| 摘要 |
<p>A suspension insulator having a porcelain insulating member with a head portion and a shed, a metal cap cemented to the top of the head portion, and a metal pin cemented to the lower end of the head portion at a pin hole formed in the head portion. The pin hole has a closed top and a downward opening, and its inside surface includes a cylindrical surface portion around the opening, a curved top surface and a round corner surface forming a smooth boundary between the cylindrical surface portion and the curved top surface. The cemented part of the inside surface of the hole has sands rigidly deposited thereon over a range from its lower end to a level within +/-3 mm of the junction between the cylindrical surface portion and the round corner surface. The cylindrical surface portion has a radius equal to D and the round corner surface has a radius of curvature equal to Y, such that a ratio of Y/D is in the range of 0.3-0.45.</p> |
