Rolls-Royce Merlin Engine

[Music] when in 1938 war clouds were gathering over the continent of yada the rolls-royce factory and are they assumed a new importance home of the company since its inception in nineteen six it was from here that one of the United Nations greatest contributions to victory was brought to fruition by a picked group of designers engineers and executives under the able leadership of Sir Arthur Syd grieves and mr. e w Hines inspired by the tradition handed down by the late Sir Henry Rice that only perfection was good enough management and workers set about the task of further developing a narrow engine which would enable the air forces of democracy to sweep the enemy from the skies and bomb his industries into submission this engine was the Merlin away from him in danger of air attack an unobtrusive country house set deep in the Derbyshire countryside sheltered the rolls-royce aero planning department here engine designers worked under conditions of highest secrecy on the development of the merlin engine armed with data and experience gained from previous engines the main characteristics of the new engine had already been decided in theory by the engine development committee at Derby and now began the task of calculating main dimensions and producing the plans for quantity production at the same time scale models of complete engines and power plants were made of wood in order to visualize and check the exterior dimensions while much time to be saved in checking the dimensional suitability of modifications matters like frontal area engine weight working of retractable undercarriage position of centre of gravity could all be deduced from measurements and behaviour of these models next step was the making by skilled engineer draftsman of many thousands of detailed working drawings which would constitute the basis for building the prototype as these drawings had in turn to be duplicated for use in the workshops a blueprint department with an average output of 6,000 drawings a day was brought into being at the experimental shop in Dobby emphasis is on the man rather than on the tool versatility is the key net every job is different and the men in this shop are among the most skilled workers in the rolls-royce organization soon the first components begin to take shape in the experimental shop the tool equipment is less specialized than that of the factories on production work as it is concerned men there with one-off jobs where duplication is necessary for parts like connecting rods a killer machine is used the cutters are made to follow a master template producing several identical pieces at a time few jigs and fixtures are available in the experimental stage so the alignment of a machine surface is checked on the marking off table a new engine is seldom built compete at first so that although the production engine may have 12 or 24 cylinders the first experimental job may only consist of one section of the crankshaft and from this single cylinder engine comes the first positive information from these results a forecast of the behavior of the full-size prototype can be made when the prototype is assembled it goes to the test house the engine is coupled to a dynamometer which is a form of water brake which absorbs the entire power output of the engine and is capable of adjustment so that the characteristics of the engine are different loads and speeds can be measured the control panel also has internal consumption boost pressure oil pressure coolant temperature engine revs power output and many other quantities ever since it was first developed the rated horsepower of the Merlin has steadily increased the later types have a power output two or three times as great as that of the original prototype without any great change in leading dimensions after test the prototype is stripped down and its parts are subjected to minut inspection parts which show signs of undue stress or wear are examined by the chief engineer and designers who decide what alterations in design manufacturing methods or materials are necessary once the prototype has passed its first test bed trials it undergoes further tests with the air screw fitted finally it is ready for its flight test installed in an aircraft fuselage the rolls-royce test pilot takes off to confirm that the Merlin engine will in practice do as much and even more than the designers had planned realizing that quantity as well as quality would be the need of the day the Air Ministry asked rolls-royce to build a large factory away from Darby for the quantity production of Merlin engines in 1938 work began on the erection of a large ultra-modern plant at Crewe while in 1939 as war became a certainty the company were asked to build yet another factory about twice the size of Crewe Glasgow was selected and work commenced on the Glasgow plant in July 1939 by early December the first machine tools were already in production on the Merlin in laying out the various factories for quantity production the problem of the most efficient placing of machines and processes were solved by making plans silhouettes to scale of each machine and item of workshop furniture these silhouettes were then maneuvered on a scale floor plan until the ideal disposition was found the layout was then photographed and copies were sent to the plant engineers as soon as all the machines were installed full-scale production on Merlin engines commenced producing the merlin engine in vast quantities without losing anything of the world-renowned rolls-royce qualities of precision workmanship presented untold obstacles apart from the difficulties of operating under wartime blackout conditions and the demands of the fighting services on road and rail transport making difficult the movement of raw materials there was the problem of labour to overcome the manpower difficulty training establishments were set up in various parts of the country under the tutelage of skilled rolls-royce craftsmen both men and women were given intensive training in the operation of highly specialized machine tools in a section of the factory especially equipped for this purpose in order to increase the supply of engineering draftsmen experiments were made in training women