Quality Control of Prestressed Steel Wires on Raw Materials
The steel carbon content of prestressed steel wire is generally between 0.6% and 0.90%, which should meet the relevant national standards. The diameter of the wire rod is φ6.5~14.0mm, and the metallographic structure of the wire rod is mainly sorbite, and there should be no martensite, reticular cementite and structures harmful to performance.
The quality control of prestressed steel wire on raw materials is mainly the following two aspects.
1. Size control
Control the rolling temperature so that the rolling temperature of the same batch tends to be consistent, and minimize the dimensional fluctuation of the rolled piece caused by the temperature change affecting the deformation resistance and width. Implement micro-tension rolling to minimize the influence of rolling tension. Optimize the pass design of the roll, and enhance the function of the pass system in the rolling process. It adopts the sixth-generation Morgan finishing mill and is equipped with ORBIS optical diameter measuring instrument to detect wire diameter deviation, ellipticity and other indicators on-line.
2. Surface quality
Implement billet grinding, control billet quality, remove various defects on the billet surface, and prevent surface defects such as scars, pits, folds, cracks, and inclusions from being brought into the wire rod. Avoid deep grooves caused by improper handling of billets and folds when rolling wire rods. Thoroughly remove the head and tail of the billet to avoid various defects such as shrinkage cavities, looseness, delamination, and inclusions from being brought into the wire.