1, the hydroforming corrugated tube hydroforming is the most commonly used corrugated pipe forming method. Using liquid pressure in the tube billet is the tube billet bulging in limiting ring, along the ring until the yield to appear, and then compressed pipe

to the required length. Small diameter bellows in this way. 2, rolling corrugated pipe rolling forming process is mainly used for machining large corrugated pipe, is relying on the forming of tube billet rolling wheel, can roll single-wave made into shape, some devices can also be a into a ripple. 3, mechanical bulging corrugated pipe used in the pipe internal dilation is milled, swelling pressure into corrugated individually, preliminary formed, with internal and external kun coining customization. 4, welding bellows for excessive high or waveform wavelengths, special corrugated pipe, use stamping welding process more. When the wave height more than the limit, the elongation of materials has not allowed to use the whole forming process, or because of waveform

complex, extremely difficult also will use the whole forming welding. This kind of corrugated pipe due to can't bear internal pressure, is not suitable for flexible segment of expansion joint. 5, sedimentary forming corrugated pipe the technology is using the electrodeposition method to deposit bellows materials to core mold, then the core mold corrosion. The corrugated pipe material is a kind of very soft and pure nickel metal materials, and is no

hole, therefore, can high vacuum, and welding can be performed. Use this kind of bellows expansion joint flexible segment should not be, because the cost is high, and nickel materials only.