The invention discloses a flow guiding device which comprises a clamping mechanism. The clamping mechanism comprises an upper fixing plate, a lower fixing plate, an adjusting screw, guide rods, an upper pressing plate, a lower pressing plate, an upper adjusting plate and a lower adjusting plate. The upper fixing plate, the upper adjusting plate, the upper pressing plate, the lower pressing plate, the lower adjusting plate and the lower fixing plate are sequentially arranged from top to bottom. The adjusting screw and the guide rods are arranged between the upper fixing plate and the lower fixing plate. The upper pressing plate and the lower pressing plate are symmetrically arranged in the vertical direction. Each of the upper pressing plate and the lower pressing plate is provided with a guiding hole and a wire clamping hole, wherein the guiding hole corresponds to the corresponding guide rod. The upper pressing plate and the lower pressing plate are installed on the guide rods through the guiding holes. The parts, between the upper pressing plate and the upper adjusting plate, of the guide rods are each provided with a spring. The upper fixing plate, the lower fixing plate, the adjusting screw, the guide rods, the upper adjusting plate and the lower adjusting plate are made of insulating materials. The flow guiding device can complete the cleaning work on the outer surface of the position of a heating joint in an electrified state, and the treatment efficiency is effectively improved.