To ensure the quality of heavy plate products as determined by ultrasonic inspection, it is necessary to effectively control defects such as cracks and shrinkage cavities in heavy plates. Generally, some defects such ...To ensure the quality of heavy plate products as determined by ultrasonic inspection, it is necessary to effectively control defects such as cracks and shrinkage cavities in heavy plates. Generally, some defects such as large size cracks exist due to insufficient deformation in the center of traditionally rolled plates. Compared with the traditional rolling process, gradient temperature rolling(GTR) process can effectively increase deformation inside heavy plates. In this study, the effect of GTR on crack healing was analyzed through a comparison experiment with the uniform temperature rolling(UTR). The results show that the GTR process could increase the plastic strain inside the heavy plate and effectively promote the healing process of the preset cracks. The degrees of crack healing at the center and quarter thickness position of the steel plate via GTR were greater than twice those of the plate via UTR. The GTR process can significantly reduce the internal defects of heavy plates and improve the defect detection level of heavy plate products. Also, The GTR process results in the formation of new crystal grains in the crack region, which is crucial to crack healing.展开更多
Baosteel＇ s 5m heavy plate plant was successfully tested on March 1,2005. Since then,the Heavy Plate Plant of Baosteel （hereinafter referred to as ＂the plant＂ ） has been encouraging its employees to study and tra...Baosteel＇ s 5m heavy plate plant was successfully tested on March 1,2005. Since then,the Heavy Plate Plant of Baosteel （hereinafter referred to as ＂the plant＂ ） has been encouraging its employees to study and trace the advanced heavy plate technologies, trying to find out the rules of heavy plate production and its quality control. The plant has gradually mastered this modem heavy plate plant and ensured that Baosteel＇ s production of heavy plates grew year by year,with 1.41 Mt product put in storage in 2007. The plant has focused on developing new technologies and products, meanwhile enhancing its capacity. It has produced a series of plate products, which can be used in manufacturing ship hulls ,pipelines ,bridges ,buildings ,boilers and pressure vessels.展开更多
Analyzed and studied the characters of high strength low alloy steel which contain Mo,Cr,Nb and Ni.etc.Following actual rolling,combining the feature of rolling mode,and exploiting the equipment advantage of 5 m Heavy...Analyzed and studied the characters of high strength low alloy steel which contain Mo,Cr,Nb and Ni.etc.Following actual rolling,combining the feature of rolling mode,and exploiting the equipment advantage of 5 m Heavy Plate Mill,optimized the material design,heating temperature and rolling method, stabilized rolling process of thin alloyed steel,the quality index was advanced.展开更多
This paper describes the benefits, technical difficulties and disadvantages of the current heavy reduction solutions for plate production. For updated plate mills,this paper gives a better idea for the heavy reduction...This paper describes the benefits, technical difficulties and disadvantages of the current heavy reduction solutions for plate production. For updated plate mills,this paper gives a better idea for the heavy reduction control in the rolling process. That is to keep the reduction amount constant in the front-end and back-end sections of the plate and to adopt tapered rolling with variable reduction in the middle section of the plate. This solution （ already applied for a patent） can not only fully utilize the capacity of the mill motors, but also prevent difficulties in plate biting caused by the conventional heavy reduction solutions with excessive draft. This technical solution has been implemented at the 5 m plate mill plant of Baosteel,and industrial tests have proved the feasibility of it. This paper presents and analyzes the industrial test data and proves that the tapered heavy reduction technology can reduce the number of rolling passes. In addition ,this paper looks forward to the future research in this area.展开更多
On the basis of a 5 m plate mill, a 3D rigid-plastic finite element （FE） model was developed to investigate changes of plate plan view patterns during hot rolling process. By analyzing the simulation results of conv...On the basis of a 5 m plate mill, a 3D rigid-plastic finite element （FE） model was developed to investigate changes of plate plan view patterns during hot rolling process. By analyzing the simulation results of conventional rolling processes, it was found that the plate plan view pattern was closely related to broadside rolling ratio. Then, the prediction models for plate plan view patterns were formulated by nonlinear regressive analysis of the simulation results and modified for high accuracy. Based on these models, the broadside compensation rolling method perform- ing at the last pass of broadside rolling phase was designed to decrease plate end crops. Comparing the plate plan view patterns with and without broadside compensation roiling, reduced plate end crops indicate that the broadside compensation roiling model is effective for plate plan view pattern control.展开更多
