由于塔干罗格冶金厂取消了4～6″周期轧管机组的水压穿孔机,用延伸机代替穿孔机穿孔,所以对钢锭(包括冒口用复合保温材料浇铸的钢锭)穿孔工具的孔型设计还需进一步研究探讨。延伸机改用直径345～365mm圆锭取代直径375～395mm的23角锭和圆锭轧管时,最初,延伸机仍采用轧制杯形坯的工具孔型 As the Taqqaraoguo Metallurgical Plant canceled the 4 ~ 6 "cycle of the pipe mill perforation machine, with the extension machine instead of punching machine perforation, so the ingot (including the riser with a composite insulation material casting ingot) perforation tool hole Type of design needs further study to explore extension machine to use a diameter of 345 ~ 365mm ingot instead of diameter of 375 ~ 395mm 23 angle ingot and round tube, initially, the extension of the machine is still using the cup-shaped tool hole rolling pass