The invention discloses a preparation method of a heat-fusible modified
polyvinyl chloride (PVC)
pipe. The preparation method is characterized in that the
pipe is prepared by mixing 100 parts by weight of PVC resin, 1.5-6.0 parts by weight of a
plasticizer, 0.5-4.0 parts by weight of an activator, 3.0-8.0 parts by weight of a
toughening agent, 4-10 parts by weight of an
impact modifier, 1 part by weight of
barium stearate, 0.5 part by weight of an
ultraviolet absorber, 2-6 parts by weight of a stabilizer and 1.0-5.0 parts by weight of
epoxy resin, stirring, mixing and then extruding for molding. Compared with the prior art, by adopting the preparation method disclosed by the invention, heat-fusible
welding is realized, the use of a
flare and an
adhesive in butting construction of PVC pipes is eliminated, and the production and construction cost is reduced by about 20-30%; and furthermore, the
pipe has good
impact resistance, high tensile strength, long service life, high
welding strength and firm connection, and is particularly suitable for butting of the PVC pipes in trenchless
engineering construction.