To improve the surface quality of wire rods, billets are descaled by shot blasting, and inspected for surface flaws by magnetic particle tester. Grinding machines are used to remove any surface flaws. In addition, continuos ultrasonic testing is conducted to guarantee the prime quality.
Reheating furnace is carefully examined, to produce prime materials in customers’ desired properties. To prevent decarburization, billets are preheated at a low temperature, followed by a full heating process, to suit a right temperature for billets’ rolling procedure. The rolling speed and fuel-to-air ratio in the reheating furnaces are fully controlled.
The rolling procedure must be carefully controlled, to adjust temperature, pressure and deformation rate to form customers’ desired characteristics. Moreover, surface roughness, sizes, and deviations are subject to adjustment to prevent any flaws.
Precise control of temperature, air volume, speed, opening and closing of slow-cooling sections are all variables that affect physical properties. Uniform fastcooling methods are used for high carbon steel wires, and slow-cooling method is applied for alloy and lowcarbon steel.
Samples of leading and trailing edges of wire rods are collected for quality assurance tests, which include surface flaw detection. Once wire rods are deemed prime, products are then packaged and tagged to clients’ requirements.