波纹管是轴对称的表面上具有同心环状波纹的薄壁壳作(见图18)。波纹管的种类很多,按材料分有金属(铜合金、不锈钢等)和非金属(聚四氟乙烯等合成树脂等)两大类。金属波纹管按毛坯及制造工艺可分为两类:①用无缝薄壁管经机械或液压方法成形的;②用膜片组合焊接制成的。目前,在气动技术中一般以采用无缝薄壁金属管成形的波纹管居多。在特殊要求的场合,为了提高耐压力、增加柔软性,也可采用将二、三 Bellows are thin-walled shells with concentric annular corrugations on an axisymmetric surface (see Figure 18). There are many types of bellows, according to the material divided into metal (copper alloy, stainless steel, etc.) and non-metallic (polytetrafluoroethylene and other synthetic resins, etc.) two categories. Metal bellows by rough and manufacturing process can be divided into two categories: ① seamless thin-walled tube by mechanical or hydraulic method of forming; ② welded with a combination of diaphragm. Currently, pneumatic technology is generally used in the formation of seamless thin-walled metal tube bellows majority. In special occasions, in order to improve pressure resistance, increase flexibility, can also be used to two or three