高温高压对井下套管强度影响研究

EFFECT OF HIGH-TEMPERATURE AND HIGH-PRESSURE ON DOWNHOLE CASING STRENGTH

李文魁 薛延平 李鹤林 金志浩 高惠临

Li Wenkui Xue Yanping Li Helin Jin Zhihao Gao Huilin

西安交通大学材料学院, 陕西西安 710049 中国石化集团公司, 北京 100045 西安石油大学电子工程学院, 陕西西安 710065 石油管材研究所, 陕西西安 710065

为了确定材料强度与温度、压力的关系式,建立了热内能表达式。理论分析与实验表明材料的熔点温度tm是压力p的函数,材料所处的压力越高,相应熔点温度也越高,静水压力是通过对材料熔点的影响而影响材料的强度。在同样的温度条件下,如果熔点升高,则材料强度也将提高。高压或超高压下,材料强度将等于或高于理论强度,表明金属中的缺陷此时已闭合。文中推导出的公式为井下套管的保护及防治提供了理论依据。

In order to determine the relational expression of temperature, pressure and material intensity, the expression of is established in this paper. Theory analysis and the experiments showed that the melting point temperature of material is the function of pressure p. Higher the pressure of the material is, higher the melting point temperature. Hydrostatic pressure affects the material strength by affecting the melting point temperature of the materials. Under the same temperature, if the melting point is improved the material intensity will be improved. On the condition of high pressure or super-high pressure, material intensity will be equal or over its theory value, which shows that those defects existing in metals have closed at that time. The formula deduced in this paper provides the theoretical foundation for the downhole casing protection and prevention.

10.3969/j.issn.1000-7393.2005.03.006