| 摘要 |
A fusion welding socket for coupling together double walled plastic conduits including an inner pipe, an outer pipe surrounding the inner pipe and an annular space arranged between the inner and outer pipes. The fusion welding socket includes a main body comprising a first end portion, a second end portion and an intermediate portion. The intermediate portion has at least one inner diameter which is smaller than the inner diameters of the first and second end portions. Three heating coils are embedded in the first end portion, the second end portion and the intermediate portion, respectively, for fusing together the first and second end portions with a respective outer pipe of a first and second conduit and the intermediate portion with a respective inner pipe of the first and second conduit. A passageway includes an annular space is arranged to connect the annular spaces of the first and second conduit after fusion. |
