Abstract: The temperature change of 325 mm X 280 mm casting bloom of bearing steel GCr15 during process including casting, holding conveying, stacking cooling and heating in heating furnace has been studied by using numerical simulation method and temperature-measuring in situ. Results show that with bloom out of withdrawal and straightening device during conveying process by single roller way, the difference of cooling rate at different parts of casting bloom is larger i. e. the cooling rate at comer 10 ℃/min, surface 7.1 ℃/min and core of bloom 4.6 ℃/min, while the difference of cooling rate at different parts of casting bloom is smaller during conveying process with holding pot ( comer 4 °C /min, surface 2.9 ℃/min and core 1.67 ℃/min) and during stacking cooling period, therefore to shorten the remaining time at tail of caster is available to avoid tiny cracks caused by uneven cooling. As compared by cold charging, the heating time of bloom shall be decreased by 20 min by hot charging process.

Key words: 325 mm x280 mm Casting Bloom, Bearing Steel GCr15, Temperature, Holding Conveying, Stacking Cooling, Heating, Numerical Simulation, Measuring in Situ

摘要： 通过数值模拟和现场实测的方法研究了在连铸、保温输送、堆垛冷却、加热炉加热等工艺过程中325 mm ×280 mm GCr15轴承钢连铸坯温度的变化。结果表明,铸坯在出拉矫机后的单辊道输送过程不同部位的冷却速率差异较大(角部10℃/min、表面7.1℃/min、芯部4.6℃/min),而在保温车输送过程(角部4℃/min、表面2.9℃/min、芯部1.67℃/min)及堆垛冷却期间不同部位的冷却速率差异较小,因此缩短在连铸机尾部的停留时间有利于防止因冷却不均产生微小裂纹。热送热装较冷装工艺可使铸坯的加热时间减少20 min。

关键词: 325 mm x 280 mm铸坯, GCr15轴承钢, 温度, 保温输送, 堆冷, 加热, 数值模拟, 现场实测