电泵井套管杂散电流现场测试

Field test of stray current in electric pump oil wells

现场测试了萨北油田北部过渡带区域电泵井套管附近的杂散电流.测试结果表明:该区域电泵井套管存在交流杂散电流腐蚀.通过现场布点测试发现该区域土壤具有较强的腐蚀性,高压线附近存在强杂散电流,电位梯度为1.30～15.00mV/m;地下50m处有中等强度杂散电流,电位梯度为2.34～2.60mV/m;地下100m处有弱杂散电流存在.虽然杂散电流并不连续,但可加剧土壤电化学腐蚀.

Through scanning the pitted leak casing in the electron microscope, we find that the galvanic corrosion and the electro-chemical corrosion lead to the casing leak in electric pump oil wells in the transition terrain region north of Sabei oil field. Through testing on the spot, we find the soil has the stronger corrosive effect. There is a big stray current under the high voltage wires with a electric potential gradient of 1.3～1.5mV/m. There is a medium intense stray current underground 50m deep with a electric potential gradient of 2.34 to 2.60 mV/m. The galvanic corrosion speeds up the process of the electro-chemical corrosion. So the casing of the electric pump oil wells must be protected in the region.