Tempered Steel Pipe Diameter Control via Pre-Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing tempered, hot-rolled steel pipes face challenges in achieving precise diameter tolerances and material properties due to grain growth and expansion during tempering, leading to increased production costs and energy consumption, especially when using sizing mills for diameter adjustments.
Innovation Solution
A method that adjusts the finished diameter of steel pipes after rolling based on anticipated growth during tempering, utilizing controlled cooling rates and quenching parameters to achieve target diameters within specified tolerances without the need for sizing rolling, allowing for more economical production and reduced energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a sizing mill is used to adjust diameter after tempering, then diameter precision is improved, but production cost and energy consumption increase
Solution Approach 1:
The invention calculates and sets the rolling mill's finished diameter in advance to account for anticipated diameter growth during tempering. By performing this preliminary calculation and adjustment before the tempering process, the patent eliminates the need for subsequent sizing operations, thereby reducing energy consumption while maintaining diameter precision.
Solution Approach 2:
The invention extracts and eliminates the sizing mill operation from the production process. By taking out this energy-intensive step and replacing it with a calculation-based diameter adjustment in the rolling stage, the patent achieves the same diameter precision without the associated energy consumption and production costs.
2Strength
If tempering is performed to achieve required mechanical properties, then material strength is improved, but diameter growth occurs requiring additional processing
Solution Approach 1:
The invention performs a preliminary calculation of the expected diameter growth during tempering and adjusts the rolling mill's finished diameter accordingly before tempering occurs. This advance preparation ensures that after tempering, the pipe achieves both the required mechanical properties and the target diameter tolerance without needing additional correction steps.
3Manufacturing precision
If the rolling mill produces pipes with adjusted finished diameter to compensate for tempering growth, then final diameter precision is improved, but the rolling process complexity increases
Solution Approach 1:
The invention implements a feedback mechanism where the expected diameter growth from tempering is calculated based on material properties and tempering parameters, and this information is fed back to adjust the rolling mill's finished diameter setting. This closed-loop approach achieves high final diameter precision through a straightforward calculation and adjustment process rather than complex equipment modifications.
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 the production of steel pipes with precise diameter tolerances and improved material properties while minimizing production costs and energy use, allowing for the rolling of diverse pipe types with a single finished diameter without extensive mill conversions.
Implementation Method 1
heating to austenitization temperature
Implementation Method 2
grain growth takes place in the structure of the steel, which leads to an increase in the diameter of the pipe
Implementation Method 3
the pipe expands during heating
Data Source
AI summary
A method for producing a tempered, seamlessly hot-rolled steel pipe includes heating a hollow block to forming temperature and rolling the heated block in a rolling mill to form a pipe with a finished diameter after rolling. Subsequently, the pipe is tempered with appropriate tempering parameters after rolling whereby the diameter of the pipe increases during tempering. The finished diameter of the pipe to be tempered after rolling in the rolling mill is adjusted as a function of a value of the growth in diameter of the pipe during tempering.