CORROSION PREVENTIVE COVERING METHOD OF EXPOSED STEEL SURFACE OF STEEL PIPE COVERED WITH POLYOLEFIN CORROSION PREVENTIVE COVERING

摘要

PURPOSE:To cover an exposed steel surface of a steel pipe covered with a polyolefin corrosion preventive covering with a preventive covering, by applying a special primer to a part where a sealant will be applied, applying the sealant, and heating a heat- shrinkable covering material so that the heat-shrinkable covering material is shrunk and at the same time pressed and bonded to the sealant layer. CONSTITUTION:A primer 4a containing a reaction setting resin capable of adhering to polyolefins is applied to a surface 4 of a corrosion preventive covering layer where a sealant will be applied. A sealant 5 consisting mainly of the reaction-setting resin capable of adhering to a steel pipe is applied at least to a steel pipe exposed surface 3 and the primer 4a at the edges of the corrosion preventive covering layer. A heat- shrinkable covering material 6 with a primer 7 containing a reaction-setting resin capable of adhering to polyolefins applied on one surface of the material 6 is placed on the sealant layer with the primer 7 opposed to the sealant layer 5, and before the completion of the hardening reaction of the applied primer, the covering material 6 is pressed and bonded to the sealant layer 5 while the heat-shrinkable covering material 6 is heated to be shrunk.