of suitable educational qualifications inspired by the firm's tradition these women eagerly proved their aptitude for this exacting work and large numbers graduated to works drawing offices at the various plants apart from training men and women for error engine production the company was faced with the problem of housing and transporting them to and from work at Birth Crewe and Glasgow housing the states and hostels were built within sight of the plant to shelter the workers who had come from all over the United Kingdom in view of the fact that in Glasgow alone over 1500 houses had been built the local transport companies were called upon to cooperate in organizing 126 special bus services to and from a Depot inside the works itself enabling the workers to get immediate transport to outlying districts to protect the factories against air and ground attack strong home guard and civil defense detachments were formed made up of volunteer workers from the various plants Fire Brigades also manned by workers soon reached a high degree of proficiency and were equipped with motor pumps and all the latest firefighting appliances the Rolls Royce organization was possibly unique in having its own bomb disposal unit equally prepared to play a vital and dangerous part in an emergency in order to safeguard the workers health an efficient medical organization was brought into being all new workers were given a medical examination and eyesight test while surgeries and restrooms staffed by resident doctors and nurses were a feature of each plant in order to ensure maximum cooperation between workers and management joint production committees were formed at each Factory consisting of representatives of the management and representatives and shop stewards of the workers vast stocks of raw materials were built out and a sample of every piece of incoming bar tube rod or forging was sent to the laboratories for analysis each batch of material was given a number which stayed with it through every process and a sample was taken so that a fault developing at any time during the components history could be traced back to the raw material stage some of the most valuable raw materials were the light metal and other alloys discovered and developed in the company's research laboratories at Derby apart from the famous are our 50 used in the manufacture of castings many other equally important contributions to the Allied war effort were made by the pick of scientists and technologists working in these laboratories in the rolls-royce drop-forged shop alloy steel forgings were pounded out night and day the most highly stressed components of the merlin engine are made from these four genes which allow a very high output of accurately formed parts while the metal itself due to its molecular flow under the blows of the forge becomes more homogeneous and capable of withstanding higher strains from the manufacture of the Merlin engine the light alloy foundry at Glasgow is unique in the rolls-royce organization and probably in the world the foundry with its core molding and fettling shops occupies two entire blocks of the factory and is organized like the rest of the plant on a flow of production bases the layout of the foundry and its organization for production constitute a great feat of technical planning every kind of casting used in making Merlin engines is produced here very many difficulties had to be overcome on the material side of the process and the achievement is made more remarkable by the fact that many of the workers are trainees a large proportion of them women core making is a process which illustrates the way in which complex operations normally requiring much time and a high order of skill have been rendered reffered and certain in the hands of trainees of both sexes the latter cores are made by hand and men led by women on corps tables to which ready mixed sand is delivered by an overhead conveyor system all the 300 odd intricate cores which go to each engine are made in the same manner organization has made each individual job simple men make the heavier caused by machine a number of heavy cores are used in the upper half of the crankcase mold to form the bearing webs this is one of the two main welding bays which are arranged on either side of the line of furnaces the molding machines are mostly of the rollover job type both hydraulically and pneumatically operated and very simple to control this mold for the upper half of the crankcase is the largest on the engine compete with cores and molding box it weighs a ton the number of cores in the world are an indication of the intricacy of the casting this mold of the upper half crankcase although the largest is by no means the most intricate in the engine the aluminum alloy principally of the famous are our 50 is melted in gas heated tilting furnaces adjacent to the mill conveyors the larger molds are poured from two sides simultaneously this allows the use of ladles of manageable size and also tends towards an even temperature of metal throughout the mill that in many and very large Rises are employed to ensure sound metal in the casting castings are fiddled in this Bay with power saws and pneumatic hand tools the first job is cutting off the runners and risers on large castings these are very massive and a special type of twin hand circular saw has been developed to do the job the saws cut into the surplus metal from both sides so that it can be easily broken away at the end of the cut final fettling of the castings is done with pneumatic chisels these cut away all the flesh and webs which are not needed in the finished casting every casting is inspected before it goes for heat treatment before the castings are machined they undergo heat treatment in this 88 feet long priests furnace the castings are loaded onto bogies which are pushed into the front end of the furnace this automatically pushes out to completely heat treated load at the other end it has three heat zones and the temperatures are automatically regulated within plus or minus two degrees centigrade very many Merlin castings are produced by die casting metal molds or dyes are used in this process which thus effects a considerable saving of time since the same mold can