Diesel Engines

Pictured is Mirlees KV12 Major....similar to the earlier engines I worked on at Peel Power Station

Since I mentioned that I worked on and maintained heavy diesel plant, perhaps some of the more technically minded of my readers may be interested in a few facts about them. The last engines I worked on were Mirrlees MB 430 Vee 16 cylinder, twin turbo charged dual fuel engines .

I have also worked on older engine sets....Mirlees KV 12's, Ruston V 16.'s with high level, chain driven camshafts [ they were a beast ] and Mirlees straight 8's. The Mirlees V's had the normal layout of two con rods to a single crankshaft journal. The Ruston was a different animal altogether. One main rod with a slave rod fitted to it through a wrist pin. . This one big end per journal layout reduced the length of the crankshaft with a correspondingly reduction in overall engine dimensions and increased rigidity. All these engines were so large you had to climb inside the engine to work on mains and B.E.'s. I was responsible for all turbo charger maintenance in my years at the Peel station. These units could weigh up to ton .

The Brown Boveri T/C's on the MB 430's were mounted off engine , in an accoustic housing with two level access. The accoustic housing was necessary as the blowers tend to scream a bit at full boost . .... and with intercoolers developed a boost pressure of about 15 bar. A turbo charger is so called as a turbine wheel , driven by exhaust gases turns a compressor wheel, both mounted on a common shaft......bit like a jet engine in an aircraft.

The cylinder bore was 430mm with oil cooled pistons with B. E's and mains running in thin wall shells. The individual, hydraulically tensioned cylinder heads had four valves , the exhaust valves being removable in their cages, which were oil cooled. All main fasteners were hydraulically tensioned . The fuel injectors were also oil cooled and the heavy fuel the engine burnt was preheated to about 200F. The 11 ton crankshaft was under slung and with gear driven camshafts the whole shebang had a governed engine speed of 600 RPM....plenty fast considering all that metal whizzing around . There was a direct drive to a Brush alternator which pushed out A.C. at 11,000V which transformed to 33,000 V for transmission . If I remember correctly the engine /alternator unit weighed in at about 200 tons and sat on a 400 ton concrete bed which was below engine room floor level and this in turn sitting on banks of heavy coil springs to dampen out vibration. . There were five engine sets in this one engine room which was accoustically sealed. Tremendously noisy inside.....not a sound to be heard in the corridor outside.

Of course there was not only the engines to maintain ....there were a multitude of auxillary equipment to look after. Dozens of pumps, air compressors, filters, fuel modules, fuel and oil centrifuges and many more pieces of plant . Quite a job !!

Ok, you can put your spanners away now.