Plate and strip rolling process on-line quality judgment method

Abstract

The invention provides a plate and strip rolling process on-line quality judgment method, and relates to the technical field of rolling automatic control. According to the method, after measured dataare obtained from a thickness measuring instrument, sampling point dividing is carried out again according to the reference length by calculating the sampling length corresponding to sampling points,the standard deviation and the yield of the thickness quality of all parts of a head, a body and a tail of a rolled piece, comparison with the target yield is made, and grades of qualified products and non-qualified products are obtained; and subsequent processing suggestions are further given to the rolled piece in manners of cutting and slitting the head and the tail and the like. The plate andstrip rolling process on-line quality judgment method can conduct comprehensive judgment the thickness quality of the rolled piece, solves the deficiency existing in a traditional thickness determination mode and provides an effective means for online judgment of the thickness quality of hot rolled products.

Description

technical field [0001] The invention relates to the technical field of rolling automatic control, in particular to an on-line quality judgment method for a strip rolling process. Background technique [0002] Hot-rolled products are important basic raw materials for high-end products such as home appliances and automobiles, and can also be used as end products in manufacturing industries such as ships, machinery, and pressure vessels, and are an important support for the development of the national economy. In the hot rolling production process, thickness is an important quality index. With the help of advanced model setting technology and thickness automatic control technology, the thickness control accuracy has reached a high control level. However, in the environment of product specification switching, equipment failure, etc. , will cause the product thickness to fluctuate and the stability will decrease. Therefore, the online monitoring of product quality is particularl...

AI Technical Summary

Problems solved by technology

[0003] At present, product thickness determination generally adopts the method of pass rate statistics, which mainly counts the number of out-of-tolerance sampling points of actual measured data, and calculates its percentage in the total measurement sampling points. If the percentage is less than the target percentage, it is a qualified product, and if the percentage exceeds the target percentage, it is judged as a product. However, in the actual process, this method has the following deficiencies: (1) In general, during the use of hot-rolled products, the irregular parts at the head and tail need to be cut off, so this part of the sampling point needs to be determined during the judgment process. (2) Rising-speed rolling is generally used in the hot rolling process, and the length of the rolled piece corresponding to each sampling cycle is different, and it needs to be judged according to the ratio of the out-of-tolerance length to the total length of the rolled piece; (3) if the out-of-tolerance The position exists in multiple positions on the body of the rolled piece, and fluctuates within the tolerance range. Although the pass rate meets the requirements, the product quality is not accepted by the user; (4) the judgment result is only qualified or unqualified, and no further guidance is given for Subsequent Actions for Judgment Results

Images