Combined-type pipe fitting for connection of thermal insulation pipes

The utility model provides a combined-type pipe fitting for connection of thermal insulation pipes, and belongs to pipe fittings for the connection of pipelines for conveying fluid. The combined-type pipe fitting comprises a tee joint, a through joint, an elbow and a gap bridge, wherein the tee joint is formed through combination of an inner pipe fitting and an outer sheath matched with the inner pipe fitting. The combined-type pipe fitting is characterized in that the inner pipe fitting is a medium density polyethylene pipe (namely a PE-RT pipe) or a polybutylene pipe (namely a PB pipe) or a polypropylene random copolymer pipe (namely a PP-R pipe); the outer sheath is a polyvinyl chloride sheath or a polypropylene sheath or a polyethylene sheath (namely a PE sheath); and a thermal insulation layer formed by a polyurethane foaming layer is arranged between the inner pipe fitting and the outer sheath. Through a try-out, a connection part of a thermal insulation pipe in a pipeline project can have the same heat