基于数字射线的耐张线夹压接质量评价试验

Quality Assessment Test of Strain Camp Based on Digital Radiography

因压接质量问题导致的耐张线夹失效事故时有发生,随着线夹内部压接缺陷无损检测技术及装备的不断涌现,其检测能力验证和质量评价标准等成为亟待解决的问题。系统开展了耐张线夹压接质量的数字射线检测和评价试验,设计了钢锚和铝管压接部位凹槽欠压、钢芯和钢管压接部位未压接、铝管和导线压接部位未压接、钢管弯曲、铝管弯曲和未保压压接共6类典型缺陷,分别进行数字射线检测和握力试验。结果表明:数字射线检测技术可以直观检出除未保压压接以外的所有设计缺陷。综合握力试验和数值射线检测结果,为构建耐张线夹压接质量射线检测标准提供参考依据:凹槽欠压数量不超过2个;钢芯和钢管未压接长度小于60%;铝管和导线未压接长度小于60%;钢管和铝管弯曲度不超过2%。

The strain clamp failure occurred frequently due to bonding quality. With the continuous emergence of non-destructive testing technology and equipment for internal compression bonding of clamp, its testing capability verification and quality evaluation standards are immediate concerns. In this paper, the digital radiography detection and evaluation of the pressure connection quality of the strain clamp is carried out. Six typical defects including pressure lack of steel anchor and aluminum crimp groove, non-crimping of steel core and steel pipe crimping parts, non-crimping of aluminum tube and wire crimping parts, steel tube bending, aluminum tube bending and unpressurized clamping are designed for digital radiography detection and grip strength test. The result shows that the digital radiography detection technology can directly detect all the designed defects except the unpressurized clamping. The grip strength test and digital radiography detection results provide reference basis for strain clamp crimping quality assessment standard： the number of un-pressed groove number should not be more than 2; the length of the steel core and the steel tube without crimping should be less than 60%; the length of aluminum wire without crimping should be less than 60%; the bending of steel tube and alumina tube should not exceed 2%.