CN-121988728-A - 350-Ton large ladle bottom working layer pouring structure and maintenance method

CN121988728ACN 121988728 ACN121988728 ACN 121988728ACN-121988728-A

Abstract

The invention discloses a pouring structure and a maintenance method of a working layer of a large 350 ton steel ladle bottom, wherein the pouring structure of the working layer of the steel ladle bottom comprises an inclined ladle bottom substrate, a slag-resisting area is arranged at the position of the inclined ladle bottom substrate corresponding to a steel ladle nozzle, and the slag-resisting area is a square groove formed on the inclined ladle bottom substrate. The ladle working layer structure is suitable for a large ladle of 350 tons, and the inclined ladle bottom matrix is matched with the slag-resisting area of the square groove during production, so that molten steel can flow to the slag-resisting area at the water gap in an accelerating way, and when molten steel flows to the slag-resisting area, the vertical transition surface of the slag-resisting area can enable the molten steel to reach the slag-resisting area to have a deceleration effect, thereby damaging molten steel vortex formed above the water gap and weakening slag. In the production process, the slag-preventing area is maintained regularly by the maintenance method, so that the slag-preventing area can maintain a good state, the advantage of reducing the casting residue to the greatest extent in the online service period of the working layer at the bottom of the ladle is realized, and the molten steel yield is obviously improved.

Inventors

ZHENG LONGJIE
QIN MEI
ZHUANG SEN
LING HANQING
HUANG GUANJIE
HE ZHIBIN
LUO YUHUI

Assignees

宝钢湛江钢铁有限公司

Dates

Publication Date: 20260508
Application Date: 20260127

Claims (6)

1. The pouring structure of the working layer of the large-scale steel ladle bottom of 350 tons is characterized by comprising an inclined ladle bottom substrate, wherein a slag-resisting area is arranged at the position of the inclined ladle bottom substrate corresponding to a steel ladle nozzle, and the slag-resisting area is a square groove formed on the inclined ladle bottom substrate; the ladle bottom working layer pouring structure is formed by pouring a ladle on the horizontal ground, firstly installing an air brick structure and a water gap pocket brick structure on a ladle bottom permanent layer, then using a sizing block with the height of 100-120 mm to fill up the water gap side of the ladle bottom surface to incline the ladle, then placing a slag prevention area structure mould above the water gap pocket brick of the ladle, pouring stirred ladle bottom working layer pouring materials on the ladle bottom permanent layer, uniformly vibrating by using a vibrating rod, self-leveling by virtue of the ladle bottom working layer pouring materials, enabling the pouring height of the ladle bottom working layer pouring materials to be level with the upper edge of the slag prevention area mould, finally taking out the slag prevention area mould after maintenance for 24 hours, taking down the water gap side sizing block, and placing the ladle on the horizontal ground to obtain the ladle bottom working layer with an inclined ladle bottom base body and a square groove slag prevention area.
2. The pouring structure of the working layer of the bottom of the large 350-ton steel ladle according to claim 1, wherein the side length of the square groove is 600-800mm, and the depth is 60-80mm.
3. The pouring structure of the working layer of the bottom of the large 350-ton steel ladle according to claim 1, wherein the slope of the inclined bottom substrate formed after the pouring material of the working layer of the bottom is self-leveling is 1-3 degrees.
4. A maintenance method for a pouring structure of a working layer of a large 350 ton steel ladle bottom is characterized in that the pouring structure of the working layer of the steel ladle bottom is maintained regularly, and the concrete flow is that after the steel ladle is turned over, the steel ladle is returned to a hot repair station, after the steel ladle is turned over to the horizontal state, a natural gas cleaning gun penetrates through a ladle cover observation hole and extends to a position which is less than 1 meter away from the bottom surface of a slag prevention area, the natural gas cleaning gun is opened to clean the slag prevention area, at the moment, the oxygen pressure is 0.7-1.2Mpa, the natural gas pressure is 0.4-0.7Mpa, the cleaning time is more than 5 minutes, and the cleaning of the slag prevention area is ensured to be clean and the structural shape is kept intact.
5. The method according to claim 4, wherein the cleaning of the slag-preventing area is performed in a sequence from top to bottom, the left half structure is counterclockwise from top to bottom, the right half structure is clockwise from top to bottom, the cleaning is performed along the side wall of the slag-preventing area, the outline of the slag-preventing area is displayed, the inner side wall is cleaned towards the center of the bottom surface of the slag-preventing area, the original depth of the slag-preventing area is maintained, and the side wall of the slag-preventing area and the bottom surface area of the slag-preventing area are cleaned completely without slag adhesion.
6. The maintenance method according to claim 4, wherein the ladle is maintained every 5 times after being returned to the hot repair position or when the amount of the furnace casting slag is more than 7 tons.

