Patent classifications
B
B21
B21B
19/00
B21B19/02
B21B19/06
B21B19/08
B21B19/08
SKEW ROLLING APPARATUS, METHOD FOR MANUFACTURING SEAMLESS PIPE SHELL, AND METHOD FOR MANUFACTURING SEAMLESS STEEL PIPE
A skew rolling apparatus with which shape defects in non-steady-state portions at the front and back ends of a seamless pipe shell can be prevented. The skew rolling apparatus includes a skew pierce rolling mill configured to pierce roll a steel material into a seamless pipe shell, and a skew outside-diameter mill following the skew piercing mill in a pass direction of the seamless pipe shell in the skew rolling apparatus. The skew rolling apparatus satisfies specified formulae.