Q1 How to select a supplier of mill rolls?

Q1 How to select a supplier of mill rolls?

A1: When selecting a supplier of mill rolls, we should consider various aspects of a supplier such as roll material, hardware equipment, technical capacity, quality control, etc. The below outlines major points for inspecting a supplier.

1. Roll material. Please check whether it is scrap smelting or iron powder smelting, a supplier of work rolls must has capability of electroslag-remelting process.

2. Forging equipment. Please check whether the forging ratio can be achieved, forging ratio of work rolls must be greater than or equal to 3, and forging ratio of backup rolls must be approximately equal to 4.

3. Heat treatment process. Please check whether there is a general normal process of tempering and quenching, quenching methods include scanning quenching, integral quenching, medium frequency quenching, dual frequency quenching, etc., which needs to be optimized according to the material of work roll and the requirements of the rolling mill.

4. Cold processing equipment. Please check whether the machining equipment can meet the technical requirements of the drawings provided by our company, the roll accuracy directly affects the speed and output of the rolling mill.

5. Inspection equipment. Please check whether it has the ability of chemical composition analyzer, acid leaching test, metallographic detector, high and low magnification and non-metallic inclusions detection, mechanical properties and hardness detection, etc. Roll inspection includes UT inspection, surface wave inspection, radial ultrasonic inspection, surface coloring inspection, magnetic particle inspection and eddy current inspection. Mechanical dimensional inspection includes drawing dimensions as well as form and position tolerances and surface quality inspection. Every test is important and will affect the quality of the final product, and suppliers must be strictly audited.