ANALYSIS OF ACCURACY VALUE OF NON-MANDREL DRAWN PIPE W.T.INCREASE/DECREASE DERIVED FROM RELATIVE FORMULA

The author analyzes the elements responsible for the deviation of the W.T.increase/decrease values of non-mandrel drawn pipe derived from relative formula,emphasizing that the major elements which can not be ignored are the W.T.deviation of the same length, the W.T.deviation of the same housing and the W.T.plus deviation occurring in the course of drawing with mandrel.