Iron and steel industry is the base of the country economy. It is the important support of the social developing, and is the important basic industry of the modern economic. This paper studies the rolling mechanical model of rolling process control, fluid stress model, rolling torque model and the temperature change models. And put forward an on-line modeling method of rolling mill based Least-...

In the flat products steel industry, the hot rolling mill transforms the incoming slabs in a thin coil which then can be processed to obtain the final products. Thickness is reduced by pulling the plate between two parallel rolls while moving the upper work roll. The effect of uneven thickness at both sides can produce deviations in the longitudinal direction of the slab, which have to be manua...

A communication procedure for communicating scheduling expert systems based on fuzzy set theory is proposed. Fuzzy sets are used to express and to exchange constraints and their possible relaxations with other scheduling systems that can interpret these constraints. The procedure is intended to optimize the global evaluation among the communicating systems. An example from steel industry is tak...

The Hot Strip Mill Production Scheduling Problem is a hard problem that arises in the steel industry when scheduling steel coil production. It can be modeled as a generalization of the Prize Collecting Traveling Salesman Problem with multiple and conflicting objectives and constraints. In this paper we formulate this problem as a mathematical program and propose a heuristic method to determine ...

During the manufacturing process in a steel mill, the chemical composition and quality of raw-iron, steel and slack has to be checked several times. The organization of the corresponding list of operations can be classified as a hybrid flow shop scheduling problem with jobs arriving over time and the objective is to minimize the total weighted completion time. Since this problem is known to be ...

Production of thin steel strips with 0.18-0.26 mm thickness is about 0.75 of annual production of the two stand reversing cold mill, while its efficiency is 60%. This is due to the fact that after montaging the grinded work rolls, rolling thin steel strips (with thicknesses less than 0.18 millimeters) is unavailable. Initially, unsuitable surface roughness, the friction between rolls and the st...

The steel mill slab design problem from the CSPLIB is reallife problem from the steel industry. Finding optimal solutions to this problem is difficult. Existing constraint programming approaches can solve problems up to 30 orders. We propose a strong constraint programming model based on logical and global constraints. By designing a specific strategy for variable and value selection, we are ab...

An architecture and a procedure for communicating scheduling expert systems based on fuzzy set theory is proposed. Fuzzy sets are used to express and to exchange constraints and their potential relaxation with the cooperating scheduling system that can interpret these constraints. The procedure is intended to optimize the global evaluation among the communicating systems. An example from steel ...

Having in view the statistical data calculated for 10 years, the total consumption of rolling mill rolls represents 0 785...0 8 kg/tone of rolled steel. Nationwide, the 5 million tones steel being rolled every year represents a consumption of 4000 tones rolls, worth 6 million euro/year, which imposes large research with an important economic and scientific impact [1-6] It is noticeable that app...

Background: Heat stress in the steel industry is considered as a serious threat to the health and safety of workers. A wide spectrum of complications and diseases from mild disorders such as burning sensation to fatal conditions such as thermal shock may occur due to uncontrolled thermal stress. In this study, heat stress assessment was performed according to the wet-bulb globe temperature (WBG...