Chinese President Xi Jinping on Monday visited Yangquan Valve Co., Ltd. in north China's Shanxi Province. President Xi inspected the production workshop, learned about operations and sales, and had a cordial conversation with workers. Founded in 1924, the century-old enterprise has become a technologically advanced "little giant" and a national high-tech enterprise. By strengthening its technological research and development and pursuing independent innovation, the enterprise has obtained a series of patents.