| Crane is an important hoisting equipment which is widely used in the engineering construction and plays an essential role in the building of national infrastructure. With the deep going of the Reforming and Opening policy of our country and quick development of national economy, the national infrastructure contracture is booming and market demand of engineering machine in increasing quickly. Now Cranes of the order of 100 tons are all depending on importing in domestic market. Some foreign crane corporation companies are intended to gain more share of our domestic crane market. In order to seize this market quickly and develop domestic market, developing all ground based QAY125 crane is decided by our company. All ground based QAY125 crane product independently researched and developed by Xuzhou Heavy-duty Machine Co., Ltd is investigated and the whole process of its design, calculation, prototype development, experiment and authenticating is described in this paper. Advanced foreign technology is incorporated in this product and integrated computer control, full automatic single-cylinder bolt styled telescopic arm, elliptic hanging arm and oil gas hanging, all wheel steering and multiaxle driving, etc key technologies is conquered in its design and manufacturing process. By using five axles chassis, all wheel steering and cancroid running can be realized in the vehicle with the advantage of wider branch leg span and better working stability. The research includes: (1) Determining the whole plan of all ground-based QAY125 crane, specifying this product's market orientation, design ideology, main technical characteristic, performance, main kit and whole layout and structure requirement. This plan is close to the international advanced technology. (2) By designing, manufacturing, testing and improving, full automatic single-cylinder bolt styled telescopic arm and oil gas hanging technologies are mastered and used in the product as key factor of the successful developing all ground-based QAY125 crane. (3) Via the overall calculation of all ground-based QAY125 crane, integral matching, mechanism calculation, structure strength calculation and complete machine stability calculation are carried out and lifting performance and performance parameter are determined. (4) Prototype development of all ground-based QAY125 crane is organized. Hanging arm molding and welding technique is researched. Problems emerging in the manufacturing process are handled in time and design is improved. (5) Through the factory testing, mode testing, strength testing and overall testing of this all ground-based QAY125 crane, national environmental protection and related standards are reached and design requirements are satisfied. Mode testing of the National Engineering Machine Supervisory and Surveying Center and the compulsive program detection of the National Automobile Quality Supervisory and Surveying Center show that all indexes of the whole machine reached the requirements of task design book and related standards. Besides, national compulsive standards about safety and environment protection are reached. Experts from the Jiangsu Science and Technology Office conclude that the technology of the whole vehicle has reached the advanced level of similar international products. Through the thorough research of all ground based QAY125 crane product, achievement, experience and knowledge property rights are owned by our company, the situation of crane of the order of over 100 tons depending on importing is changed, and it also lay a basis for the further development of domestic all ground based crane products. Now, key technologies are applied in a series of products and several national patents are gained. |
