This article takes the flange nut as an example,discusses the technique of cold extruding seamless pipe to make large flange nut and the feasibility of the technique.

A new seamless integrated navigation algorithm was proposed on the basis of ANFIS in order to enhance the performance of GPS/INS integrated navigation system during GPS outages.

In order to strengthen the oil-field user’s confidence in the ERW casing made in China,the contrast study of the dimension control,residual stress,and pipe collapse pressure between ERW and seamless casing was conducted in this paper.

Present Status and Development of Alloy Steel Seamless Tube;

Analysis on stretch reducing rolling process of seamless tube by FEM;

Based on the deformation characteristics of seamless tube during stretch reduction,a 3-D thermo-mechanical coupled finite element model was established to simulate the deformation process of tube on 18-stand stretch reducing mill.

Technological transformation of enterprises produced medium diameter seamless steel tube with cold drawn processing;

Discussion on development countermeasures to seamless steel tube technical equipment in China;

Present situation analysis of Chinese seamless steel tube technology equipment;

Discussion on the developing direction of steel tubes by comparing processing of seamless tube and welded tube;

China steel tube trade is being a turning point, concerning which should take the first place between seamless tube and welded tube.

This paper describes the deformational characteristic of different kinds of cross-rolling process, sumerizes the law of development cross- rolling elongation and reveals the tendency of hot elongated accurate seamless tube.