252 STANDARD LUBRICATING OIL SYSTEM FOR GEARED TURBINES. 



and gears, and also at oil cooler outlets. The gauges showing the pressure of oil 

 from the cooler and the water pressure into the cooler should be placed at the 

 same level, and the oil pressure gauge should always read higher than the water 

 gauge. If there is a leak, it is preferable that it shall be from the oil to the water. 



9. Filling line to gravity and reserve tanks shall lead from a convenient loca- 

 tion on deck, through a swinging pipe under the deck, to highest point of discharge 

 line to funnel and valve, as shown in drawing E-i 1000-10 (Plate 108.) All tanks shall 

 be properly vented with large goose-neck vent pipes extending at least 3 feet high. 

 The vent pipe on gravity tanks shall be the same size as overflow pipe, and may be 

 connected by tee fitting to overflow pipe where it connects to gravity tanks. Oil 

 drain piping from bottom of gravity tanks shall be led directly with uniform drop 

 through filter to drain tank. 



10. All pipe sizes shall be determined on the basis of 175 gallons of oil per 

 minute (the oil having a viscosity of 500 seconds Saybolt at 100° F.) at the follow- 

 ing velocities: — ^Oil in drain return pipes from bearings and gears not to exceed 

 80 feet per minute; oil in suction lines not to exceed 125 feet per minute; oil in 

 discharge and supply lines not to exceed 250 feet per minute. Due allowance shall 

 be made for friction in bends and fittings, in order that pressure of oil at supply 

 manifolds shall be at least 10 pounds per square inch. 



11. There shall be a glass sight flow indicator installed in the overflow line 

 fitted with electric light, and so located as to be visible from operating stations. 

 There shall also be connected to the gravity tanks three ^-inch lines at high, in- 

 termediate and low levels of oil in the gravity tanks respectively and these pipes 

 will be led through sight flows on engine-room gauge board to the drain tank. The 

 glass of indicator shall be marked as follows: — "High Level" — "Intermediate 

 Level" — "Low Level." When oil stops flowing at "Low Level," shut down tur- 

 bines and investigate, an electric light to be placed behind indicator. 



Approved type of oil flow indicator or telltales with vapor or air relief shall 

 be mounted on each bearing. 



12. Where cocks are installed in supply lines to bearings or oil sprays, for initial 

 adjustment of flow, they shall be of a type requiring a special handle or key (kept 

 in chief engineer's room). They shall also be arranged to permit a small amount 

 of oil to flow even if left in "shut" position. Only cocks will be allowed for this 

 control, as there is a danger of valves closing in the event of heavy vibrations. 



B. Thermometers. — Thermometers shall be 9 inches, separate socket. Class A 

 as per Navy Department S. E. Print B-56, graduated from 30° F. to 220° F., located 

 as indicated on Plan E- 1 1000-10 (Plate 108), i. e., one at turbine thrust discharge 

 and one at forward turbine bearing oil outlet; one at after turbine bearing oil out- 

 let ; one at combined oil drain from gear casing ; one at main thrust bearing oil out- 

 let ; one at oil inlet to coolers ; one at oil outlet from coolers ; one at cooling water 

 inlet, and one at cooling water outlet. A thermometer shall also be placed on each 

 gravity tank. If cross-compound turbines are used, the thermometers above speci- 