be used over and over again the die castings are taken away on the conveyor for heat treatment in the same way as sand mold castings these die castings can be made to much final limits than can ordinary sand castings the surface is smoother and because no gases are evolved in the mold the metal is usually more homogeneous the casting has go to the machine shops for finishing during the last few decades amazing progress has taken place in the development of very elaborate and complex machine tools both automatic and semi-automatic even in the hands of trainees or unskilled operators these machines can and do perform the apparent miracle of producing in vast quantities the most intricate parts with the highest degree of precision actually many men and women classed as unskilled or semi-skilled have become highly skilled and proficient in working a particular machine or operation but the term is still used to distinguish them from the fully skilled rolls-royce operator operators such as those at the Derby works have served a long term of apprenticeship and schooled in the rolls-royce tradition qualified by this skill and experience to set up in a machine and make the many adjustments necessary to keep it producing accurate work in the hands of trainee operators many of these machines have actually been developed by rolls-royce engineers and such as the final simplicity of operation that although a skilled man would need vast quantities of complex drawings to make the parts by hand these company developed machines can be handled by comparatively inexperienced trainees while still retaining the rigid rolls-royce standards of precision the crankshaft is probably the most highly stressed component of an aero engine over 140 separate machining operations are needed to produce the merlin crankshaft for these processes a large number of special purpose machines were developed by Rails rice including vertical and horizontal automatic lathes deep drilling and grinding machines and these crankshaft letting machines the rough crankshaft forging weighs 250 pounds in its finished condition the shaft weighs a hundred and eight pounds the connecting rod is another highly stressed component of the engine and over 160 operations are necessary to produce a completely articulated pair now after every machine operation on a rails rice component the part is subjected to careful inspection before passing on to the next operation women proved themselves to be particularly adept at this exacting work there are over 11,000 parts in a merlin engine and a high proportion of the smaller items are made from bar material an automatic and capstan lathe except for tool setting this work is repetitive though quite an amount of skill is needed to be a good operator nevertheless they consistently high output figures on close limit work to rolls-royce standards achieved by a trainee men and women who previously had no experience in the engineering industry is indeed a remarkable achievement some 90 different types and sizes of gear wheels go into the Merlin and all must be produced to exceptionally high standards of accuracy accurate tooth form and perfect structure of the metal itself is vital to the smooth running of gearing a special gear analyzer is used for measuring the tooth forms of helical gears this apparatus traces an enlarged graph showing any departure from the theoretically perfect form great care and thought were diverted to the development of valves and valve springs machines from forgings the first valve forming operations are done on turret lathes and automatics the heads and seating faces are covered with a special heat-resistant nickel chrome alloy applied in the flame of an oxy-acetylene glow lamp exhaust valves are made with hollow stems and are half filled with sodium which melts at a low temperature when the engine is running heat is transferred from the head of the valve to the stem via the sodium splashing up and down valve springs are made from coils of high tensile steel were in a specially designed machine which coils valve springs continuously and automatically accustomed to length after grinding and finishing the springs are tempered in a special furnace the journal and begins of the Merlin run in bearings of a lead bronze alloy the bearing shells are made of steel into which are inserted casting tubes secured by spinning the lower edges over in a lathe after the shells have been preheated the lead bronze alloy is cast from a parametrically controlled electric induction furnace the poured liners are then placed in a special cooling device consisting of a cylinder with jets of water spraying inwards the rotor of the supercharger is outstanding among the light alloy components of the engine this component may be called upon to run at between 20,000 and 30,000 revolutions per minute corresponding to a peripheral speed exceeding the velocity of sound it is therefore in the highest degree important that this rotor should be perfectly balanced this is achieved by machining it all ever there are countless machining and finishing operations involved in the manufacture of thousands of other Merlin engine components to each of these unstinting thought and care were given in devising machines and machine tools capable of producing the required rate of quantity output without losing anything of the traditional rolls-royce quality in order to ensure that the standards of manufacture were being maintained rolls-royce engineers developed many high precision measuring gauges and other complicated items of inspection apparatus to augment and improve the standards of normal engineering precision gauges inspection of each of the eleven thousand Merlin components not once but many times was continuous throughout every stage of manufacture including a thorough a final inspection when the parts were completed every factory has at least one air-conditioned temperature controlled standards room in which the gauges and inspection devices used in the manufacture of rolls-royce engines are continually checked against standard gauges and position comparators whose accuracy is of the order of ten millionths of an inch when the finished components reached the sub-assembly stage the engine begins to