交联聚乙烯与硅橡胶界面涂抹不同硅脂对其电荷特性的影响

Effect of Different Coating Silicone Grease on Space Charge Characteristics at XLPE / SR Interface

实际电缆附件安装时一般会在附件主绝缘与电缆绝缘界面均匀涂覆硅脂,但不同种类的硅脂对界面特性的影响尚未见报道。为此,选用2种常用工业硅脂(普通硅脂(CSG)和氟化硅脂(FSG)),采用电声脉冲法(PEA)测试不同硅脂涂层对交联聚乙烯/硅橡胶(XLPE/SR)界面电荷特性的影响;并通过机械拉伸实验验证硅脂对硅橡胶材料的溶胀效应。结果表明:氟化硅脂具有较强的电负性,使得试样界面更易于积聚电荷;普通硅脂和氟化硅脂对硅橡胶都具有溶胀作用,进而导致XLPE/SR夹层界面正电荷向硅橡胶体内迁移;老化后,涂覆普通硅脂的硅橡胶力学性能的下降程度更为明显。

In the installation of cable accessory, the interface between cable accessory insulation and cable insulation is usually coated evenly by silicone grease. However, the effect of different kinds of silicone greases on interface characte- ristics is barely reported. Therefore, using two common kinds of silicone greases in industrial applications, namely, the common silicone grease （CSG） and the fluorinated^silicone grease （FSG）, we researched the effect of silicone grease coating on the space charge characteristics of the interface between cross-linked polyethylene （XLPE） and silicone rubber （SR）, which was measured by using the pulsed electroacoustic method （PEA）. The swelling effect of silicone grease on SR was also investigated through mechanical tensile experiments. The tests show that, compared with CSG the FSG coated interface of XLPE/SR is easier to have charge accumulated for its stronger electronegativity. Both CSG and FSG have swelling effect on SR, which will make the positive interface charge transfer inwardly into SR; meanwhile after ag ing, the CSG coated SR shows a more dramatic decline in mechanical property.