Rotating Submerged Nozzle for Slab Casting Flow Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional slab continuous casting apparatuses face challenges in achieving stable rotation and stirring of molten metal, particularly when the discharge angle of molten metal needs to be arbitrarily changed during casting, leading to insufficient rotational flow and increased inclusions around discharge holes, which affects the quality of ingots.

Innovation Solution

A slab continuous casting apparatus with a discharge-direction changing mechanism that allows for arbitrary adjustment of the discharge angle of molten metal, incorporating a submerged-nozzle quick replacement mechanism and a drive mechanism to change the discharge direction, ensuring proper rotational flow and preventing inclusions deposition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a fixed submerged nozzle is used for molten metal discharge, then the apparatus structure is simple, but the discharge angle cannot be adjusted arbitrarily during casting, resulting in insufficient rotational flow and inadequate stirring effect

Engineering Contradiction:

Improveadjustability of discharge angleVSAvoidcomplexity of discharge mechanism

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The submerged nozzle is designed with rotational capability, transforming from a fixed static structure to a dynamic adjustable one. The nozzle can rotate around its axis to change the discharge angle arbitrarily during casting, enabling adaptive control of molten metal flow direction to achieve desired rotational flow patterns in the mold.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The discharge mechanism is segmented into a rotatable nozzle component and a fixed support structure. This segmentation allows the nozzle to be independently rotated to adjust discharge angles while maintaining the stability of the overall apparatus, resolving the conflict between adaptability and structural simplicity.

Inventive Principle:

Principle #1Segmentation

2Reliability

If the discharge angle is fixed, then the mechanism is simple and reliable, but inclusions deposit around discharge holes when mold width or thickness changes, affecting ingot quality

Engineering Contradiction:

Improvestability of discharge systemVSAvoidinclusions deposition

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The system incorporates feedback control where the discharge angle is adjusted in response to changes in mold dimensions or casting conditions. This feedback mechanism prevents inclusion deposition by dynamically optimizing the discharge angle to maintain proper flow patterns, thereby preserving reliability while eliminating harmful effects.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The discharge angle parameter is made variable rather than fixed. By changing this parameter arbitrarily during casting based on mold width or thickness requirements, the system prevents inclusion deposition around discharge holes while maintaining stable and reliable operation.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If conventional submerged nozzles are used without rotation capability, then the device is simple and inexpensive, but rotational flow cannot be generated effectively to stir molten metal in large cross-sectional slabs

Engineering Contradiction:

Improvestirring effect efficiencyVSAvoidcomplexity of nozzle mechanism

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The rotational flow is generated through periodic or continuous rotation of the submerged nozzle during molten metal discharge. This rotational motion creates the necessary stirring effect in the mold, improving productivity by effectively mixing the molten metal and preventing defects.

Inventive Principle:

Principle #19Periodic action

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 apparatus ensures stable rotation and stirring of molten metal, maintaining optimal discharge angles even when mold width or thickness changes, reducing inclusions and improving ingot quality by enabling continuous adjustment of discharge directions.

Implementation Method 1

a method in which, for example, an electromagnetic stirrer is provided near a cooling mold or on a back face of a cooling mold and molten metal is stirred by utilizing electromagnetic force

Methodology Applied

Scientific EffectElectromagnetic force: Lorentz Force

Data Source

PatentUS10029303B2Slab continuous casting apparatus

Publication Date: 2018.07.24 SHINAGAWA REFRACTORIES CO LTD

AI summary

The invention provides rotating a submerged nozzle during casting to arbitrarily change the discharge angle of molten metal, causing the molten metal in the mold for slab to be rotated and stirred. A slab continuous casting apparatus according to the invention supplies molten metal from a tundish to a water-cooled mold for slab through at least an upper nozzle, a slide valve and a submerged nozzle and solidified the molten metal and provided with a submerged-nozzle quick replacement mechanism. The slab continuous casting apparatus further includes a discharge-direction changing mechanism capable of arbitrarily changing discharge angle of the molten metal as viewed in a horizontal cross section, during casting, the discharge-direction changing mechanism being provided between a slide valve device for opening and closing the slide valve and the submerged nozzle.