Patent ID: 8003181

Claim:
An anticorrosion sleeve comprising: a resin sleeve having a large-diameter portion and a small-diameter portion on the inner circumference thereof and a transition therebetween that defines, when viewed in cross-section, a step, the resin sleeve further comprising a circular groove recessed into the inner circumference of the small-diameter portion such that the groove is defined by opposing side walls spaced apart from one another, wherein the circular groove is positioned on an upper end of the small-diameter portion proximate the step; and a metal sleeve to be tightly received in the resin sleeve so that the metal sleeve expands the resin sleeve in diameter when the metal sleeve is inserted into the resin sleeve, the metal sleeve comprising an engagement end portion, an intermediate portion, and a tapered end portion having an outer diameter that gradually decreases toward the intermediate portion; wherein the intermediate portion of the metal sleeve is passed through the large-diameter portion of the resin sleeve to be ready to expand the small-diameter portion of the resin sleeve in diameter before further pushing the metal sleeve into the resin sleeve, and wherein the tapered end portion of the metal sleeve is ready to be tightly engaged with the large-diameter portion in a manner such that the metal sleeve expands the large-diameter portion in diameter; and wherein the metal sleeve comprises a projected ring portion on a lower end of the outer circumference of the engagement end portion; wherein the metal sleeve is connected to the resin sleeve with the projected ring portion engaged with the circular groove as a partially assembled position with the tapered end portion exposed from the resin sleeve; wherein the metal sleeve and resin sleeve, connected in the partially assembled position, are insertable into an opening in a pipe.