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GIFT OF 
 Arthur E. Moncaster 
 
Small Turbines for 
 Electric Drive 
 
 A description with 
 
 suggestions and instructions 
 
 for their 
 
 INSTALLATION 
 
 CARE AND 
 
 OPERATION 
 
 ENGINEER'S REFERENCE BOOK 
 
 Please keep this book where your engineer can refer 
 
 to it readily 
 
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Instruction Book WM 105 
 
 Jan. 1913 
 
 The Westi n^house 
 
 Small Turbines for 
 Electric Drive 
 
 A description with 
 
 suggestions and instructions 
 
 for their 
 
 INSTALLATION 
 
 CARE AND 
 
 OPERATION 
 
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 INTRODUCTORY 
 
 The following pages describe the small turbines manu- 
 factured by The Westinghouse Machine Co., and are in- 
 tended as a guide for those who have occasion to erect and 
 operate them. The matter herein is confined to a detailed 
 description of the construction together with illustrations. 
 It is believed that a better knowledge of the operation of the 
 machines may be imparted in this way than by a lengthy 
 series of instructions. 
 
 The particular type of turbines herein described, is 
 intended for direct connection to small direct current or 
 alternating current generators, in sizes from one to 300 kilo- 
 watts. The smaller sizes are designed for non-condensing 
 service only, while the larger units are built for either con- 
 densing or non-condensing 'operation. 
 
 Full instructions covering the direct and alternating 
 current generators connected to these turbines may be found 
 in the following publications of The Westinghouse Electric 
 &Mfg. Co.: 
 
 D. C. turbo generators, Instruction Book 5107. 
 
 A. C. turbo generators, Instruction Book 5024. 
 
FUNDAMENTAL PRINCIPLES OF SMALL WESTING- 
 HOUSE STEAM TURBINES. 
 
 As in all steam turbines, the operation depends upon 
 the expansion of steam in suitably formed nozzles so that the 
 potential energy given up during the expansion causes the 
 velocity of the expanded steam to increase the velocity at 
 the outlet from the nozzle or nozzles being such that the 
 kinetic energy (velocity energy) is substantially equal to the 
 energy given up during the expansion in the nozzles. After 
 the expansion in the nozzles, and having converted the poten- 
 tial energy in the steam into kinetic energy, means must be 
 provided for converting the energy of motion into mechanical 
 work at the shaft. This may be done in a number of different 
 ways, and the method employed in the small turbines under 
 discussion depends almost wholly upon the operating condi- 
 tions, though it is also governed partly by the size of the 
 turbine and the shaft speed. 
 
 To show more clearly the differences found in the 
 working parts of the smaller turbines, the diagrammatic 
 sketches Figs. I, 2, 3, 4 and 5 are presented. The principle 
 involved in all of these is the same, differing only in degree 
 of elaboration as higher powers and higher pressure ranges 
 are reached. 
 
 The arrangement of Fig. i is the simplest, consisting of 
 only the nozzle "A," a single row of rotating blades "F," and 
 the reversing chamber U B," which parts are common to all 
 small turbines. Steam is admitted to the nozzle "A" through 
 the governor valve, and expands to approximately atmos- 
 pheric pressure, thereby attaining a velocity which is about 
 four times the velocity of the moving blades in Fig. I . Now 
 since the blades move with about % the velocity of the steam 
 leaving the nozzle "A," the steam after having passed through 
 the moving blades, enters the reversing chamber "B," with 
 approximately half the nozzle velocity. 
 
 The reversing chamber "B," as the name suggests, 
 reverses the direction of the steam, and causes it to again im- 
 pinge on the same row of moving blades, further reducing the 
 velocity of the steam, and thus absorbing the energy remain- 
 ing after the first passage through the blades. 
 
 In the arrangements Figures 2, 3 and 4, the principle 
 of operation is the same as for Fig. I, except that instead of 
 completing the expansion in the first nozzle, the expansion is 
 carried down only sufficiently far to give the steam the desired 
 velocity, i. e., approximately four times the blade velocity. 
 
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The expansion is then completed in a second nozzle "C" 
 (Fig. 2) after which the steam passes through the blades a 
 third time, enters the reversing chamber "D," passes through 
 the same row of blades a fourth time and thence to the ex- 
 haust. This may be regarded as a combination of two of the 
 elementary units shown in Fig. i, in the same manner as two 
 cylinders of different sizes are put in series to form a compound 
 engine. Thus, by a proper selection of one of these arrange- 
 ments, the turbine can be adapted to any steam pressure and 
 blade speed. 
 
