With the development of building industry, the high-rise building, large-span space and special structures are more than before. The application of building rebar is developed towards big diameter,dense and high strength way. Now it is difficult to satisfy the need of only using traditional rebar splicing technology such as jointing & colligation, electrical arc welding, flare welding, air pressure welding etc. In 1987, Chian Academy of Building and Research began to research the rebar mechnical splicing technology which has been developed and used. The coupler cold forged technology, tapered thread splicing technology and parallel thread splicing technology have been used earlier and later. The parallel thread splicing technology can be divided into upsetting end and rolling end ways. During these 10 years, the rebar splicing technology has been applied quickly. At present, the parallel rebar splicing technology has been listed as one of ten national important spreading items.

The characteristics of rebar splicing technology:

1.High strength, safe, reasonable splice pressure

2.Stalbe quality: the splice producing, setting and inspecting are all belong to machnical scope, which quality is easy to control and will not affected by rebar rib, carbon quantity and welding character etc.

3.Good economic efficiency: no rebar overlaped splicing, steel-saving

4.Widen applied field of splice: adaptable for Φ12-Φ50 same diameter,different diameter,bending, new and old, advance cover up rebar of GB 14599 or BS 4449(CS2) standard

5.Fast splicing speed: splicing effect is good, sturcture is tight, good for concrete construction

6.Good for environment-protection: no light-fire work, no environment pollution. Can work the whole day and can realize polite and industrialized producing