Improvement of Longitudinal Surface Cracks in CC Slabs by Air-water Mist Cooling Method

Kono, Takashi; Shima, Takatsugu; Kuwabara, Tatsuro; Yamamoto, Takao; Wake, Makoto; Tsuneoka, Akira

doi:10.2355/tetsutohagane1955.68.13_1792

Cited by 3 publications

(2 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Also, application of this air-mist cooling method has made it possible to realize slack cooling in the secondary cooling zone, which has proved to be of a great help in preventing defects in medium carbon steels. [40][41][42][43][44][45][46] To utilize this nozzle's feature of generating a very fine mist over a wide range of water flowrates, however, a high air-to-water ratio is necessary, meaning a high air consumption rate and a correspondingly high running cost. Therefore, fine control of air-to-water ratio to the minimum requirement in each of the cooling regions is being practiced.…”

Section: Technologies For Preventing Surface Longitudinal Cracksmentioning

confidence: 99%

Technologies that have made direct concatenation of continuous casting and hot rolling possible.

Tsubakihara

1987

ISIJ Int.

View full text Add to dashboard Cite

Section: Technologies For Preventing Surface Longitudinal Cracksmentioning

confidence: 99%

Technologies that have made direct concatenation of continuous casting and hot rolling possible.

Tsubakihara

1987

ISIJ Int.

View full text Add to dashboard Cite

“…Secondary cooling is an important process in continuous casting in the steelmaking division from the viewpoints of stable industrial operation and the quality of cast slabs. Historically, spray nozzles have been developed from hydraulic spray nozzles to mist spray nozzles to prevent clogging of the nozzle tip and surface cracks of cast slabs . Table shows a comparison of the merits and demerits of hydraulic and mist spray nozzles based on reports concerning spray nozzles in the secondary cooling process.…”

Section: Introductionmentioning

confidence: 99%

Effect of Spray Thickness and Collision Pressure on Spray Cooling Capacity in a Continuous Casting Process

Tsutsumi¹,

Kubota

Hosokawa³

et al. 2018

steel research int.

View full text Add to dashboard Cite

Recently higher slab cooling capacities have been needed to cope with high speed casting operation over the wide range of water spray rates in the secondary cooling process. However, there are few reports on the cooling capacity of the secondary cooling process, especially the spray thickness and the collision pressure in the casting direction. In this study, laboratory experiments on the cooling capacities of hydraulic and mist spray nozzles are carried under various conditions by developing several kinds of spray nozzles. From the experimental results, in order to achieve a high cooling capacity in a spray nozzle, it is important to select the proper spray thickness and collision pressure when designing the nozzle. As a result, the following new estimation equation for the total heat transfer coefficient is proposed based on a new parameter, that is, the product of spray thickness (Ld) and collision pressure (P). have.=6.21×Ld×P+397. This equation can be used to estimate the cooling capacity of spray nozzles without carrying out experiments with a heated sample plate.

show abstract

Development of Hard Secondary Cooling by High-pressure Water Spray in Continuous Casting

Ito¹,

Murai²,

Miki³

et al. 2011

ISIJ Int.

View full text Add to dashboard Cite

Cooling intensity in secondary cooling is an important factor for achieving high-speed casting. In this study, we investigated the effects of the hydraulic pressure and water flow rate of a cooling water spray on cooling intensity, and developed a more efficient secondary cooling system with a high-water pressure spray. In laboratory experiments, a test plate was heated to 1 273 K and then cooled below a certain temperature by one nozzle under various experimental conditions. The heat transfer coefficient was estimated using the temperature data from thermocouples 3 mm below the cooled surface. The average heat transfer coefficient with a hydraulic pressure of 5 MPa was 2.8 times larger than that of a conventional water spray nozzle at the same water flow rate. On the basis of the laboratory results, plant trials were carried in the Kurashiki No. 2 CCM at JFE West Japan Works. A high-pressure water supplying device (maximum 5 MPa) with high pressure type nozzles was installed in one segment at a position from 2.5 to 4.0 m below the meniscus and the water flow rate of the high-pressure spray was the same as that of the conventional one. It was confirmed that casting speed was increased by 30% without any inner cracks or surface cracks for several steel grades. In addition, the measurements of slab surface temperature were in good agreement with the thermal calculation results from the laboratory heat transfer coefficient data.

show abstract

Improvement of Longitudinal Surface Cracks in CC Slabs by Air-water Mist Cooling Method

Cited by 3 publications

References 1 publication

Technologies that have made direct concatenation of continuous casting and hot rolling possible.

Technologies that have made direct concatenation of continuous casting and hot rolling possible.

Effect of Spray Thickness and Collision Pressure on Spray Cooling Capacity in a Continuous Casting Process

Development of Hard Secondary Cooling by High-pressure Water Spray in Continuous Casting

Contact Info

Product

Resources

About