PRESTRESSING STEEL STRAND AND PRESTRESSING STEEL BAR, HAVING RUST PREVENTING COATING AND EXCELLENT IN ADHESION AND PRODUCTION THEREOF

摘要

PURPOSE: To obtain a prestressing steel material, having a rust preventing coating, used in prestressed concrete(PC) and improved in adhesion to the concrete and a method for producing the prestressing steel material having the rust preventing coating. ;CONSTITUTION: This prestressing steel material having a rust preventing coating is obtained by forming a rust preventing coating layer 11 composed of a thermoplastic resin on the whole periphery of each prestressing steel material 3 composed of a prestressing steel strand or steel bar having a rust preventing coating and integrally forming a regular helical protruding ridge 15 composed of the thermoplastic resin on the surface thereof. This method for producing the prestressing steel material having the rust preventing coating is to form a regular helical ridge pattern composed of the thermoplastic resin on the surface of the prestressing steel material by using a step for melting the thermoplastic resin in an extruder and coating the prestressing steel material composed of the prestressing steel strand or steel bar with the melt and a step for integrally forming the regular helical protruding ridge composed of the thermoplastic resin on the surface thereof with another auxiliary extruder.;COPYRIGHT: (C)1994,JPO&Japio