Kyösti Kylälä

Kyösti Kylälä (born Gustaf Georg Adrian Byström; 16 August 1868 in Salmi – 15 August 1936 in Viipuri^[1]) was a Finnish railroad engineer and self-taught inventor. In 1919 he patented in the UK an 'Improved means for increasing the draught in steam boilers, especially on locomotives.'^[2]

Kylälä's invention, sometimes known as the 'Kylala spreader' involved the insertion of four nozzles in the blastpipe of steam locomotives. The system was originally devised to reduce spark-throwing and later it was claimed that there was a more even draught over the tubeplate and that the need for tube-cleaning was reduced.^[3] It was tried out in 1922 by Lawson Billinton on a LB&SCR K class locomotive, but with only limited success.

Later the French engineer André Chapelon, developed and improved the invention by using a second-stage nozzle and adopted the name Kylchap for this design. Kylchap exhausts are found on many French and British locomotives notably the Flying Scotsman and the world record holding Mallard.^[4][5]