 Fig. 3 shows a nozzle arrangement for a condition 
 intermediary between Figures I and 2, in which the steam 
 makes one passage through the blades after passing the second 
 nozzle. 
 
 Fig. 4 is a combination occasionally used, in which the 
 element in Fig. i is followed by two nozzle elements, each dis- 
 charging steam once through the blade passages. 
 
 Fig. 5 shows the scheme used in some of the larger 
 turbines to permit carrying heavy overloads, or temporary 
 operation with low steam pressure. Steam from the governor 
 valve is admitted to the nozzle "A" same as in Fig. i, but in 
 addition a secondary hand operated valve admits steam to the 
 nozzle "E," which is also under the control of the governor 
 when in operation. It will be noted that the nozzles "A" and 
 "E" each have an independent reversing chamber, that for 
 the nozzle "E" being located within that for the nozzle "A," 
 thus utilizing the energy in the steam with equal economy at 
 heavy overload, as well as at normal rating. 
 
 The overload valve "E" should not be used, however, 
 except when necessary to prevent the speed from falling and 
 lowering the voltage, as then the economy will not be so good 
 at fractional loads. 
 
 General Features of Design. All the turbines, ex- 
 cepting the 10 and 15 Kw. sizes, and smaller, are equipped with 
 a vertical geared governor of generous design, having great 
 power, operating at the best speed for efficient and close 
 regulation. An extension of the governor spindle downwards, 
 operates an oil pump of simple design, for supplying the bear- 
 ings with an ample flood of oil. 
 
 Fig. 6 is a typical cross section of a small turbine, and 
 shows also on the end elevation, the automatic stop and 
 governor valves. It will be noted that the rotor carries but a 
 single row of blades, which revolves between the nozzle blocks 
 and reversing chamber, as previously described. These are 
 plainly indicated in the lower portion of the machine. 
 
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All the working parts of the turbine are in the lower 
 half of the cylinder or casing, thus making it unnecessary to 
 disconnect the steam and exhaust pipes when the turbine is 
 opened for inspection. Also, it permits the spindle to be 
 removed from the casing without removing the turbine rotor 
 from the shaft. Furthermore the governor (shown in greater 
 detail in Fig. 15) may be removed from the turbine without the 
 necessity of taking it apart, beyond disconnecting the link 
 attached to the governor valve stem. The governor shown in 
 Fig. 6 is driven by means of a worm and wheel, although in 
 some cases bevel gears are used. 
 
 The oil pump, which is located under the oil reservoir, 
 is driven by the governor spindle. 
 
 This particular design of governor may be removed 
 from the turbine by simply removing the bolts on the horizon- 
 tal joints and upper half of the vertical joint. However, some 
 governors have the union type coupling and cannot be removed 
 until the union coupling has been disconnected, the latter 
 being accessible through the hand-hole shown in the cross 
 section, Fig. 6. 
 
 In the majority of small turbines there are but two 
 bearings, both of which are part of the generator, the turbine 
 rotor being carried on the end of the generator shaft. In some 
 of the larger sizes, three bearings are employed, as also in the 
 case of small turbines for driving alternators. 
 
 Rotor. In smaller sizes up to 25 Kw., the turbine 
 rotor is integral with the hub, but in the larger sizes the rotor 
 consists of a hub to which the turbine disc is bolted, the disc 
 being doweled into the hub to insure its running true. 
 
 The blades, as will be seen from the cross section of the 
 rotor, are held in place by means of rivets which go through 
 the shanks of the blades inserted in the periphery of the 
 turbine disc. 
 
 The hubs of all rotors are fitted on to the shaft with a 
 considerable taper, so that if necessary they can be easily 
 removed by loosening the nut on the shaft and tapping the 
 latter lightly with a babbit hammer. The extension shaft for 
 driving the governor is bolted to the rotor hub and carries the 
 outboard turbine gland sleeve and also the automatic stop, 
 which will later be taken up in detail. 
 
