Field coating for welded joint technique of 3PE pipeline

Application procedures and requirements of field coating for welded joint by heat shrinkable sleeves and liquid epoxy are introduced. Advantages and disadvantages of the two techniques are analyzed and compared. Specific countermeasures to eliminate the bonding between liquid epoxy and 3PE coating, namely changing the set width of parent coating of pipe joint prefabricated in coating yard, are introduced so as to improve the bonding capacity of liquid epoxy with 3PE coating. Field coating for welded joint by liquid epoxy to instead heat shrinkable sleeves is recommanded in order to improve the quality of field coating for welded joint for 3PE pipe.