1. Tablet welded titanium pipe: Compared with the multi-slit "shrimp" type, the titanium pipe has fewer welds, but the more complicated the tabletting process, the more molds are needed, the more materials and processes are consumed, and the more welds are required. Corrosion resistance is also affected and appearance is not ideal.

2. Multi-weld type (commonly known as "shrimp waist" type) titanium tube: its processing technology is complicated. Usually, the tube is cut into multi-section oblique openings, welded or formed into multi-section unfolded materials under the plate, and then rolled and welded. This method has more leftover material and a large amount of welds. Because the welding seam will greatly reduce the corrosion resistance, it is easy to leak, and the appearance is not good. The inner surface is a folded surface, which increases the transmission resistance of the pipeline and increases the erosion corrosion of the back and reduces the service life.

3. Stamping titanium welded pipe: The appearance of this titanium pipe does not seem to be different from the push-made titanium pipe, but the processing process is to stamp the tube blank in the punching die on the punching song. During the forming process, the back of the titanium pipe is pulled and forced. The back is thinned, the inner tube wall is thickened under pressure, resulting in uneven wall thickness or wrinkling, and the back of the titanium tube is subject to erosion and corrosion during use. Because the back wall is thin and prone to premature damage, the overall life of the tube is greatly reduced.

4. Cast titanium tube: Although it is a seamless titanium tube, the wall thickness (at least 5mm) and the pipe wall thickness (2mm~4mm) cannot match, thereby increasing the transmission resistance, and the surface finish is poor. More importantly, there are internal A large number of defects such as pores caused by manufacturing seriously affect the corrosion resistance and service life. The above several kinds of titanium tubes are far from meeting the current requirements, and the advent of push-made titanium tubes is quickly accepted and welcomed by users because push-made titanium tubes have their own characteristics. The processing of the titanium welded pipe uses the seamless titanium pipe as the billet, and the billet with the pipe diameter smaller than the finished product diameter is used to push and extrude on the special push extrusion machine. During the forming process, the pipe billet expands. Stress analysis shows that the stress in different parts is different, but under bidirectional compression, namely axial compression, radial compression and circumferential tension, the stress is always in tension.