Raising Steam Naval Instructional Film A76

[Music] particle his majesty's destroyer jovial after a strenuous period of active service has been in for a boiler clean now the job's done she's ready to sail again funnels are covered boilers are cold but soon steam must be raised stores equipment on all the hundred and one necessities of a fully commissioned ship are brought aboard not forgetting a good supply of ammunition just in case hello who's this a wren dispatch rider it's a signal for the captain so the officer of the day takes it below to his Shore cabin go ahead signal from captain data echo Stella chief I want to please Python come in how soon can you race team take about five hours we're cold sir following the orders to raise steam the watches order below two men are detailed to uncover the funnel and so they enter it by a small door at deck level and climb to the top by the iron letter which runs up the inside funnel guys have to be slackened why to make a launch for the expansion when the funnels get hot this gives us a good idea of the required slackness when the cover is removed its rolled up and lowered to the deck to be stowed away here is the layout of a destroyer as regards those departments affected in raising steam routine the steering compartment the boiler rooms numbers 1 & 2 with their auxiliary pumps etc the engine room with auxiliaries and main engines whose gearing at the aft end protrude through the bulkhead into the gear room where two are the oil circulating pumps and last the tiller flat containing the steering gear and rudder head to the uninitiated a boiler room just looks a maze of pipe steps and valves so let's get a clear idea of what it's all about an admiralty 3 drum boiler consists of an upper circular steam drum connected to two lower water drums by nests of tubes the hole forming a letter a super heaters with their tubes are fitted between the outer and inner row of tubes on each side of the boiler we'll deal with them later the triangle between the nest of tubes forms the furnace space now come into the lab and see the elementary principle we have a top and a bottom glass vessel connected by two glass tubes to form a continuous circuit the whole system is filled with water colored water in the bottom flask to make our little demonstration more clear just imagine the glass tubes are boiler tubes the inner one nearest the fire the top flask is our steam drum the bottom one our water drum when heat is applied to the inner tube the heated water rises forming steam in the top vessel or steam drum the water in the steam drum descends through the outer or cooler tube down to the bottom or water drum and so we get a continuous circulation and with that in mind let's get back to our drawing note the water level in the steam drum is normal as when steaming but when idle it should be kept full to prevent airlocks or corrosion the water descends through the tubes farthest from the fire into the water drums then it rises through the tubes nearest the fire during which course it's converted to steam and goes into the steam drum at this stage it's saturated or moist steam so it passes into the super heaters which are out of contact with water in the boiler here our steam is just simply cooked and becoming dry steam passes onto the engines this model boiler with casings on one side removed gives us a perfectly clear idea of the super heater layered it's tubes remote from water are a unit on their own running between the boiler tubes for their full length and depth engine efficiency depends upon limits of temperature high when the steam enters low when it leaves hence super heating which raises temperature without pressure increase and saves fuel for less steam is required and being dry causes no corrosion here's the front view of our boiler study steam and water drum boiler feet air cones with oil fuel sprayers in the center the funnel uptake observation window to see what's happening inside the furnace smoke making nozzles through which an overdose of oil is passed on orders to make smoke here's what happens looking through the observation window and here's what comes out of the funnel but remember a well fired furnace should show no smoke whatever only a heat haze let's take one half away the furnace chamber has to withstand a temperature of 2700 degrees Fahrenheit so it's lined both floor and side tables with courses of brick which won't melt or decompose water to the main drum is fed by an internal feed pipe an automatic feed device controls the quantity of water which passes through a non-return feed check valve note the position of the internal steam pipe through which the steam passes to the super heaters such doors provide access for cleaning purposes and moveable panels provide ready access to the tube nest for boiler cleaning in this sectional drawing we see the outer casings of our boiler in position on one side these cases serve to retain the heat and to act as the necessary conduits for the entry and flow of air and just round things off let's put the other side back and there's the boiler complete and so with the principle fully in mind let's return to the ship for steam has to be raised in five hours and there's no more time to play about with pretty drawings there's a job to be done this is all bills as it were for the bilges like the furnaces have to be examined and kept clean and free of oil if oil is found there is danger of fire and well we all know what fire at sea means so safety first and it's part of the routine to make quite certain that fire appliances are all in good trim now for the fans which supply the forced draft for the furnaces there are not much like the bellows of a great fire but that's their function they run at a very high speed so it's important to see that the oil levels are well up they are checked by a dipstick just the same idea as on a motor car or lorry engine now beer won't flow from a barrel unless you open the vent the same applies here our on the steam drum and superheater headers have been opened so as to release any vacuum which would prevent flow running down hoses are connected to the running down valves superheated drain valves must be open and the steam trap kept on bypass next the running down valves are shut and the valves on the main steam ranges are opened and shut hand tight to make sure that all is working nice and freely fuel oil has a very high flash point here's a crucible of ordinary fuel oil cold all at atmospheric temperature put a light to it and it just won't burn well that doesn't see much good so we'll warm the oil and try again now it's hot and ignites instantly remember this experiment for that just what we have to do in the ship heat the oil before it will burn in the furnace fuel oil is fed to the furnaces by sprayers here's one cut in half it's really a valve with fine adjustment which delivers