Discussion on New Pipe Rolling Processes of PQF, CPS and PAM

Briefed in the paper is the history concerning inventions and operations of the seamless steel tube rolling processes,namely continuous rolling,three-roll rolling,MPM,and planetary mill,which were born Subsequent to the invention of the rotary piercing process by the Mannesmann brothers. Over the recent years,the CPS process has been experimented in South Africa;the first PQF mill has been put into operation in Tianjin,China,and the embryonic form of the planetary Assel mill(PAM) has been conceived. Also briefed are the respective features of the said three new pipe rolling processes,and a comparison of the advancement levels of the three processes as "new" techniques and evaluations thereof are made. The author forecasts a possibility of turning the PAM dream into reality some day in the future,and more sensational inventions to be made in the arena of steel tube industry.