关键词: 钻铤用4145H钢, Φ600 mm圆坯, 热送热装, 温送温装, 冷送冷装

Abstract: Taking 4145H hot-rolled round steel used for oil drill collars as the research object， under the condition of high temperature （870-920 ℃） in the preheating section of the heating furnace， a warm delivery and charging process is designed： the surface temperature of the casting billet is controlled at 200-400 ℃ before being put into the furnace， the preheating section time is ≥ 120 min， the temperature of the heating section is 950-1 050 ℃， the holding time is ≥ 60 min， the high temperature section is 1 220-1 280 ℃， the holding time is ≥ 240 min， and the total heating time is ≥ 510 min. Through process test， Φ260 mm specification round steel bar is rolled by using Φ600 mm specification continuous casting round billet. By comparing the quality of hot rolled round steel under three furnace charging modes of hot delivery and hot charging ， warm delivery and warm charging， and cold delivery and cold charging， it is concluded that the warm delivery and warm charging process can obtain good surface quality and internal quality.

Key words: 4145H Steel for Oil Drill Collar, Φ600 mm Round Billet, Hot Delivery and Hot Charging, Warm Delivery and Warm charging, Cold Delivery and Cold Charging