The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

January, 1917 and bottom, and operate with a mini- mum of noise. The vertical-drive shaft is hung on a ball thrust bearing contained in the gear case. They are fitted with 6-inch suctions and 6-inch discharges, so arranged that each pump can take suction from either or both compartments, port and star- board, at the same time, or independ- ently. Cargo may also be discharged with one pump or as many pumps as can be put into operation at one time, depending entirely on the capacity of discharge pipes to the shore tanks. Any number of commodities can be discharged at the same time without mixing, depending, of course, on the number of discharge lines that are available to the shore tanks.. The dis- charge lines from the pumps are so elasticity in the event of one or more pumps going out of commission. All operating valves are located on the upper deck. The motor control for starting the pumps is located in the main engine room and will be de- scribed in more detail hereafter. When it is desired to start any particular pump, the deck officer gives the signal to the operator in the engine room. The pumps are thus under direct con- trol at all times by the engineer on watch. Since LA BreA went into commis- sion she has handled over 500,000 bar- rels of oil, and in each case the dis- charge was completed with a material saving in time as compared with ves- sels with ordinary pumping system. The capacity of the pumping system THE MARINE REVIEW 9 each individual tank, the most logical way of driving the pumps was_ by independent electric motors. In de- termining the proper type of motor, several propositions were considered. Inasmuch as the drive of the pump was vertical, both vertical and _ hori- zontal motors were considered. Twen- ty-five cycle would have permitted us- ing a slow-speed vertical motor suit- able for direct connection to pump without any gearing, but this necessi- tated the installation of special 25- cycle turbine generating sets. The higher speed of 60-cycle motors re- quired connection to pump through vertical gears if vertical motors were used, and this was not considered practical, The horizontal motors, whether 60 or 25 cycle, required the FIG. 5—DECK VIEW OF LA BREA SHOWING PUMP MOTOR INSTALLATION arranged that they can be also used as filling lines to each individual tank, by means of a bypass around the pump. Both Mr. Kibele and the writer, from the start, believed that half the number of pumps would meet all re- quirements, but finally decided to take no chances on the first installa- tion. The better and more economical plan would be to connect the smaller number of pumps to a common 6-inch suction line, fitted with gate valves at each bulkhead and independent suction to each tank. This would enable each pump to draw from all or any of the tanks and insure maximum is, of course, regulated by the ca- pacity of the discharge lines and the pressure that the pumps are subjected to. On a _ low-discharge head, and with ample shore connections, the en- tire cargo could be discharged in ap- proximately 10 hours’ time. The maxi- mum quantity of oil handled per hour against a pressure of 110 pounds per square inch is reported to be 4,200 barrels. The economy in fuel saved with this pumping installation ap- pears to be approximately 45 per cent over the ordinary manner of dis- charging a liquid cargo. After it was determined to use this system of pumping, with a pump in use of bevel gears. All the power companies operating on the Pacific coast and the various refining and loading stations of the Union Oil Co. use 60-cycle current, and the installa- tion of 60-cycle motors had the ad- vantage of being able to use shore power to drive the cargo pumps if required. Ordinarily the pumps and motors would be required to start up against line pressure, and this would necessi- tate a high-starting torque slip-ring motor with its necessary starting re- sistance and controler. With this type of motor there is sparking at the collector rings and the controler fin-