UNION SCREW FOR A PIPELINE PROVIDED WITH AT LEAST ONE FLANGE, IN PARTICULAR A BRAKE PIPE

A union screw () for pipes () provided with at least one flare () comprises a metal base body () which accommodates the pipe (). The union screw () further comprises a screw head (), a threaded portion (), a contact portion () which is configured to abut the flare () of the pipe (), and a functional layer () with which the base body () is coated at least in the region of the threaded portion () and the contact portion (). The functional layer () is multi-layered and consists of at least one base coat () and a top coat () applied to the base coat () at least in some areas. The base coat () forms a structure for creating corrosion protection and a far-reaching invariance with regard to the material of the usual friction partners of the union screw () which, in addition to a binder, also contains zinc in the form of zinc-containing lamellae (), which are oriented to lie substantially flat on the base body ().