A reducing and sizing production line and its production method

Abstract

The invention discloses a reducing and sizing production line and a production method thereof. According to the production line, a pinch roll is arranged in front of a gripping shear used for reducing and sizing and is close to the gripping shear to the greatest extent, and a hot metal detector is arranged in front of the pinch roll. The pinch roll used for reducing and sizing generally adopts two types of clamping operation modes which are head clamping and whole clamping; the whole clamping or head clamping mode is adopted in the condition of passing of a reducing and sizing mill; the whole clamping mode is adopted by the pinch roll for reducing and sizing in the condition of rolling of the reducing and sizing mill. The reducing and sizing production line can reduce the shake of a rolled piece in a water tank or a soaking zone, ensures that the rolled piece is smoothly bitten with the reducing and sizing mill, avoids steel from being piled in a finish rolling or reducing and sizing waste tank, meanwhile can reduce the abrasion of a water tank nozzle and a guide slot of the soaking zone, ensures that the rolled piece is uniformly cooled in an identical section, eliminates the situation that zebra stripe is produced on the surface of the rolled piece, and reduces out-of-tolerance turns of head and tail of a finished product.

Description

technical field [0001] The invention belongs to the technical field of steel rolling production, and relates to a high-speed wire rod production line and a rolling production process thereof, in particular to a reducing and sizing production line and a production method thereof. Background technique [0002] The common technological process of high-speed wire rod production line: loading of hot and cold billets → conveying and weighing (→ rejecting unqualified) → pushing steel into the furnace → heating → descaling after exiting the furnace (→ rejecting unqualified) → rolling by rough rolling mill → l# shearing Cutting head and tail→rolling in the middle rolling mill→2# flying shear head and tail→rolling in the pre-finishing mill (water cooling in the rolling mill)→pre-water cooling→3# shearing head and tail→rolling in the non-twist finishing mill (water cooling in the rolling mill) )→Water cooling→pinch feeding, silk spinning→coil loosening control cooling→coil collection→c...

AI Technical Summary

Problems solved by technology

[0004] When using reduction and sizing production, some large-scale products are rolled directly from the outlet of intermediate rolling and pre-finishing to the reduction and sizing unit for rolling. Excessive size and loss of tension at the head and tail are likely to cause process failures such as excessive wear of the nozzle and guide groove of the water tank, stacking of steel in the reducing and sizing mill, "zebra pattern" on the surface of the rolled piece, and too many out-of-tolerance turns at the end of the finished product; in order to improve the strength of the finished product The TMCP controlled rolling and controlled cooling production process adopted based on the comprehensive mechanical properties increases the cooling water pressure and water volume of the water tank, so that the resistance of the rolled piece, especially the threaded steel bar, in the water tank becomes larger, and it is simply sent out to the reduction by the finishing mill. diameter rolling or directly sent to the pinch roll in front of the laying machine will easily cause piles of steel, which is difficult to meet the needs of modern production; for the arrangement of 10+2 or 10+4 finishing mills, although it is possible to throw off the reducing and sizing mills when necessary Directly use the finishing mill to produce most of the steel types, but the distance between the finishing mill and the pinch roll before the laying machine is far away during the reduction and sizing process, which will cause large vibrations in the rolled piece, and loss of tension at the head and tail will also cause water tank nozzles Faults such as excessive wear and tear of the guide groove, piled steel in the water cooling line, piled steel in the finishing mill, disordered silk spinning, etc.

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