DYHI has set up a quality department to track and inspect the product quality, and has full-time inspectors. All inspectors have been trained by national professional training institutions. The inspectors not only have chemical and mechanical inspection qualifications, but also have magnetic particle, penetration, ultrasonic and radiographic nondestructive inspection qualifications. It can provide various physical and chemical performance test data from raw materials entering the factory to finished products leaving the factory, so as to ensure that the products are 100% qualified. Moreover, all inspection data files are important evidence of inspection work. Therefore, our company has also Set up a separate inspection data file room and equipped with full-time documenters to collect, archive, manage and retain inspection data etc.

DYHI establishes and implements the "three inspection" system (self inspection, mutual inspection and handover inspection); The product quality management shall strictly comply with the requirements of iso9001-2015 quality management system. In the processing process, the operators and quality inspectors shall carefully implement the three inspection systems of "mandatory inspection for each piece", "patrol inspection" and "final inspection and acceptance", and require the processors to implement the three controls of "self inspection, mutual inspection and special inspection", so as to effectively control each link, quality post and quality control point in the production process, Strictly ensure the qualified rate of products.