Novel pipe section expansion joint

The invention discloses a novel pipe section expansion joint which is mainly composed of a front straight pipe section, a fixing support, two steam cylinders, a pushing plate, connecting members, a pneumatic system and a rear straight pipe section. The pushing plate is fixedly arranged on the periphery of the front portion of the front straight pipe section, a flange is arranged at a front port of the front straight pipe section, the steam cylinders are fixedly arranged on the fixing support, shaft heads of the steam cylinders are fixedly connected with the pushing plate through the connecting members, the rear straight pipe section corresponding to the front straight pipe section is arranged on the fixing support, a detected flowmeter is arranged between the front straight pipe section and the rear straight pipe section, the pneumatic system is arranged on the lower portion of the fixing support, and a pressure transmitter is arranged on the front straight pipe section. The novel pipe section expansion joint overcomes the defects of conventional expansion joints, is exquisite and reasonable in structure and lower in manufacturing cost, meets needs on measuring pressure and temperature at different positions of various flowmeters during experiments and is more suitable for meeting meter-clamping requirements of large-caliber expansion joints.