 In 'the case of alternating current units, it is, for elec- 
 trical reasons practically impossible to split the armature 
 horizontally, and therefore it is necessary to withdraw the re- 
 volving field from the armature endwise. For this reason, 
 
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the turbine wheel is doweled and bolted to the governor drive 
 extension shaft, which is in turn doweled and bolted to the hub 
 on the generator shaft. It is necessary therefore, in disas- 
 sembling the machine, to first remove the gland ring "A" 
 (Fig. 6) and remove the bolts "B," which attach the governor 
 drive extension shaft to the hub "C." The revolving field 
 can then be drawn out through the collector end of the gener- 
 ator. The hub "C" should not be removed from the gener- 
 ator shaft unless necessary in order to remove the gland sleeve 
 "B." It will be evident that these fits should be disturbed as 
 little as possible, so as to maintain the rotor running true. 
 
 In assembling the rotor, and all parts of the interior of 
 the turbine, particular care should be taken to ascertain that 
 all wiring and split pins for preventing the loosening of bolts 
 and nuts are in place before the cylinder cover is put on. It 
 is evident that considerable damage might result if a bolt or 
 nut were to loosen and come out while the turbine is in opera- 
 tion. 
 
 Nozzle Blocks, Reversing Chambers and Flexible 
 Packings. In turbines operating on 125 pounds steam pres- 
 sure, or less, the nozzle and reversing chamber arrangement 
 shown in Fig. i is generally employed, and as previously 
 stated, the entire expansion is completed within the nozzle. 
 There is no tendency for the steam to leak out of the blades or 
 reversing chambers, as the pressure in the latter is the same as 
 in the turbine casing. In the other arrangements, however, 
 as shown in Figs. 2 to 5, as the steam is only partly expanded 
 in the first nozzle, the steam is under greater pressure in the 
 first reversing chamber and following nozzles than in the 
 casing. Therefore, it is evident that since it would be an im- 
 possibility to run without clearances between the rotating 
 wheel and nozzle blocks, there would be considerable leakage 
 through the clearances "G" and "F" (Fig. 8), as well as along 
 the space between the periphery of the wheel and the turbine 
 cylinder. 
 
 To obviate the leakages which would occur with reason- 
 able running clearances, a packing shown at "D" (Fig. 8) is 
 employed. This consists of one or more brass strips having 
 a lug "C," which are inserted in undercut grooves turned in 
 the flange of the nozzle blocks and reversing chambers. These 
 brass strips, which are made in sections about 3" long, are 
 pressed against the wheel by small flat springs shown at "E." 
 When first inserted in the machine, the strips are of such a 
 depth that when pressing against the wheel, the lug "C" on 
 
 10 
 
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 11 
 
the strips is a slight amount away from the shoulder "O" of 
 the undercut grooves in the nozzle block and reversing cham- 
 ber flanges. When the turbine is put in operation, the fric- 
 tion of the brass strips on the turbine rotor wears away the 
 brass strips until the lug "C" of the strips engages with the 
 shoulder "O" of the undercut grooves, which prevents the 
 strips from further wearing upon the turbine rotor the latter 
 then revolving between the strips without touching them, and 
 yet practically without any clearance. Thus, though the 
 clearance is reduced to practically nothing so far as leakage 
 is concerned, should for any reason an actual displacement of 
 the rotor occur, the packing strips would simply be pushed 
 back against the springs, and wear away without in any way 
 injuring the rotor or turbine. 
 
 The leakage which would occur between the periphery 
 of the wheel and cylinder is prevented by packings which work 
 on exactly the same principle, but are made in the form of 
 round or square buttons which press against the periphery 
 of the wheel and are shown at "I" in Fig. 8. These buttons 
 are placed at the beginning and end of each stage in the tur- 
 bine, as indicated in the small diagrammatic sketch in the 
 upper part of Fig. 8. In the latter, the steam is under pressure 
 in the space " K " and would tend to leak into the spaces " M " 
 and "L" on the other side of the packings "I." The only 
 difference between the button packings and the strip packings 
 is that the former are pressed against the rim of the wheel by 
 small helical springs, in place of the flat springs employed on 
 the circumferential packings. 
 
 The packings employed require no attention whatever 
 for normal operation, but if for some reason the turbine rotor 
 has been allowed to move axially, it may be found upon 
 opening the turbine and making an examination that the 
 strips on the one side of the wheel have been worn away so 
 that when the wheel is again centralized, the packing strips 
 on one side or the other may not come in contact with the 
 wheel. If this is found to be the case, the packing strips 
 should be removed and the lug "C" scraped away sufficiently 
 to permit the strips to bear lightly against the rotor, which 
 should be adjusted axially so that a clearance of .020" to 
 .025" exists on either side of the rotor, between it and the 
 nozzle blocks. The position of the wheel may be adjusted by 
 means of the thrust bearings as described on page 17, details 
 of which are shown in Figure 13. The position of the wheel, 
 with reference to the nozzles and reversing chambers, may be 
 
 12 
 
H? 
 O 
 
 CO 
 
readily observed through the hand-hole in the cylinder cover. 
 Renewing the packing strips is really a trivial matter. 
 
