The utility model refers to a tubular elastic sensing element connected by a foldable wrinkled sheet along the folding direction. Bellows are widely used in instruments, mainly used as measuring elements of pressure measuring instruments to convert pressure into displacement or force. The corrugated pipe has a thin wall, high sensitivity, and a measurement range of tens of Pa to tens of MPa. Its open end is fixed, the sealing end is in a free state, and the auxiliary coil spring or reed is used to increase the elasticity. When working, it will stretch along the length of the pipe under the action of internal pressure, so that the movable end will produce displacement that is related to the pressure. The movable end drives the pointer to directly indicate the pressure. Bellows are often combined with displacement sensors to form pressure sensors that output electricity, and sometimes they are also used as isolation elements. Since the expansion of bellows requires a large volume change, its response speed is lower than that of Bourdon tube. Bellows are suitable for measuring low pressure. Bellows mainly include metal bellows, corrugated expansion joints, corrugated heat exchange tubes, diaphragm bellows and metal hoses. Metal bellows are mainly used to compensate thermal deformation of pipelines, shock absorption, absorption of pipeline settlement deformation and other functions, and are widely used in petrochemical, instrument, aerospace, chemical, power, cement, metallurgy and other industries. Corrugated pipes made of plastic and other materials play an irreplaceable role in media transmission, power threading, machine tools, household appliances and other fields.