Pipe joint, which is formed from the end portions of pipe sections to be joined together with the portions including a collar, and from flange parts which, as seen from the junction, are placed on different sides of the collars and tightened with applicable fixing members, such as with screws and nuts. The collar of the pipe section is formed from the wall of the end of the pipe section by shaping with a shaping member. The joint surface of the collar of at least one of the pipe sections to be joined is arranged to be divergent by the amount of an angle α, β from the plane perpendicular to the longitudinal axis of the pipe section. A method and to a flange part arrangement are disclosed.