This invention provides a device capable of covering the surface of an object situated in a gas with a region filled with a liquid and of moving such region, capable of sucking and collecting such liquid from the surface of the object wetted by the liquid and of drying such surface, and is capable of allowing such region to adhere to and crawl along the surface of the subject, while conducting ultrasonic flaw detection or ultrasonic cleaning of the surface of the object.This invention provides a device comprising a stereoshaped first region having an annular surface A and a stereoshaped second region having an annular surface B wherein the surface A is the boundary surface between the surface of an object and the first region and the surface B is the boundary surface between the surface of an object and the second region, the portion defining the outer boundary of the surface A is provided with an outer seal member, the portion defining the inner boundary of the surface A is provided with an inner seal member, the first region is connected to a gas suction means, the second region is connected to a liquid supply means, the first region is located on the downstream side of the gas surrounding the device, the first region is located on the downstream side of the second region, and the liquid flowing out of the second region reaches the first region and is subsequently transported by suction to the suction means.