Abstract: An automatic grease injection system comprises a host module, a shunting module and a control module; the host module comprises a power device and a grease injection device, in which the power device drives the grease injection device to output sealing grease; the shunting module comprises a control valve and a connecting pipeline, the connecting pipeline comprises a plurality of shunting branch pipes and a grease injection main pipe which are connected to each other, in which the grease injection main pipe is connected to the grease injection device, and each of the shunting branch pipes is connected to a device to be injected with grease, and sealing grease output by the host module is selectively connected to the device to be injected with grease through the shunting module; the control module is to output control signals to the host module and the shunting module.

Abstract: A fracturing transportation system, which includes a high-low pressure manifold skid, including a plurality of first high-pressure input ends and a first high-pressure output end; a plurality of first high-pressure pipes, arranged in one-to-one correspondence with the first high-pressure input ends, an end of one first high-pressure pipe is directly connected with a corresponding one of the first high-pressure input ends, and another end of the first high-pressure pipe is configured to be directly connected with an output end of a fracturing device; and a second high-pressure pipe, an end of the second high-pressure pipe is directly connected with the first high-pressure output end; the first high-pressure pipe and the second high-pressure pipe are configured to bear a pressure greater than or equal to 100 MPa, and at least one of the first high-pressure pipe and the second high-pressure pipe adopts a high-pressure flexible pipe.

Abstract: A flexible pipe end portion connection structure is provided. The flexible pipe end portion connection structure includes a flexible pipe body and a joint. The joint includes a first end and a second end opposite to each other and has a channel extending through the joint in a direction from the first end to the second end. An inner sidewall of the first end of the joint has a plurality of first stepped structures, and an inner diameter of a portion of the channel corresponding to the first stepped structure gradually decreases in the direction from the first end to the second end. At least a part of an end of the flexible pipe body is inserted into the first end of the joint to fit with the first stepped structure.