Abstract: Elaborated in the article is a new technology to produce large-medium sized hi-alloy steel tubes,involving a mini-flow process of "centrifugal casting of hollow bloom+hollow bloom special treatment+hot rolling on pushing bench mill".Based on analysis of the mechanical properties,corrosion resistance and microstructure of the tubes from trial production,it is concluded that as a break with the intrinsic limitation of the conventional piercing process,the said new mini-flow process is suitable for producing hard deformation hi-end tubular products which possess excellent overall performance characteristics.The new process is also remarkably advantageous in energy saving and consumption-reducing(by 10% approximately).