The New Zealand Railways Magazine, Volume 6, Issue 7 (February 1, 1932.)
History of Superheated Steam — The Trend of Modern Development
227 Years of Progress.
Experiments in the production and application of superheated steam can be traced back as far as the year 1705. It is, to-day, universally recognised, however, that Dr. Wilhelm Schmidt, of Kassel, Germany, whose investigations extended over a period of forty years, is the pioneer of practical superheating.
In 1898 Dr. Schmidt started the commercial application of superheaters to railway locomotives, the first superheated engines being placed in service on the Prussian State Railway. It is from that date that the practical history of superheating commences.
Early locomotive superheaters, which were of the smoke-box type, achieved only a moderate degree of success, the total number of engines fitted being less than 150.
In 1902, however, Dr. Schmidt introduced his Smoke Tube Superheater, which proved so successful on the Continent, that, in 1908, the Schmidt Superheating Company, Limited, was formed for the purpose of developing the use of this design in Great Britain.
In 1910 the progress which had been made by Dr. Schmidt in Europe resulted in the formation of The Locomotive Superheater Company (now The Superheater Company) in the United States, in order to develop the use of his apparatus in that country.
The Schmidt Superheating Co., Ltd., was reorganised in 1919, and renamed the Marine and Locomotive Superheaters Ltd., and, finally, in 1924, after amalgamation with the Superheater Corporation, Ltd., assumed its present title of The Superheater Company, Ltd.
In the early days of practical superheating only moderate final steam temperatures were employed, particularly in the case of Marine and Stationary Reciprocating Engines, about 550 deg. F. being the maximum temperature in this class of work.
In the case of locomotives, temperatures were somewhat higher and, for a time, progress in superheating was largely confined to this field.
The introduction of the turbine gave a further great impetus to the use of superheated steam for Stationary Engine work and the advantages of higher final temperatures were recognised.
This demand for higher superheat has persisted, and, at the present time, the use of steam at 900 deg. F. is proposed in one or two large plants now under construction; while a number of plants are in actual operation with steam temperatures exceeding 800 deg. F. at the superheater outlet. In locomotive and marine work there is a similar trend in development.
In addition, higher steam pressures are also being employed, and at the same time revolutionary changes in boiler design and methods of firing are taking place.
The Works of the Superheater Company, Limited, were built in the year 1914 and, from the outbreak of the War, were engaged on the production of munitions as a controlled establishment until 1918. They are situated in Mosley Road, Trafford Park, Manchester, close to the Ship Canal, and with easy access to the main Manchester-Liverpool Road. Private sidings give direct communication with the L.M.S. and L. & N.E. Railways.
The main buildings consist of 5 parallel bays 240 feet long, which are all under one roof, and cover an area of over 70,000 square feet. Each bay has overhead page 64 cranes up to 5 tons lift. In addition there is a gantry serving an uncovered area. Electricity obtained from the Stratford Corporation Electricity Department is used for driving the major portion of the plant. There are also Reavell and Ingersoll Rand air compressors, a hydraulic accumulator plant maintaining a pressure of 1,250 lbs. per square inch in the mains, with an intensifier for pressures up to 3,500 lbs., and an acetylene gas generating plant. Air pressure to furnaces is supplied by Sirocco and Sturtevant blower fans.
The plant in No. 1 Bay consists of Tool Room and Machine Shop, while Nos. 2, 3 and 5 accommodate the special plant which is employed in the manufacture of the “M.L.S.” integrally machine forged Return Bend Superheater Elements for Marine, Locomotive and Stationary Boilers respectively. No. 4 Bay is used for Stores and Despatch.
The Forging Plants, of which there are three complete sets, are of considerable interest, there being nothing similar in Great Britain.