Method of connecting tubular members in offshore structures

A method of connecting tubular members, each tubular member having a radially outward projecting flange at its end for connecting the tubular members end-to-end, the method comprising:

• positioning two of the tubular members end-to-end with their flanges aligned and abutting each other, thereby forming adjacent flanges;
• providing a plurality of clamp units and securing the adjacent flanges to each other by positioning the clamp units on various predetermined segments of the adjacent flanges;
• wherein each clamp unit has a base comprising a first portion from which jaws extend to form a receptacle therebetween for receiving and containing one of the predetermined segments, wherein a width (W) across the receptacle between the jaws is too small for the receptacle to receive the predetermined segment of the adjacent flanges when the first portion of the base is at ambient temperature;
• for receiving the predetermined segment of the adjacent flanges in the receptacle, heating the first portion of the base and by expansion of the first portion increasing the width (W) and positioning the clamp unit with the predetermined segment of the adjacent flanges in the receptacle while the width (W) is increased;
• then, decreasing the width (W) and pressing the adjacent flanges together due to contraction of the jaws;
• wherein the increasing of the width (W) is achieved by thermal expansion of the first portion during the heating of the first portion, and wherein the decreasing of the width (W) is achieved by reducing a temperature of the first portion to ambient temperature and by a corresponding thermal contraction of the first portion.