Research Of Key Technology In Spraying Borax System For Seamless Steel Pipe

The iron oxide scale which produced in the hot rolling seamless pipe have a serious impact on the pipe qualified rate. Spraying borax system is a kind of device,used for removing iron oxide scale. It’s working principle is blowing nitrogen gas to the pipe inner wall with borax particles, at high temperatures, borax and iron oxide scale will produce chemical reaction,and then the oxidation iron sheet off, the steel pipe filled with nitrogen.In this Situation,the gas nitrogen prevent the oxygen further exposure to the steel pipe. In order to optimize the effect of removing iron oxide scale,this thesis sets of equipment as the research object, innovation and improvement the key technology of the exist equipment, so as to further enhance the rate of finished products of seamless tube.The working principle of spraying borax system were summarized in this paper. With the current situation of this foreign equipment,we solved many key technology problems.Such as:the borax injection quantity control, the service life of the sealing elements, antioxidative materials supply mode, position changeover valve angle, the equipment running status monitoring and assembly level.Blowing is one of unit of the antioxidant system,and the nozzle is a part of the blowing unit.It directly influences the blowing effect of the system. This paper based on the past experience value,made some new improved design on the nozzle.Set up five kinds of physical model. Combined with the key technology parameters of the system, determined the reasonable initial conditions and boundary conditions, use CFD simulated the internal flow field of the nozzle, make sure whether borax produce cyclonewhen it sprayed out through nozzle, so as to verify whether the design is reasonable.The paper has also established and simulated the model with different vane angles. Got the optimum vane angle range by comparing the nozzle outlet velocity vectors. Based on the optimum vane angle range, identified maximum and minimum values of the nozzle outlet diffusion angle, according to the system pressure range.and thus get the corresponding pipe diameter range.Finally according to the WinCC interface data, verified the feasibility of new nozzle by comparing the consumption amount of borax.This thesis optimized for the enterprise improve spraying borax system offers the theoretical basis.This paper is commissioned project by enterprise.It provides reference for the enterprise to optimize and improve spraying borax system which through simulation and analysis of the nozzle.