When ordering other than standard Butt Welding end valves, specify schedule of pipe end and give complete data concerning style, figure number and contour of weld end.
如果订购其它标准的对焊连接的阀门，请告知管道管壁厚度标准，以及种类、型号和焊接端轮廓等参数。
2
Through the comparative analysis between ordinary facial feature vector and the standard value of perfect human face, the main factor of the imperfect face is imperfect facial contour.