 All nozzle blocks and reversing chambers are very 
 carefully scraped to a steam tight fit before leaving the shop. 
 As any leakage from the nozzles or reversing chambers will 
 impair the steam economy of the turbine, great care should be 
 taken to insure that the surface between the nozzle blocks and 
 the cylinder casing, (as at "H," Figure 8), is a perfectly steam 
 tight joint. 
 
 The general disposition of the nozzles and reversing 
 chambers, with reference to the wheel, is shown in Fig. 9. 
 
 Glands. In small non-condensing turbines, leakage 
 of steam from the turbine cylinders through the openings 
 through which the shaft passes, is prevented by simple forms 
 of glands shown in detail in Figure 10. As will be noted, the 
 gland consists simply of a number of special bronze snap rings 
 fitted into a cast iron sleeve shrunk on the turbine shaft, and 
 the gland bushing fitted to the turbine cylinder with a steam 
 tight joint, within which the snap rings are fitted. The bush- 
 ing "G" (Fig. 10) is shown in detail. The one point to be 
 noted is the pocket "A," which supplies oil to the space between 
 the first and second snap rings, through the hole "B." Any 
 steam leaking past the first and second snap rings is free to 
 escape to atmosphere through the hole "C," connecting with 
 the space "E." 
 
 A passage "H" is also shown, which connects to a 
 small sight feed oil lubricator, and also a drain passage "I," 
 which should be connected to the sewer or any other conven- 
 ient point outside the engine room. As the pressure within 
 the turbine cylinder will always be greater than that of the 
 atmosphere, there is no chance for the very small amount of 
 oil supplied to the glands to get into the exhaust steam, as the 
 leakage is always outwards. To prevent a small amount of 
 condensation which might leak past the outer snap ring, from 
 being thrown into the engine room, or being drawn into the 
 generator bearing, a guard "J" is fitted, which effectually 
 prevents the escape of this water, which is collected and taken 
 to a convenient point through the drain "K." 
 
 Care should be observed that the piping is arranged in 
 accordance with the foregoing, and that the rings are free and 
 have a side or axial clearance of about .001 5" or .002" in the 
 grooves, and that they are circular and fit inside of the gland 
 ring " G" snugly and uniformly all around, yet they should not 
 grip tightly enough on the inside of the sleeve "G" to prevent 
 
 14 
 
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 15 
 
SECTION A -A 
 
 FIG. 11 
 
 16 
 
them from being pushed axially. In operation, the rings 
 remain stationary. 
 
 In some of the larger non-condensing turbines, and 
 turbines designed for condensing operation, water glands 
 similar to those used on the larger units are employed. A 
 section of one of these is shown in Fig. 1 1 . The water supplied 
 to the gland inlet connection should be commensurate with 
 the back pressure to be employed viz., it should be 5 pounds 
 greater than the back pressure. All condensing turbines 
 should have their water glands furnished with water at 5 
 pounds pressure above atmosphere. 
 
 The water glands are provided with a water outlet con- 
 nection as shown, which should remain closed when the 
 turbine is operating condensing. When operating with back 
 pressure, the valve should permit a small amount of water to 
 escape from the glands, so as to provide a slight circulation 
 through the glands thus maintaining the temperature below 
 that of evaporation. Otherwise, the water would boil and the 
 steam formed would pass into the engine room. 
 
 The most common method of furnishing water of 
 requisite pressure is to connect the oil cooler with a source of 
 water supply, afterwards discharging this water into an ele- 
 vated overflow at the requisite height above the axis of the 
 turbine to give the proper pressure the pipe leading to the 
 overflow being provided with a connection to the glands. The 
 provision of an elevated tank, furnished with a ball float is an 
 alternative to be considered. 
 
 Bearings. All bearings used on these machines are 
 of the split babbitted type, oil being supplied from the oiling 
 system to be described later, though in some cases the bearings 
 are ring oiled, or have ring oiling in addition to forced lub- 
 rication. 
 
