Splicing mechanism and corrosive gas exhaust system for laboratory

The utility model relates to the technical field of gas treatment, in particular to a splicing mechanism and a corrosive gas exhaust system for a laboratory, which comprises a pipeline unit and a fixing unit, the pipeline unit comprises a plug assembly, an upper pipeline assembly arranged below the plug assembly and a lower pipeline assembly arranged below the upper pipeline assembly; the fixing unit comprises a fixing assembly, an upper sealing assembly connected between the plug assembly and the upper pipeline assembly, a lower sealing assembly connected between the upper pipeline assembly and the lower pipeline assembly, and a switching assembly arranged in the upper pipeline assembly. The utility model has the beneficial effects that the lower gas pipe not only can freely adjust the inlet angle of waste gas, but also can be fixed at a specified angle at any time, so that the instability of equipment caused by continuous rotation of the lower gas pipe is avoided; finally, the problem that the position of t