Secretary general of the China general machinery valve industry association Song Yinli to visit our company. In strengthening and always accompanied by zhu visited the workshop, and introduces the stem invention of cold extrusion technology and stem the surface of the polished rod to mirror effect, and the technique not only increased the stem polished rod surface hardness but also greatly improves the sealing performance of the valve, the technology to fill the domestic blank has reached the international advanced level. Song secretary general of the invention patent product gave high evaluation, and I hope we continue to put into scientific research, zhiyuan valve brand to do strongly does.