Taking advantage of the progress of roll-bonding technology, the integrity of the material technology, and the development of the production and examination facilities of all the main carbon steels, stainless steels a...Taking advantage of the progress of roll-bonding technology, the integrity of the material technology, and the development of the production and examination facilities of all the main carbon steels, stainless steels and specialty alloys in Baosteel, the cladded flat new products, which combined both properties of base material and clad material ,have been developed and produced in large quantities. The product categories includes heavy plates with high alloy content and homogeneous distribution in thickness and carbon steel plates cladded with all kinds of stainless steels ,nickel alloys ,and titanium alloys. The double-sided and single-sided cladding hot roiled strips and cold rolled sheets were also commercially produced. Due to the combined properties of both the cladding material and backing material, all products show obvious improvement in properties when compared with solid material. The comparability with the existing production process and equipment laid a very solid foundation for high productivity.展开更多
文摘To ensure the quality of heavy plate products as determined by ultrasonic inspection, it is necessary to effectively control defects such as cracks and shrinkage cavities in heavy plates. Generally, some defects such as large size cracks exist due to insufficient deformation in the center of traditionally rolled plates. Compared with the traditional rolling process, gradient temperature rolling(GTR) process can effectively increase deformation inside heavy plates. In this study, the effect of GTR on crack healing was analyzed through a comparison experiment with the uniform temperature rolling(UTR). The results show that the GTR process could increase the plastic strain inside the heavy plate and effectively promote the healing process of the preset cracks. The degrees of crack healing at the center and quarter thickness position of the steel plate via GTR were greater than twice those of the plate via UTR. The GTR process can significantly reduce the internal defects of heavy plates and improve the defect detection level of heavy plate products. Also, The GTR process results in the formation of new crystal grains in the crack region, which is crucial to crack healing.
文摘Baosteel＇ s 5m heavy plate plant was successfully tested on March 1,2005. Since then,the Heavy Plate Plant of Baosteel （hereinafter referred to as ＂the plant＂ ） has been encouraging its employees to study and trace the advanced heavy plate technologies, trying to find out the rules of heavy plate production and its quality control. The plant has gradually mastered this modem heavy plate plant and ensured that Baosteel＇ s production of heavy plates grew year by year,with 1.41 Mt product put in storage in 2007. The plant has focused on developing new technologies and products, meanwhile enhancing its capacity. It has produced a series of plate products, which can be used in manufacturing ship hulls ,pipelines ,bridges ,buildings ,boilers and pressure vessels.
文摘Analyzed and studied the characters of high strength low alloy steel which contain Mo,Cr,Nb and Ni.etc.Following actual rolling,combining the feature of rolling mode,and exploiting the equipment advantage of 5 m Heavy Plate Mill,optimized the material design,heating temperature and rolling method, stabilized rolling process of thin alloyed steel,the quality index was advanced.
文摘This paper describes the benefits, technical difficulties and disadvantages of the current heavy reduction solutions for plate production. For updated plate mills,this paper gives a better idea for the heavy reduction control in the rolling process. That is to keep the reduction amount constant in the front-end and back-end sections of the plate and to adopt tapered rolling with variable reduction in the middle section of the plate. This solution （ already applied for a patent） can not only fully utilize the capacity of the mill motors, but also prevent difficulties in plate biting caused by the conventional heavy reduction solutions with excessive draft. This technical solution has been implemented at the 5 m plate mill plant of Baosteel,and industrial tests have proved the feasibility of it. This paper presents and analyzes the industrial test data and proves that the tapered heavy reduction technology can reduce the number of rolling passes. In addition ,this paper looks forward to the future research in this area.
文摘On the basis of a 5 m plate mill, a 3D rigid-plastic finite element （FE） model was developed to investigate changes of plate plan view patterns during hot rolling process. By analyzing the simulation results of conventional rolling processes, it was found that the plate plan view pattern was closely related to broadside rolling ratio. Then, the prediction models for plate plan view patterns were formulated by nonlinear regressive analysis of the simulation results and modified for high accuracy. Based on these models, the broadside compensation rolling method perform- ing at the last pass of broadside rolling phase was designed to decrease plate end crops. Comparing the plate plan view patterns with and without broadside compensation roiling, reduced plate end crops indicate that the broadside compensation roiling model is effective for plate plan view pattern control.
文摘Taking advantage of the progress of roll-bonding technology, the integrity of the material technology, and the development of the production and examination facilities of all the main carbon steels, stainless steels and specialty alloys in Baosteel, the cladded flat new products, which combined both properties of base material and clad material ,have been developed and produced in large quantities. The product categories includes heavy plates with high alloy content and homogeneous distribution in thickness and carbon steel plates cladded with all kinds of stainless steels ,nickel alloys ,and titanium alloys. The double-sided and single-sided cladding hot roiled strips and cold rolled sheets were also commercially produced. Due to the combined properties of both the cladding material and backing material, all products show obvious improvement in properties when compared with solid material. The comparability with the existing production process and equipment laid a very solid foundation for high productivity.
