Laser Mill Scale Removal for Tubular Surface Integrity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for removing mill scale from steel tubulars, such as shot blasting and sand blasting, pose safety risks and environmental concerns due to generated wastes, and are inefficient compared to the proposed laser ablation system.
Innovation Solution
A mill scale removal system utilizing a laser ablation system with adjustable stands and a rotation assembly, where a laser source outputs a controlled laser beam to remove mill scale without altering the tubular material's properties, combined with a suction tube to collect debris, facilitating both internal and external surface cleaning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If shot blasting or sand blasting is used to remove mill scale, then the mill scale can be removed from the tubular surface, but safety risks increase and environmental harm occurs due to generated wastes
Solution Approach 1:
The patent replaces the mechanical shot blasting and sand blasting systems with a laser-based ablation system. The laser beam removes mill scale through thermal vaporization rather than mechanical impact, eliminating the need for abrasive materials and reducing safety hazards associated with high-velocity particle projection and waste disposal
Solution Approach 2:
The patent changes the removal mechanism from mechanical force to thermal energy by using laser radiation. The laser parameters (wavelength, power, pulse duration) are optimized to selectively vaporize mill scale while preserving the underlying metal, achieving effective removal without the harmful effects of conventional mechanical methods
2Reliability
If conventional blasting methods are used, then mill scale removal can be achieved, but waste generation occurs in the form of gases and solid particles
Solution Approach 1:
The patent eliminates the use of abrasive materials by replacing mechanical blasting with laser ablation. The laser beam directly vaporizes the mill scale into gas and fine particles that can be controlled and contained, eliminating the need for solid abrasive waste handling and disposal systems
Solution Approach 2:
The patent converts the potentially harmful laser-generated vapor and particles into a controllable process by using suction nozzles to capture the debris immediately at the treatment zone. The captured material can be filtered and disposed of in a controlled manner, transforming what would be uncontrolled environmental pollution into a manageable waste stream
3Productivity
If high laser intensity is used to remove mill scale, then removal efficiency increases, but the tubular material properties may be altered
Solution Approach 1:
The patent applies laser parameters that create localized heating only at the mill scale layer interface. The laser wavelength and pulse duration are selected to be selectively absorbed by the mill scale while minimizing penetration into the base metal, ensuring that only the unwanted oxide layer is removed without affecting the structural properties of the tubular
Solution Approach 2:
The patent uses pulsed laser operation rather than continuous wave laser. The pulsed regime allows for controlled heating and cooling cycles, enabling mill scale removal through repeated thermal stress and vaporization while preventing excessive heat accumulation that could alter the base metal properties
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
The system provides a safer, more efficient method for removing mill scale, ensuring the tubular's material integrity while minimizing environmental impact by effectively removing mill scale without altering the tubular's properties and reducing waste generation.
Implementation Method 1
a laser source configured to output a laser having a laser intensity sufficient to remove at least one mill scale layer formed on the inner radial surface or the outer radial surface at a particular laser ablation threshold
Implementation Method 2
the at least one laser sub-assembly includes a suction tube configured to vacuum the removed at least one mill scale layer away from the inner radial surface or the outer radial surface
Data Source
AI summary
A mill scale removal system includes adjustable stands including vertical arms, horizontal arms coupled to the vertical arms, and rollers coupled to the horizontal arms and configured to support a tubular by contacting engagement with an inner radial surface or an outer radial surface at or near terminal ends of the tubular; a laser ablation system that includes at least one laser sub-assembly mounted to a rod and a first motor driveably coupled to the rod; and a rotation assembly including a second motor, a drive rod coupled to the second motor, and a rotation roller coupled to the drive rod and configured to contactingly engage the outer radial surface of the tubular.