Subsea Riser Products (SRP) has successfully attached the first flanges to pipe sections that will make up a unique ultra-high-pressure drilling riser for use by Venture Production in the North Sea. The flanges were joined to the pipes at SRP's premises in Sheffield, UK, using a novel shrink-fit process that the company developed specifically with the fabrication of risers like this one in mind.

SRP managing director Simon Luffrum said, "The development of the shrink-fit flange has been the key to this entire project. We have had a good deal of interest in the technique from a number of other operators. Now that we have proved the technique it is likely to find application in a variety of riser-related projects in the future."

The flange is first heated using induction coils to over 400 degrees C, which causes it to expand sufficiently to fit over the end of the 19 1/4-in ID riser pipe section. The flange and the pipe are then carefully brought together -- this part of the process takes no more than 30 seconds -- using a purpose-built jig to ensure the precise alignment of the two parts. Simply allowing the assembly to cool down creates a high-quality structural connection and a gas-tight seal.

Tags: Subsea Riser Products, Venture Production plc