Abstract: A flange compression pipe coupling wherein the end portions of the pipes to be coupled are surrounded by an inner jacket consisting of ductile metallic material. The inner jacket is surrounded by a radially deformable outer jacket which is biased against the exterior of the outer jacket by two flanged rings having conical internal surfaces. The outer jacket causes plastic deformation of the inner jacket until the latter sealingly engages the end portions of the pipes whereupon the extent of plastic deformation of the inner jacket remains unchanged.