金属收颈罐缩口成形时的缩口力与临界缩口尺寸

应用金属塑性成形理论分析金属收预罐缩口成形工艺中的缩口力和临界缩口尺寸两个主要技术参数。导出了以折屈失效作为破坏形式的临界缩四尺寸和缩口力的工程计算公式，对缩回工艺的拟定具有重要的参考价值。

The Contracting Stress and Critical Contracting Size of Metal Tin Necks at Forming

With the applied theory of metal plastic forming, two major technical parnameters in the shaping of contracting mouth of metal tinnecks --the contracting stress and the crtical contracting size are discussed. The engineering calulating formulae of the critical contracting size and strength are intnduced with the fracturing and bending efficiency loss as the destructing shape. The formulae are valuable to the drafing of contracting process.