 The design of a bearing is shown in Fig. 12. The four 
 keys in the center, located above, below and at the sides, have 
 liners beneath them, the manipulation of which permits ready 
 adjustment of the rotor up and down and sideways, with 
 reference to the stationary elements. The inboard generator 
 bearing also serves for adjusting the axial clearances of the 
 rotor, and it is by means of this that the position of the tur- 
 bine rotor with respect to the nozzle blocks and reversing 
 chambers is determined. The thrust bearing journal and 
 means of adjustment is shown in detail in Fig. 13. The 
 thrust collars "B" and "C" are provided, having a hollow 
 pocket on one side in which split liners are inserted, shown at 
 
 17 
 

"D" and "E." The distance between "B" and "C" is kept 
 constant and the axial position of the shaft is determined by 
 shifting liners from one end to the other. Thus, when the 
 clearances have once been determined, if the turbine receives 
 proper attention, and if a proper quality of oil is employed, re- 
 adjustment should be unnecessary for an indefinite period. 
 To insure satisfactory running of the bearings, the radial 
 clearance allowed should be about .005" or .006", which is 
 also about the proper clearance axially. 
 
 It must be understood that in reality, the thrust bear- 
 ing does not have to take any end thrust, as the pressure on 
 either side of the revolving element of the turbine is the same. 
 The sole purpose of the thrust bearing is to definitely maintain 
 the axial position of the rotor. 
 
 In regard to bearings, it may be remarked for the bene- 
 fit of those not familiar with the operation of high speed 
 machinery that turbine bearings are operated at higher tem- 
 peratures than those of reciprocating engines, and should a 
 bearing feel disagreeably warm to the hand, it need cause no 
 anxiety to the operator. The bearings may be operated 
 satisfactorily for years, at a temperature of 150 or 160 degrees 
 F., without experiencing any trouble. 
 
 Governor and Oil Pump. As previously explained, 
 with the exception of the governors for the 10 and the 15 Kw. 
 turbines, all are of the vertical shaft type, driven from the 
 turbine shaft either by spur bevel gearing or worm and wheel. 
 Fig. 1 5 shows detail cross section through one of the vertical 
 shaft governors which is typical of those used on all turbines 
 except that it does not have the coupling between the 
 governor spindle and the oil pump spindle, as shown in Fig. 6. 
 
 The principle upon which this governor works is the 
 action of centrifugal force on weights which are counter- 
 balanced by means of the helical spring. The governor 
 weights, proper, are small steel cylinders, riveted between the 
 two governor weight arms made of sheet steel. At the lower 
 end of the governor weight arms, and riveted between them 
 are the governor arm blocks which carry the governor fulcrum 
 knife edge and governor weight knife edge blocks. The latter 
 are locked into the governor arm block and are held from lateral 
 movement by the governor weight arms. 
 
 Attached to the governor spindle is the governor weight 
 disc, upon which are mounted the governor weight disc ful- 
 crum blocks, which take the thrust of the governor weights. 
 Above the governor weight disc is mounted the governor 
 spring sleeve, which is loose on the governor spindle. This 
 
 19 
 
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 6 
 
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 1 I 
 
 6 
 
 20 
 
sleeve transmits the pressure from the governor knife edges 
 to the governor spring, and is connected by two governor 
 spring sleeve bolts to the governor sleeve, which is free to move 
 up and down, and revolve upon the governor spindle bushing. 
 
 The motion transmitted to the governor sleeve is im- 
 parted to the governor clutch carrying the trunnion to which 
 the governor clutch levers are attached, and through which 
 the motion of the governor weights is transmitted to the 
 governor valve, through the governor clutch lever link. 
 
 A governor sleeve nut is screwed on the lower portion 
 of the governor sleeve, to take the upward thrust of the gover- 
 nor sleeve upon the governor clutch. This nut is retained in 
 any position in which it is placed, by means of the pin and cot- 
 ter nut shown in the cross- sectional view. 
 
 The adjustment of the governor for determining the 
 speed and regulation of the turbine is obtained by means of 
 the governor adjusting spring nut and governor spring adjust- 
 ing seat. It will be noted in the section elevation and plan 
 view of the governor that a number of holes are provided in the 
 flange on the governor spindle adjusting nut, and also in the 
 governor spring adjusting nut seat, into which a pin may be 
 screwed and secured by the cotter pin. This permanently 
 fixes any adjustment which has been made, the governor 
 spring adjusting nut seat being held from turning on the 
 governor spindle by means of a pin and key way. 
 