the oil in a fine misty spray enabling it to burn easily the sprayers are mounted on the boiler as we see here surrounded by adjustable air cones by which the required amount of air can be regulated to give good combustion if you were inside the boiler here's what the delivery end of the sprayer would look like now to heat our oil a small lighting up sprayer is put in place of one of the main sprayers then a long u-shaped tube is inserted into the furnace and each end of it is tapped in so to speak into the fuel oil circuit a small electric auxiliary pump is started so as to circulate the oil this YouTube works just the same way as the old Primus stove we all know how the tube has to be heated before the fuel can be pumped up and made to burn yes it's just the same thing the fuel passing through the hot tube is rendered combustible the YouTube is so fitted that it just touches the small end of the combustion tube when all is ready a handful of oily waste is put into the cone below the YouTube and the small lighting up sprayer is warmed up and brought into use giving sufficient flame to heat the YouTube and the oil which is circulating through it a small thermometer shows the rising temperature of the oil when a blow of steam issues from the air this one's blowing into what's known as a pig's ear they should be shut the drains on the auxiliary steam range are then shut and valves on auxiliary pumps are opened you all know how a kettle furs up and get scales inside it that's due to impurities in the water so frequent tests are made of the boiler water to ensure purity samples of water are drawn from the boiler into a hydrometer pot the temperature is taken and the water is tested for density with a hydrometer now a further test for salinity to a test tube of water a few drops of silver nitrate are added this water is curved nothing happens but just let's see what would have happened if they'd been salt present a white precipitate appears or brown if there's lime in the water so that's why distilled water should always be used in boilers when there's a sufficient head of steam the main oil fuel pump auxilary feed pump and oil fuel heaters can be warmed through and started not forgetting the fans which provide the air and draft the superheated drains are now changed over to the steam trap from the bypass to avoid wasting steam but instead of blowing it into the air by our atmospheric exhaust we're going to put it through the cooler condense it and use the water to make steam again so we put the closed exhaust onto the feed heaters now the oils hot so we can get rid of our old friend the YouTube lighting up gear to you remember that plan of the ship well now we're in the gear room lubricating oil passes through coolers which retain it at the correct viscosity or thickness so all Inlet and discharge valves on the coolers are opened next the forced lubrication pump is started and the lubricating oil circulation checked circulation can be watched and checked at various points by these small glass Telltale's at the aft end of the turbines there's a hand turning gear used to keep the engines free when the ship's laid up when raising steam the gear is disengaged otherwise it might cause serious damage so it's removed and taken to the engine room unless it was there no engineer would start the engines talking of engines let's study the principle of the turbine for it's so enclosed we can't see much in the ship a casing or state as it's called encloses the rotor a cylindrical drum mounted on a spindle in both stator and rotor are set circular rows of blades steam is admitted at one end of the turbine and travels between rotor and casing as it expands between the rows of blades it causes the rotor to revolve the turbine is mechanically superior to any known steam engine but there is only one moving part the rotor and only two wearing services the main bearings to ensure an expansion and normal running conditions before the turbines have started they should be drained and warmed through this man's underneath the turbine opening the drains the turbine is very finely and sensitively adjusted so during the warming through the even expansion of all parts is of vital importance careful observation of movement is maintained throughout and readings are taken from the scale finger plates in high-speed machinery such as a turbine care and attention to lubrication is a matter of paramount importance always remember oil is cheaper than repairs warming through should leave the inlet to the low-pressure turbine at approximately 160 degrees Fahrenheit an hour after steam first shows this thermometer enables the patient's temperature to be watched carefully now the extractor pump is started up and the condenser water level should be watched at the same time well things are now nearly ready Valve's on the closed feed system up to the main feed pump are opened also the error ejector the vacuum is worked up to 20 inches using a minimum of steam for the lower the pressure at the exhaust end of the turbine the greater the efficiency because the work done by a given quantity of steam depends upon the difference of initial and final pressures that is boiler pressure and condenser vacuum part of the routine in raising steam is to test the Telegraph's and steering gear in the steering compartment the engineer officer carries out these tests taking careful record of the readings on the graduated arc which shows the degree of rudder on the ship simultaneously an artificer and the tiller flat is recording the readings from the graduated scale on the receiver crosshead the two sets of readings must correspond exactly you next the revolutions telegraph is rung down to the engine room where the readings on the indicator must correspond with those of the transmitter the maneuvering Telegraph is also tried out in the same way and now everything is ready for see the chief engine room artificer reports and asks permission to try main engines of the officer of the day who first make sure that all lines and obstructions are cured of the propellers all scare so the chief engineer tries out the main engines the ahead and astern maneuvering valves are worked moving the engines a few revolutions ahead understand in fact this performance is repeated every few minutes keeping the engines warmed and drained until required for use that won't be long come in engines ready for you sir good bring on ring on syrup let go pull it the red ball go ahead Porter are they had both one three revolutions [Music] and so to see just over four hours ago hms jovial lay alongside a lifeless ship now throbbing to the rhythmic power of her engines she moves to sea on another of her many duties [Music] [Applause] is

Channel: CV-12 Docents

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Id: twA21fxiMDI

Length: 21min 11sec (1271 seconds)

Published: Mon Aug 14 2017