| 摘要 |
The invention relates to a drill string element including at least one refill layer. Said layer includes one or more cords of filler metal, each cord having a width between 1 and 5 millimeters and being laid adjacent to each other so as to form a substantially continuous layer over one area of the element. The hardness in the body of the layer varies by less than 10 HRC over said area. |