 The lubrication of the various parts of the governor is 
 secured by supplying oil under pressure through the oil hole 
 which admits oil to the space between the governor spindle and 
 upper governor spindle bushings, through ports "A." From 
 the annular space between the governor spindle and spindle 
 bushing, the oil enters ports " B " which communicate with the 
 port "C" and supply oil to the governor sleeve, from which it 
 works its way through the ports "D" and "E," through the 
 trunnions of the governor clutch, and lubricates the governor 
 clutch trunnions. Part of the oil supplied to the ports "B" 
 goes to the thrust bearing under the governor weight disc 
 which carries the thrust due to the weight of the governor and 
 governor spindle. This thrust bearing consists of a number of 
 alternate brass and steel rings which are lubricated from the 
 port "B." 
 
 The oil collecting in the lower portion of the upper half 
 of the gear case passes through a port " F," and is led by a pipe 
 over the gears, or worm and gear, keeping the latter flooded 
 with a supply of oil. 
 
 21 
 
OCA/. SPRING ADO. NUT 
 
 COV. SPRING ADJ. NUT SCREW 
 
 CO/. SPRING ADO. NUT SCREW COTTER 
 
 GCV. SPRING ADO. NUT SEAT 
 
 GOV. GEAR CASE CAP 
 
 GOV. GEAR CASE 
 COVER 
 
 GOV. SPRING 
 
 GOV. SPRING 
 
 BOLT 
 
 OvJKMFEIEDCE BLOCK 
 
 RING UPPER 
 UST RING LOWEP 
 
 GOV.WORM OR 
 CCV.WORM GEAP 
 SHAFT 
 
 CCV. GEAR 
 LOWER HAL 
 
 LOWER GOV. 
 SPINDLE BUSHING 
 
 OIL PUMP GEAR DRIVEN 
 SHAFT BUSHING 
 
 FIG. 15 
 
 22 
 
A sight feed oiler is fitted to a branch of the oil pipe, 
 supplying the governor with oil, and gives a constant visible 
 indication to the operator, of whether or not the oil pump is 
 working properly. The discharge from this sight feed empties 
 into the upper portion of the governor case, and together with 
 the oil thrown from the governor, lubricates the governor gear 
 as before mentioned. It is important that the oil be contin- 
 ually overflowing at this point. 
 
 To obtain close regulation of speed, the scale or degree 
 of compression of the governor spring with a given increase in 
 compressor force upon it, must be properly adjusted or the 
 governor will be over- sensitive, or not sensitive enough. When 
 turbines are shipped from the shop, the governor has been ad- 
 justed for desirable speed variations, but should it become 
 necessary for any reason to adjust the regulation, this may be 
 done by tightening or loosening the governor spring adjusting 
 nut. If, upon trying adjustments in various positions, by 
 means of the governor spring adjusting nut, it is found that the 
 governor is unstable and hunts, the number of active coils of 
 the spring should be reduced by screwing the spring farther 
 onto the governor spring adjusting seat, thus increasing the 
 scale of the spring. However, if the governor is not sufficient- 
 ly sensitive, it is an indication that more coils of the spring are 
 required, and the spring should be unscrewed from the governor 
 spring adjusting seat. When the proper number of active coils 
 have been obtained, accurate adjustment of the speed and 
 regulation can be obtained by changing the position of the 
 governor spindle adjusting nut. To have close regulation, 
 there should be as little lost motion as is consistent with per- 
 fect freedom between the valve stem and the governor clutch 
 sleeve. 
 
 In adjusting the governor valve, the operator should 
 make sure that the governor valve seats tightly before the 
 governor reaches its extreme outer position. Otherwise, the 
 turbine is likely to go above normal speed and trip the auto- 
 matic throttle. If it is found that the turbine runs above 
 normal speed and trips the automatic throttle valve, when 
 operating without load on the generator, the governor valve 
 stem should be lengthened by loosening the governor valve 
 stem lock nut and unscrewing the valve stem from the upper 
 governor valve stem end, thus lengthening the valve*|stem and 
 bringing the valve down to its seat. Too much lengthening of 
 the valve stem will preclude a full valve opening, preventing the 
 turbine from carrying its proper loads. Assurance should be 
 had that the valve is steam tight, and is properly ground in. 
 
