Double suction pump

A pump apparatus, comprising:

• a frame;
• a drive shaft;
• an impeller mounted on the drive shaft;
• a first hydraulic motor connected to the frame and to a first end of the drive shaft;
• and
• a bearing structure connected the frame and to a second end of the drive shaft, wherein the bearing structure comprises a second hydraulic motor,
• a first fluidic connection that supplies hydraulic fluid to the first hydraulic motor;
• a second fluidic connection that removes hydraulic fluid from the first hydraulic motor and then supplies the hydraulic fluid removed from the first hydraulic motor to the second hydraulic motor;
• and
• a third fluidic connection that removes hydraulic fluid from the second hydraulic motor;
• and
• wherein the first end of the drive shaft includes a bored and keyed opening that is configured to receive an output shaft of the first motor and to form a mechanical coupling with the output shaft of the first motor.

A method of operating a pump apparatus that includes a frame, a drive shaft, an impeller mounted on the drive shaft, a first hydraulic motor connected to the frame and to a first end of the drive shaft and a bearing structure connected the frame and to a second end of the drive shaft wherein the bearing structure includes a second hydraulic motor, the method comprising:

• conveying pressurized hydraulic fluid from a hydraulic fluid supply system to the first hydraulic motor to cause the first hydraulic motor to impart rotational motion to the drive shaft;
• conveying hydraulic fluid exiting the first hydraulic motor to the second hydraulic motor to help cool and lubricate the bearing structure;
• and
• conveying hydraulic fluid exiting the bearing structure back to the hydraulic fluid supply system.