The method of producing 4mm thick q345de steel plate on wide plate rolling mill

Abstract

The invention relates to a method for producing a low-alloy and high-strength Q345DE steel plate with the thickness of 4 mm on a wide and thick plate rolling machine. The technology paths include material selecting, cogging and heating, descaling, cogging and rolling, cooling, primarily-rolled blank finishing (including checking and disconnecting), composite welding (a composite blank), checking and warehousing. The composite blank is subjected to heating, descaling, rolling (finished product rolling), cooling, finishing (including vertical separated cutting of the steel plate), appearance checking, sampling, physical and chemical checking, judging and warehousing again. The reasonable Q345DE chemical component blank is selected, the thickness and length of a rolled piece are scientifically selected, the blank is subjected to composite welding, heating, rolling, finishing, examining and checking are conducted, and the thickness of the produced finished steel plate is 4.0 mm. The product performance, size, and surface quality can completely meet the GB / T1591 product standard requirements. The product can fill up the vacancy that domestic and oversea wide and thick plate rolling machines of 3m or above cannot roll thin-specification low-alloy steel plate products.

Description

technical field [0001] The invention belongs to the technical field of steel plate rolling, and in particular relates to a method for producing thin-gauge, low-alloy, high-strength Q345DE on a wide-thick plate rolling mill. Background technique [0002] Wide and thick plate rolling mills over 3 meters (including) mainly produce steel plates with a thickness of more than 8mm, while thin steel plates below 8mm are usually rolled on a hot continuous rolling mill and obtained after Kaiping treatment. For low-alloy high-strength steel plates and special-purpose plates such as marine plates and pressure vessel plates, there are many post-welding operations, and the steel plates are mostly required to be flat plates. Because the shape of the coiled plate is difficult to be guaranteed after flattening; and the width of the coiled plate is narrow, there are problems of large welding operations and high costs in the later stage. [0003] At present, for wide and heavy plate rolling e...

AI Technical Summary

Problems solved by technology

Because the shape of the coiled plate is difficult to be guaranteed after being flattened; and the width of the coiled plate is narrow, there are problems of large welding operations and high costs in the later stage

[0003] At present, for wide and heavy plate rolling enterprises at home and abroad, the rolling thickness limit specification of the rolling mill is 6mm, especially for the medium plate with a thickness of 5mm and below, which has exceeded the limit of the production capacity of the wide and heavy plate rolling mills at home and abroad; Difficult. During the rolling process, problems such as wave shape, camber, frame scraping, and rolling waste are prone to occur. The production accident rate is high, and it is difficult to form mass production.