Submersible pump with barrier fluid isolation of motor lubricating liquid from pumped product

• Main Authors: Cain, Sean A, Brown, John L
• Format: Patent
• Language: English
• Published: 15.11.2022
• Subjects: BLASTING; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; DYNAMO-ELECTRIC MACHINES; EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; ELECTRICITY; FIXED CONSTRUCTIONS; GENERATION; HEATING; LIGHTING; MECHANICAL ENGINEERING; MINING; NON-POSITIVE DISPLACEMENT PUMPS; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; WEAPONS

An electrical submersible pump (ESP) isolates its motor lubricant from pumped product without requiring a bellows, diaphragm, bladder, or external lubricant pressurizing system. A pair of nested isolation chambers below the motor housing are filled with a barrier fluid that is non-reactive, non-miscible, and higher in density than the pumped product and the motor lubricant. As the motor lubricant expands and contracts after pump start-up and shut-down, motor lubricant and barrier fluid are exchanged between the motor housing and the isolation chambers via three interconnections, while pumped product is exchanged with the inner barrier chamber, while being isolated from the motor housing. The interconnections extend between the bottom of the motor housing and the bottom of the outer barrier chamber, between the top of the outer barrier chamber and the bottom of the inner barrier chamber, and between the top of the inner barrier chamber and the pumped product.