US Patent 10359029 Connection piece for a pitch tube

A connection piece for a pitch tube of a wind turbine in which the connection piece comprises a receiving portion into which the pitch tube is at least partially insertable. The connection piece is made from at least first and second parts. The first part comprises a first, at least partially annular sealing surface and the second part comprises a second, at least partially annular sealing surface. The first sealing surface and the second sealing surface, together with part of the surface of the pitch tube, form at least part of a surface that delimits a hollow space for receiving a seal, when the pitch tube is inserted into the receiving portion. At least one element varies the spacing distance between the first sealing surface and the second sealing surface.