PURPOSE: To simply bend a color coated steel reinforcement at predetermined angles and prevent a coated portion from peeling off by using, a rubber roller on whose metal surface a rubber layer, consisting of polyether polyurethane rubber whose hardness is 65-80° (Shore hardness D), is formed.
CONSTITUTION: Polyether polyurethane rubber is selected as a rubber layer, and the one whose hardness is 65-80° (Shore hardness D) is used. Polyurethane rubber having a specific hardness is regulated by making polyether polyol and polyisocyanate react under the existence of a bridging agent. As for a method to bend a steel reinforcement 1 in color coating by means of rubber rollers, the steel reinforcement 1 is mounted on steel reinforcement receiving stands 4 between fixed fulcrum rollers 2 and rotatable dynamic point rollers 3, and rotation in arrow directions is conducted while the steel reinforcement 1 is being pressurized by means of dynamic point rollers 3 with fulcrum rollers 2 as centers. The steel reinforcement 1 is bend gradually in response to the rotation and movement of dynamic point rollers 3, and when it is bent at desired angles, the rotation of dynamic point rollers 3 is stopped. Thus, the coating of the steel reinforcement is not peeled off.
YAMASHITA ARATA