UNION OIL COMPANY OF CALIFORNIA’S TANK STEAMER LA BREA. 199 
Work had been progressing very rapidly on the hull construction, but the mo- 
tors and generating apparatus could not be ordered until after the amount of power 
required to operate the pump had been determined. An experimental pumping plant 
was installed, and it was some time before the data were available, with the result 
that shipment became very important and was the deciding factor why certain types 
of motors, etc., were selected. The cargo motors are installed, as previously stated, on 
the main deck, exposed to weather conditions and salt water, and so it was decided 
to use the open type and to enclose the same in a water-tight casing supplied by the 
builder. 
Ordinarily the pumps and motors would be required to start up against line pres- 
sure, and this would necessitate a high-starting torque slip-ring motor with its nec- 
essary starting resistance and controller. With this type of motor there is sparking 
at the collector rings and the controller fingers, and, as the motors would be in- 
stalled on deck where explosive gases might be present, it was not considered prac- 
ticable to use the same; consequently it was decided to use the ordinary squirrel- 
cage type. This motor, however, does not have torque sufficient to start a pump 
against full line pressure, and it was necessary to install a bypass on the cargo 
pumps. Pumps are brought up to full speed with the bypass open, which is gradu- 
ally closed, at the same time opening up the valve in the discharge line. 
As already stated, there are twenty-two of these cargo pumps, and each is 
equipped with a motor of the following rating:—4o0 horse-power, 600 revolutions 
per minute, 3 phase, 60 cycle, 220 volt, horizontal, squirrel cage of the open type 
construction (Fig. 12, Plate 120). 
The motors are enclosed in a water-tight casing, as stated above, and this was 
made of cast iron. When loaded it is necessary for the motors to have proper ven- 
tilation, and the enclosing case is equipped with several hand-hole covers, which are 
opened when the motor is in service (Fig. 10, Plate 118). The motors ordered for 
the next installation are exactly the same, except they are enclosed and no additional 
water-tight casing will be required. 
In addition to the cargo pump motors the following motors were installed in the 
engine-room, depending on the same power plant :— 
One 60 horse-power, 720 revolutions per minute, 3-phase, 60-cycle, 220-volt, 
horizontal open-type motor, direct connected to circulating pump for main con- 
denser. 
One 50 horse-power, 3,600 revolutions per minute, 3-phase, 60-cycle, 220-volt 
motor, direct connected to one boiler feed centrifugal pump. 
One 35-horse-power, 1,800 revolutions per minute, 3-phase, 60-cycle, 220-volt 
motor, direct connected to centrifugal ballast pump. 
The power plant is located on a gallery over the thrust shaft at the after end 
of the engine-room and consists of two turbo-generating sets :— 
One 375 K-va, and one 125 K-va, 3,600 revolutions per minute, 3-phase, 60- 
cycle, 240-volt generators, direct connected to General Electric Curtis condensing 
turbines, with direct-connected exciter (Fig. 13, Plate 121). 
