公开(公告)号：US20210199224A1

公开(公告)日：2021-07-01

申请号：US17055259

申请日：2019-07-03

Applicant: ABB Power Grids Switzerland AG

Inventor： Anders C. Johansson ,  Magnus U. Henriksson ,  Anders Holmberg

IPC: F16L47/16 ,  B29C70/30 ,  B29C70/54 ,  B29C53/56 ,  F16L9/12

Abstract: The present disclosure relates to a fibre reinforced polymer (FRP) tube, the tube comprising a plurality of concentric layers of an FRP material forming a shell of the tube. At least one blind threaded longitudinal bolt hole is provided from a transverse end surface of the shell. The bolt hole extends in at least three of the plurality of layers, a middle layer encompassing a plane passing through a center of the bolt hole, an inner layer encompassing a plane of an innermost extent of the bolt hole, and an outer layer encompassing a plane of an outermost extent of the bolt hole. The fibre filament of each of the inner and outer layers has been wound at a first angle to the longitudinal axis and the fibre filament of the middle layer has been wound at a second angle to the longitudinal axis.