为了进一步分析SEW J55 LC套管螺纹连接质量的影响因素以及套管发生异常脱扣失效的原因,以Φ139.7 mm×7.72 mm SEW J55 LC套管为例,从套管使用工况、螺纹加工参数、拧接扭矩控制等方面进行了试验研究。结果显示,SEW套管在弯曲状态...为了进一步分析SEW J55 LC套管螺纹连接质量的影响因素以及套管发生异常脱扣失效的原因,以Φ139.7 mm×7.72 mm SEW J55 LC套管为例,从套管使用工况、螺纹加工参数、拧接扭矩控制等方面进行了试验研究。结果显示,SEW套管在弯曲状态拉脱试验、螺纹参数极限匹配下拉脱试验的拉脱载荷均高于API TR 5C3标准要求。研究表明,按照内控标准生产加工的SEW套管满足标准要求,弯曲工况、螺纹加工工艺、存放时间和J值均不是套管异常脱扣失效的原因。为提升SEW J55 LC套管螺纹连接质量,预防套管在油田使用中出现异常反拧退扣,建议将拧接扭矩在推荐标准基础上增大10%执行。展开更多
In order to explore a breeding method for mycoplasmal pneumonia-negative swine population, the purifying effects of combination therapy, SEW and three-point breeding and management system on Mycoplasma hyopneumoniae w...In order to explore a breeding method for mycoplasmal pneumonia-negative swine population, the purifying effects of combination therapy, SEW and three-point breeding and management system on Mycoplasma hyopneumoniae were investigated in this study. After the processes of screening pregnant sows, programmed therapy for sows, SEW, three-point breeding and management in the barrier isolation system and programmed therapy for piglets, the newly-bred piglets were monitored as long as four months by serum antibody detection of Mycoplasma hyopneumoniae and fluorescent quantitative PCR of nose swabs. The results showed that when the newlybred five batches of piglets were older than 35 d, they were all negative by serum antibody detection and nose swab antigen detection. Therefore, the combination therapy, SEW and three-point production and management system can effectively purify Mycoplasma hyopneumoniae, providing theoretical basis and clinical experience for the control and purification of domestic mycoplasmal pneumonia.展开更多
基金Supported by Jiangsu Agricultural Science and Technology Innovation Fund[CX(12)1001-05]~~
文摘In order to explore a breeding method for mycoplasmal pneumonia-negative swine population, the purifying effects of combination therapy, SEW and three-point breeding and management system on Mycoplasma hyopneumoniae were investigated in this study. After the processes of screening pregnant sows, programmed therapy for sows, SEW, three-point breeding and management in the barrier isolation system and programmed therapy for piglets, the newly-bred piglets were monitored as long as four months by serum antibody detection of Mycoplasma hyopneumoniae and fluorescent quantitative PCR of nose swabs. The results showed that when the newlybred five batches of piglets were older than 35 d, they were all negative by serum antibody detection and nose swab antigen detection. Therefore, the combination therapy, SEW and three-point production and management system can effectively purify Mycoplasma hyopneumoniae, providing theoretical basis and clinical experience for the control and purification of domestic mycoplasmal pneumonia.
