管線鋼規(guī)定總伸長延伸強度測量誤差及其消除方法

Measurement Error of Specified Total Elongation Strength of Linepipe-purpose Steel and Elimination Method

摘要: 對管線鋼屈服強度的檢驗,國際上普遍采用測量規(guī)定總伸長延伸強度R_t0.5的方法。分析了管線鋼在R_t0.5測量中所產(chǎn)生的誤差原因。提出了減小該測量誤差的方法,即按標準要求控制試樣加工精度;選擇合適的加載速度;采用反復(fù)校平和"預(yù)加載荷"等,克服試樣不平度的影響;試樣和引伸計正確裝卡。結(jié)果表明,采取這些方法可以準確地測量R_t0.5。

Abstract: The internationally prevailing method for testing yield strength of linepipe-purpose steel involves measuring the total elongation strength R_t0.5.The causes for the error of R_t0.5 measurement of the linepipe-purpose steel are analyzed, and accordingly, methods to mitigate the said error are proposed, including well controlling the machining accuracy of the test piece, selecting appropriate loading speed, removing the adverse effect by the unevenness of the test piece by means of repeatedly leveling and "pre-loading", and properly fixing the test piece and the extension device, etc.The application result shows that these methods are capable of accurately measuring the value of R_t0.5.