Advances in the direction of reinforced connecting sleeve technology in the construction industry, the traditional connections such as lap steel, welding and other connections, either from the connection quality, efficiency or operability can not meet the needs of the rapidly growing construction industry. Reinforced connecting sleeve technology constantly updated throughout the industry led to further advances in innovation and technology. So steel connection technology in a certain sense is quite successful, and has its own characteristics, so as to adapt to industry trends and evolving society. Overlapping connection can not be used to connect large size steel, welded together with a lot of shortcomings, (unstable materials such as steel, weldability and poor conditions; unstable power situation worse welder levels; duration as well as the cold wind and rain and other climate impacts;; tight, there would not be enough capacity for high fireproof construction program sites; The quality and speed of horizontal reinforcement site connections) were unable to guarantee the quality of welding. Reinforced mechanical connection can avoid these difficulties, have shown significant advantages. The late 1980s, through the introduction of foreign advanced mechanical connection technology, coupled with the continuous efforts of a number of research institutes, experts, China's reinforced mechanical connection technology to develop rapidly. Experienced a mechanical connection sleeve cold extrusion, taper thread, upsetting straight thread until now rolling straight thread and other different stages of development, technology continues to mature and stable, the cost has also been reduced. Advantage of the new reinforced connecting sleeve in the following areas: 1, without affecting the chemical composition of steel, human factors, climate, electricity and many other factors; 2, no pollution, environmental compliance, no fire safe and reliable operation of the construction; 3, wide application, and the same applies to a variety of orientations, reducers reinforced the connection; 4, high strength, stable and reliable quality; 5, simple operation, construction speed.