 23 
 
The oil pump is located below the oil reservoir, 
 and consists of two spur gears, one of which is keyed to the 
 lower governor spindle, and the other mounted on an idle 
 shaft running in bronze bushings. The principle of operation 
 is based on the fact that where the gears mesh together, the oil 
 is forced out from between the teeth, whereas around the peri- 
 phery, the openings are flooded with oil, which is carried 
 around from the inlet to the discharge side. No valves are 
 required in this type of pump, and as it is entirely flooded with 
 oil, no attention should be needed. The clearance between the 
 outer diameter of the teeth and the gear casing should be 
 about .005" as should also be the clearance .between the root 
 of one gear, and the top of the teeth of the other. The ver- 
 tical clearance between the gears and the casing should be 
 about .005", which is the thickness of the gasket put between 
 the oil pump case and the bottom of the oil reservoir. In this 
 connection, it must be noted that care must be taken in cut- 
 ting out this gasket, and also that the portion cut out for the 
 gears and the oil intake and discharge are clean cut, to prevent 
 pieces of gasket from getting into the gears. 
 
 An oil gauge is fitted on each oil reservoir to show the 
 amount of oil in the system, and the oil should be carried 
 within about an inch, or inch and a half of the top of the gauge, 
 when the turbine is standing idle. 
 
 Automatic Stop Governor. A detail cross section 
 through the automatic stop governor is shown in Fig. 14, and 
 in Fig. 1 6 its connection to the throttle valve. The stop 
 proper is contained within the governor drive extension shaft, 
 and consists of a plunger "A" and spring "B." Adjusting 
 liners are inserted or removed from "C" for changing the 
 speed at which it trips. 
 
 As indicated in the diagrammatic sketch, the center of 
 gravity of the plunger is generally located about %" from the 
 center of rotation, and the scale or strength of the spring is so 
 selected that when the plunger begins to move outwards the 
 centrifugal force, acting on the plunger, increases more rapidly 
 than the pressure of the spring. The travel of the plunger, 
 when it is tripped, is limited by the shoulder " D." 
 
 The automatic stop should operate at about 10% or 
 12% above normal speed, and when it has once been adjusted, 
 should not require adjustment, unless it has been apart for 
 cleaning or inspection. When the automatic stop has been 
 taken apart, either for adjustment or cleaning, care should be 
 taken to put back the cotter pin, which prevents the nut from 
 unscrewing. 
 
 24 
 
Periodically, the automatic stop should be tested to 
 see that it is operating properly, which may be done by pulling 
 up on the governor valve stem, thus permitting the turbine to 
 over speed, and noting the speed at which the automatic stop 
 trips. This should be done several times and the operator 
 should insure himself that the stop trips within 2 or 3% of the 
 same speed several times in succession, to make sure that the 
 stop is not tripped from the slight vibration of the shaft. Also, 
 to insure that the stop is not sticking. 
 
 When the automatic stop plunger flies out, it strikes the 
 automatic stop trigger shown in the cross section, Fig. 16, 
 which is attached to the throttle valve latch rod, throwing it 
 in the direction of the arrow and releasing the throttle valve 
 latch, which permits the spring in the automatic throttle valve 
 to close the valve. 
 
 Automatic Throttle Valve and Governor Valve. 
 
 A detailed assembly of the automatic stop and governor valve 
 is shown in Fig. 16, from which the construction is easily seen. 
 The steam enters in the space around the steam strainer, 
 which surrounds the automatic stop valve, and prevents any 
 scale or other extraneous material from entering the turbine. 
 
 The stop valve is of the balanced type, and operates as 
 follows:- When closed, the throttle valve by-pass valve is on 
 its seat, thus preventing the escape of steam from the space 
 "C" into the space below the valve, which is at atmospheric 
 pressure. Steam, therefore, which leaks between the throttle 
 valve piston and cylinder, on the lower part of the throttle 
 valve yoke, enters the space "C" and holds the valve firmly 
 upon its seat. When the throttle valve hand wheel is turned 
 to open the valve, the throttle valve bypass valve is raised 
 from its seat, permitting the steam in the space " C " above the 
 throttle valve piston to assume the same pressure as below the 
 valve disc. This renders the valve practically balanced, per- 
 mitting it to be readily moved by further motion of the hand 
 wheel until the throttle valve stem collar comes against the 
 throttle valve stem nut. The throttle valve stem nut is loose, 
 and free to move up and down within the extension of the 
 throttle valve yoke. In the position shown in Fig. 16, the 
 throttle valve is closed and the throttle valve stem nut is in 
 its upper position, being held there by the throttle valve latch 
 which has been mentioned, and remains in the position in- 
 dicated until released by the tripping of the automatic stop. 
 The throttle valve stem nut is kept from turning by the throttle 
 valve latch, which acts as a dowel. When the throttle valve 
 
 25 
 
(to: 
 
 U UJ . 
 