take shape the assembly process is arranged as a sequence of operations in the same way as the machining the sub assembly benches are arranged in lines between the finished parts stores and the engine direction lines the component travels along the assembly line through the hands of dozens of different workers who each add their part or do their particular operation so that the component is finished at the end of the line components like the supercharger are built up separately so that they go into the end has complete units at the end of the sub assembly lines is the engine assembly shop where the sub assemblies are delivered at convenient points and are put together to make complete engines engine assembly starts with the crankcase which has had all its studs and cylinder holding down both fitted on the sub assembly benches the engine assembly line has a bench height rail track down the center which enables the work to be pushed easily from station to station along the line a turntable in the track at each siding enables the engine to be run off the main line while fitting is in progress leaving the main line free for the flow of work at each station a sub assembly or component is added to the engine as the engine passes down the line it gradually it takes for the policy of specialization is applied here in the same way as in the other departments of manufacture each job is done by a cruel who are specialists in fitting their particular component this policy enables the workers to become expert in a short time at the end of the line the completed engine is vetted by an inspector who notes the numbers of individual components and assigns a new number to the whole engine from now on it has an identity it is given a logbook in which all its subsequent history will be recorded but meanwhile it is to be taken away for its first run on the test bed every Merlin is run on the testbed before it is passed into service the Ministry of aircraft production prescribed very stringent tests for engines to be used in the RAF or the effete Air Arm so several hours run at the rated horsepower of the engine are followed by bursts of maximum power while test engineers make careful notes of the engines behavior a certain proportion of engines which have satisfactorily passed their tests are nevertheless brought back and immediately stripped down the running test demonstrates that every component is capable of doing its job this stripped down is to make sure that there be no overheating or overloading and to ensure in short that the engine will go on doing its job and maintain the standard of manufacture once more reassembled the engines are ready for active service but the job is not yet finished just before the war it became apparent that in order to ensure the satisfactory installation of the engine and the consequent safety of the airplanes crew it was necessary for rolls-royce to divert their engineering skill to designing the completely cowled powerplant installation ready for attachment to the airplane fuselage this enterprise in tackling the complete power plant and developing it into a quickly detachable an interchangeable unit was acclaimed as one of the outstanding achievements of British aviation during the war no survey of rolls-royce wartime service would be complete without reference to some of their many other contributions to the success of the Allied nations early in the war it became obvious that the facilities which had been envisaged for the repair of damaged engines were going to prove entirely inadequate and measures to remedy the position became of the utmost urgency rolls-royce set about tackling this problem and had the satisfaction of seeing the figure of overhauled engines which stood at a few hundred in 1939 rise to over 18,000 during 1944 the Rolls Royce school of instruction at Derby had trained nearly 17,000 people in the use and maintenance of rolls-royce engines and other products there's trained included pilots flight engineers and ground personnel of not only the Royal Air Force and the Fleet Air Arm but of representatives of the air forces of most of our allies another interesting example of rails Royce versatility were the development of a small-caliber 40 millimeter quick-firing gun for use in mtv's and similar craft the merlin engine was also adapted for powering these high-speed motor boats then again there was developed a modified and unsupervised the meteor which was used to power the first prototype of a new tank the effect of the extra power of the engine on the prototype tank was such that rolls-royce engineers were tasked to collaborate in developing the tank itself the fruits of this collaboration resulted in the famous Cromwell tank which covered itself in glory on the dash from the Normandy Beach heads to the Rhine the rolls-royce organization may well be proud of its contribution to the co-workers designers engineers management all fulfilled a vital role in Britain's days of NEET now they can once more turn their hands and their brains to the fulfillment of the needs of a world of peace and this indeed they have done for in October 1945 two months after the end of hostilities it was a rolls-royce jet turbine that strict across Britain's larung skies to claim the world speed record of six hundred and six miles an hour what promises to Civil Aviation did this imply what even newer principles of engine design and propulsion are now occupying the minds of the rolls-royce organisation for the world of science has much in store and in the forefront of mankind's March onward will be a rolls-royce applying to practise the newest and latest principles of scientific achievement [Music]

Channel: King Rose Archives

Views: 1,662,704

Rating: 4.8463893 out of 5

Keywords: Rolls-Royce Merlin (Aircraft Engine Type), Rolls-Royce Motor Cars (Organization), Battle of Britain, Supermarine Spitfire (Aircraft Model), North American P-51 Mustang (Aircraft Model), World War II (Event), Aviation (Industry), Automobile (Industry)

Id: -fo7SmNuUU4

Length: 28min 8sec (1688 seconds)

Published: Fri Apr 25 2014

Reddit Comments

[u/FigMcLargeHuge]

Loved it. Thanks for posting that link.

[u/bfbabine]

Today, it costs about $100K to overhaul a Merlin engine!