Abstract: A means of connecting pipes, comprising a seal (2), flanges (3, 3?), a threaded portion (15) and a nut (5), where the end portion (1, 1?) of the pipe is equipped with a concentric press surface (23) located immediately proximal to the periphery of the pipe (1, 1?) and designed to be able to take an axial pressure from a preloading tool (25), which pressure is distributed evenly or point-by-point about the periphery of the pipe. A means of compressing pipe couplings, where a preloading tool (25) comprises two end sections (27, 31) connected to two or more rods (35), each rod (35) being equipped with a hydraulic cylinder (37).