摘要
ＡＰＩ圆螺纹的锥度和中径是两个重要的参数。从理论分析知， 锥度公差和中径公差是相互影响和相互制约的， 目前ＡＰＩＳＴＤ５Ｂ标准中对二者的公差规定未能显示出这种相关性， 因此出现中径公差合格而锥度公差却可能不合格， 以及锥度公差合格而中径公差却超出范围的情况， 这对螺纹公差控制及套管的使用性能带来不良影响。建议将锥度公差和中径公差的控制有效地结合起来， 即变为仅控制中径公差； 也可先确定锥度公差， 然后反推出中径公差的大小， 与紧密距折算的中径公差相比， 精度明显提高。
The taper and pitch diameter of API round thread casing are two of the most important parameters. It is known from theoretical analysis that taper and pitch diameter are not isolated but have close relationship, while this relationship isn't described in the stipulation of tolerance in API STD 5B. Therefore it is often found that the taper is eligible, but the pitch diameter is ineligible; or the pitch diameter eligible and the taper ineligible when the casing thread is measured. This has bad influence on the control of thread tolerance and the performance of the casing. It is suggested that the control of the two tolerances be combined, and the pitch diameter tolerance be controlled only.
出处
《石油机械》
北大核心
1999年第6期15-17,共3页
China Petroleum Machinery
关键词
API
圆螺纹
锥度
中径
公差控制
API round thread taper pitch diameter tolerance control