 UJ > > U D 
 
 I- I- O O t- O < 
 
 CO CO O O CO o O 
 
 o o o o o 
 cr cc a: o: cc 
 
 r r r r r 
 
 CO 
 I I 
 
 6 
 
 
 >' >* >' >' >' >' >' >' >' >" >' 
 
 ooooooooooo 
 ooooooooooo 
 
 26 
 
latch is released by the tripping of the automatic stop, the 
 pressure of the throttle valve spring on the throttle valve stem 
 nut forces the latter downward, closing the valve, providing 
 the latter has been opened. 
 
 From the construction, it will be evident that the 
 throttle cannot be opened after it has been tripped by the 
 automatic stop, until the throttle valve hand wheel has been 
 turned around in the direction required to close the valve, and 
 until the throttle valve stem nut is brought to its upper posi- 
 tion, and has caused the throttle valve latch guide rod to en- 
 gage with the throttle valve latch, and hold it in the position 
 shown in Fig. 16. Furthermore, it will be evident that the 
 automatic releasing of the throttle valve is possible in any 
 position, whether wide open, or only partially open. 
 
 The steam after passing through the automatic throttle 
 valve, enters the space above and below the governor valve. 
 The latter is of the double disc poppet construction, thus being 
 entirely balanced for steam pressure. The only force required 
 to move it, is that necessary to overcome a slight friction of 
 the valve stem in the valve stem bushing and valve cage 
 guides. As will be noted, from the cross section, the valve 
 cage is not bolted into the steam chest body but is held on its 
 seat by means of a spring which permits it to expand and con- 
 tract without warping the valve seats. The lower end of the 
 valve cage is free to expand and contract without resistance, 
 steam tightness being obtained by the valve body being ground 
 into the steam chest, and the governor valve cage spring seat 
 and governor valve cage spring seat ring, shown in the draw- 
 ing. The valve is so constructed that it has to be moved about 
 1/32 " before steam begins to pass, thus preventing cutting of 
 the valve and valve seats when steam is being throttled 
 through the valve at light load. 
 
 Steam tightness, where the valve passes through the 
 valve bonnet is obtained by a plain bronze bushing and a 
 small soft packing washer, which need not be made very tight, 
 however, as any steam leaking past the bushing will escape 
 through the drain port "O." A more elaborate metallic 
 packing of well known type is employed in the larger sizes. 
 
 27 
 
The Westinghouse Machine Company 
 
 Designers and Builders of 
 
 Steam Turbines Stokers 
 
 Steam Engines Gas Producers 
 
 Gas Engines Pumps 
 
 Condensers Blowers 
 
 Turbo Compressors 
 
 SALES OFFICES 
 
 New York 165 Broadway 
 
 Chicago 39 South La Salte Street 
 
 Pittsburgh Westinghouse Building 
 
 Philadelphia 1003 North American Building 
 
 Boston 201 Devonshire Street 
 
 Atlanta Candler Building 
 
 Denver Gas & Electric Building 
 
 Detroit 27 Woodward Avenue 
 
 Cleveland 1117 Swetland Building 
 
 Cincinnati 1 102 Traction Building 
 
 San Francisco Hunt Mirk & Co., 141 Second St. 
 
 City of Mexico Cia Ingeniera, Importadora y Contratista, S. A. 
 
 Havana, Cuba Galban & Company 
 
 San Juan. Porto Rico Porto Rico Construction Co. 
 
 Iquique, Chile J. K. Robinson & Co. 
 
 Tokio, Japan Takata & Company 
 
 Caracas. Venezuela. . . H. I. Skilton 
 
 GENERAL OFFICES AND WORKS 
 
 EAST PITTSBURGH, PA. 
 
THIS BOOK IS DUE ON THE LAST DATE 
 STAMPED BELOW 
 
 AN INITIAL FINE OF 25 CENTS 
 
 WILL BE ASSESSED FOR FAILURE TO RETURN 
 THIS BOOK ON THE DATE DUE. THE PENALTY 
 WILL .NCREASE TO 5O CENTS ON THE FOURTH 
 DAY AND TO $1.OO ON THE SEVENTH DAY 
 OVERDUE. 
 
 
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