The overall structure of the built-in electric pump is vertical and downward type with built-in motor structure.The motor housing has an interlayer. When water drains, the water flows from the interlayer and goes out from the top to cool the motor. Even without water, the interlayer outside the motor still has water cooling the motor to ensure that the motor will not be overheated and burnt. There is no need for supervision, greatly reducing the cost of labor. Most of our single-stage and multi-stage pumps utilize the built-in structure