A Production Process for Reducing Cracks in Billet-Rolled Steel Plates

Abstract

The invention discloses a production process for reducing cracks on a steel plate formed by rolling a steel billet. Through the technical scheme, the cracks on the surface of the steel plate formed byrolling the steel billet through a hot charging and hot conveying process can be effectively reduced, and meanwhile the internal flaw detection quality of the steel plate formed by rolling the continuous casting steel billet is also improved. The production process comprises the specific method that after the continuous casting steel billet passes a straightening point, water mist cooling nozzlesare additionally arranged on a horizontal pulling-straightening section, so that the surface of the steel billet is cooled rapidly, the steel billet structure complete the process that austenite is transformed into ferrite and pearlite rapidly in an accelerated mode, and the problems that in a traditional hot charging and hot conveying process, a two-phase region or an austenite region is heated,consequently, grains are coarsened, and in the rolling process, the rolling propagating cracks are formed because of the low plasticity are avoided. Compared with the prior art, not only is the hot charging rate increased, but also the surface cracks are reduced by a large margin. The production technical scheme is quite effective for the cracks on the surfaces of the low-alloy steel plates and the micro-alloy steel plates.

Description

Technical field [0001] The invention relates to the technical field of steel slab rolling steel plate technology, in particular to a production process for reducing cracks in steel slab rolled steel plate. Background technique [0002] In the context of severe surplus in the steel industry and increasing competition pressure, reducing costs, improving quality, and reducing capital pressure are the inevitable choices of the steel industry. At present, there are two types of continuous casting billet loading in the production of medium and heavy plates, one is direct hot charging and hot delivery of billets off the line, and the other is loading billets after slow cooling off the line. Although the first hot charging and hot delivery process has a certain energy saving effect, a series of problems such as serious surface cracks and deterioration of steel plate performance generally occur in the actual production process, especially for microalloy and low-alloy steel plates. The cr...

AI Technical Summary

Problems solved by technology

Although the first hot charging and hot delivery process has a certain energy-saving effect, a series of problems such as serious surface cracks and deterioration of steel plate performance generally occur in the actual production process, especially for micro-alloy and low-alloy steel plates. The crack rate of loaded billets is more than 20%, which seriously reduces the quality of steel plates and increases production costs

The quality of the cold-packed steel plate is better, but the steel billet needs to be stacked for 6-72 hours, and there are problems such as a backlog of steel billets, a large amount of capital occupied, and increased energy consumption.