Work Roll Thermal Control via Pre-Heating Sprays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rolling mills face challenges in maintaining uniformity of metal sheet or plate thickness due to transient thermal behavior of work rolls during startup and material changes, leading to wastage and increased production costs.
Innovation Solution
The use of work face heating sprays to pre-heat and thermally stabilize work rolls, combined with a control system for adjusting thermal crown, reduces downtime and waste by ensuring consistent temperature and flatness across the rolls.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If work rolls are heated using traditional startup material, then work rolls reach operating temperature, but production time increases and material waste occurs
Solution Approach 1:
The heating spray system applies heat to the work rolls before metal stock is fed through the rolling mill, pre-heating the rolls to operating temperature in advance. This preliminary thermal conditioning eliminates the need to heat rolls during production, reducing startup time and eliminating scrap material that would otherwise be required for the heating process
2Temperature
If work rolls are heated using startup material, then work rolls reach operating temperature, but material waste increases
Solution Approach 1:
The heating spray system pre-heats work rolls before production begins, eliminating the need to consume startup material that would otherwise be required to bring rolls to operating temperature. This preliminary heating action converts material-based heating into a spray-based thermal process, eliminating scrap generation
Solution Approach 2:
The invention replaces the mechanical process of heating rolls through friction from metal stock with a thermal spray system that directly applies heated liquid or gas to the roll surfaces. This substitution eliminates the need for consumable startup material while achieving the same thermal conditioning objective
3Stability of the object's composition
If heating sprays are applied uniformly across work rolls, then thermal crown is stabilized, but control flexibility decreases
Solution Approach 1:
The heating spray system divides the work roll surface into multiple independently controllable zones, allowing different spray rates and temperatures to be applied to different sections of the roll. This segmentation enables precise control of thermal crown profiles while maintaining overall thermal stability, providing both stability and adaptability simultaneously
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables faster startup, reduced scrap, and improved product quality by stabilizing thermal crown and camber, allowing for more efficient processing and reduced material wastage.
Implementation Method 1
a work face heating spray... The heated liquid medium, or heatant, may be sprayed across the face of the work roll
Implementation Method 2
The heated liquid medium, or heatant, may be sprayed across the face of the work roll to build up and stabilize thermal crown
Data Source
AI summary
Systems and methods for using full-width hot sprays to pre-heat rolling mills prior to processing of metal sheet or plate are described herein. The hot sprays may be individually controlled. Using hot sprays can allow the rolling mill to reach operating temperature and achieve a desired thermal crown so that metal sheet or plate may be processed immediately within tolerances for flatness and gauge accuracy. Pre-heating of rolling mills can eliminate the need of the rolling mill to operate in a transitional period of work roll heating and can increase efficiency by eliminating or reducing scrap material and mill downtime. Hot sprays may also be incorporated with existing coolant systems to provide thermal control systems for rolling mills with bi-directional temperature controls.