Research On Heat Transmission Of Plate In The Process Of Roller Quenching

Plate have been used in every field. In the past few years, the requirement for platehas gone up continuously both in quantity and quality. Heat treatment can not onlyimprove the handling characteristics of plate but also the mechanical properties, and theroller quenching machine is the key equipment in plate heat treating production line.Based on the rapid development of homemade roller quenching machine, the articlesimulated and analyzed both the jet impinging heat transfer of slot nozzle and thetemperature field of continuous roller quenching process by finite element method, thisdissertation consists of parts as follows:This article has studied the flow field structure and flow characteristics of the slotnozzle in plate roller quenching process, besides, the theory of heat transfer in this processalso has been researched.The slot nozzle of high-pressure quenching zone has the maximum cooling intensityin the whole plate roller quenching machine, and it plays a key role in the process of plateroller quenching. The dissertation has simulated the jet impinging heat transfer of slotnozzle by establishing a finite element model and analysed the effection of various factorsabout convective heat transfer between jet hydraulic and high temperature steel plate, suchas the velocity of jet hydraulic, jet angle, the width of slot nozzle and the temperature ofjet hydraulic.The temperature field of plate is the foundation of the whole research process aimedat plate roller quenching, this dissertation has simulated the temperature field of quenchingprocess of both high-pressure quenching method and continuous quenching method, andanalysised the advantages and disadvantages of this two quenching method by comparing.This article has received different thickness of Q690steel plates’ cooling rate which underdifferent cooling intensity by finite element simulating. This article also has calculated thekey temperature and the critical cooling rate of the Q690steel, and thus received theminimum cooling intensity in high-pressure of different thickness of Q690steel plate.Finally, the article has made sure the optimal cooling intensity in low-pressure zone by analyzing the stress difference between surface and centre of different thickness of Q690steel plate.