Piercing plug for hot-rolled seamless steel pipe and processing technology thereof

The invention discloses a piercing plug for a hot-rolled seamless steel pipe and a processing technology thereof, and the piercing plug is processed by the following components by weight percent (the total weight is calculated by 100%): 0.2%-0.3% of C, 0.3%-0.5% of Si, 0.4%-0.6% of Mn, 1.0%-2.0% of Cr, 1.5%-4.0% of Ni, 2.5%-3.0% of W, 0.5%-1.5% of Mo, 2.0%-4.0% of Co, 0.05%-0.1% of Yb, and the balance of iron and inevitable trace impurities. The axial direction of a die of the plug to be poured is mutually vertical to or parallel to and in coincidence with a main shaft of a centrifuge before pouring, and the nose part of the plug faces outward or downward; and molten metal serially enters into a cavity of the die of the plug during the pouring, the rotational speed of a centrifugal casting machine is not lower than 220rpm, and the rotational speed of the centrifugal casting machine is adjusted in the range of 220-300rpm when molten steel is completely injected into the cavity of the die. The piercing plug has the advantages of uniform and compact structure, good high-temperature strength and excellent thermal fatigue performance, and the service life is 1.5-2 times of that of similar products at home and abroad.