Description

350-Ton large ladle bottom working layer pouring structure and maintenance method Technical Field The invention relates to the technical field of steelmaking, in particular to a pouring structure and a maintenance method for a large 350-ton ladle bottom capable of improving molten steel yield. Background The ladle receives the molten steel from the converter, conveys the molten steel to a refining process for alloying, uniform composition and the like, and conveys the molten steel to continuous casting for casting. The ladle is a high temperature vessel for holding molten steel in steelmaking-continuous casting production. In the continuous casting process, after ladle casting, as the casting is carried out, the ladle casting end stage and the molten steel surface drop to a certain height, due to the combined action of the factors such as Coriolis force caused by earth rotation, circulation induced by uneven flow fields, potential energy of the molten steel in the fluid outflow process and the like, the molten steel generates vortex to cause slag rolling of the molten steel, part of ladle slag enters the tundish, so that the molten steel in the tundish is polluted, and a ladle slag discharging detection control system is commonly used for monitoring in steel factories in order to avoid similar events. After the slag detection system alarms, the ladle slide plate is automatically closed, the residual molten steel amount in the ladle is about 5-7 tons or more, and the molten steel yield is reduced. At present, in order to reduce the ladle casting residue amount, the molten steel yield is improved. The prior art has an optimized ladle bottom structure, such as the Chinese patent with publication number of CN110756789A, discloses a ladle bottom and a method for reducing the casting residue of an IF steel ladle, which mainly comprises the steps of arranging a fan-shaped slag-resisting area structure, wherein the transition surface of the fan-shaped slag-resisting area is an arc surface or a slope surface, the structure of the non-slag-resisting area at the ladle bottom is a horizontal plane, as the number of times of steel receiving of the ladle increases, steel tapping flows impact the ladle bottom to cause melting loss and peeling of casting materials at the ladle bottom to form pits, molten steel is easy to accumulate in the pits at the ladle bottom in the later stage of ladle casting, and cannot flow to the slag-resisting area, so that the problem of large casting slag quantity still exists. In addition, the transition surface of the fan-shaped slag-resisting area is designed to be an arc surface or a slope surface, and the structure is easy to accelerate molten steel flowing through the area to flow to a ladle nozzle, so that the slag quantity of the molten steel is increased, the drop amplitude of the casting residue quantity is limited, and the risk of poor quality of the molten steel is increased. With the increase of the use times of the ladle, the structure of the ladle bottom slag-resisting area is affected by molten steel scouring, chemical erosion and the like, so that the advantages are gradually weakened, and the original structure cannot be maintained in the online use period of the ladle. Especially for a large ladle of 350 tons, more ladle casting residues still exist due to the large diameter of the ladle bottom. Disclosure of Invention The invention aims to provide a pouring structure of a working layer at the bottom of a large 350 ton steel ladle and a method for maintaining the structure, under the premise of ensuring the controlled and safe use of the residual thickness of the steel ladle, the method realizes that the steel ladle of 350 tons reduces the amount of casting residue and residual steel, maintains the structure of a ladle bottom slag-resisting area in the online use process of the steel ladle, and remarkably improves the yield of molten steel. In order to achieve the technical aim, the invention adopts the following technical scheme that the pouring structure of the working layer of the large-scale steel ladle bottom of 350 tons is characterized in that the pouring structure of the working layer of the steel ladle bottom comprises an inclined ladle bottom matrix, a slag-resisting area is arranged at the position of the inclined ladle bottom matrix corresponding to a steel ladle nozzle, and the slag-resisting area is a square groove formed on the inclined ladle bottom matrix; the ladle bottom working layer pouring structure is formed by pouring a ladle on the horizontal ground, firstly installing an air brick structure and a water gap pocket brick structure on a ladle bottom permanent layer, then using a sizing block with the height of 100-120 mm to fill up the water gap side of the ladle bottom surface to incline the ladle, then placing a slag prevention area structure mould above the water gap pocket brick of the ladle, pouring stirred ladle bottom working layer pouring materia