Abstract: Available water depth for the conventional insulated pipe is generally less than 300 m, and it is not suitable for application in offshore oil exploration. A new deepwater riser insulation molding process is developed. The insulation structure of the insulation mold is consisted of GSPU tube, a non-elastic elastomer, and its insulating capacity is from the hollow glass beads filled inside it. Generally, the insulation mold is divided into inner cavity(forming space of insulation layer), outer cavity, insulation layer, outer shield, pouring hole and vent, etc., and the space between the inner and outer cavity is a channel for heated oil flowing. Taking the 273-mm pipe as an example, the mold design in temperature control system including the auxiliary equipment consisted of foundation, lifting system and pipe end sealing, etc. is discussed.