the first ship, HMAS Bathurst. Seven other yards were involved in Queensland, New South Wales, Victoria and South Australia. Of the sixty vessels built, fifty six were commissioned into the RAN and travelled a total of twelve million kilometres during and after the war. The last to leave RAN service was HMAS Waggain 1960, taking with her (to the best of the author’s knowledge) the last Up and Downer in the fleet. Only two examples remain: HMAS Castlemaine is a museum ship in Williamstown, Victoria and HMAS Whyalla is a land based tourist attraction in Whyalla, South Australia. If you would like to see a marine Up and Downer in motion in Australia it seems you have limited opportunities. Close to home is the Museum’s SY Ena, but I should point out for the purists that her engine, while still live steam driven, is two cylinder, not triple expansion. To experience a live triple expansion engine you can take a trip on Sydney Heritage Fleet’s SY Lady Hopetoun. More pedestrian but larger examples are our own from the 1926 Sydney vehicular ferry Kara Kara, and in Melbourne you can visit HMAS Castlemaine. Sadly neither is steam powered any longer.
Footnote: See www.hmascastlemaine.org.au for a good description of this Bathurst class corvette. As explained above the engines were sourced from existing local manufacturers, in this case Thompsons Engineering and Pipe Co. Castlemaine, Victoria.