Liyuan window profiles, Ltd. Weifang development from design to production of doors and windows, all in accordance with international quality management system certification, and through strict internal management system for each production processes are strictly monitored to achieve a comprehensive and quality control of the production process, developed a strict perfect production management standards, the use of the computer program control, every aspect of the production, testing, packaging, storage, installation and other closely monitored, meticulous, never allow an illegal factory, to ensure that products from the fundamental production quality to ensure the interests of users, so that Liyuan doors more and more users of all ages and affirmation.