Helical Coil Gets a U-Neek Bend

Helical Coil Gets a U-Neek Bend

Fabricating equipment for the chemical sector requires solid high quality materials and superior workmanship. In April 2011, ASSDA member and Accredited Fabricator U-Neek Bending Co Pty Ltd put the finishing touches on a radiant helical coil at their factory in Dandenong, Victoria.

The coil, designed as a heater for Titanium Tetrachloride (TiCl4) production, is 11.4 metres long with a diameter of 3.05 metres and required more than 7 tonnes of high grade Inconel Alloy.

U-Neek’s Business Development Manager, John Lovell, said the client chose to have this material shipped from America.
“At around US$1000 a metre, Inconel Alloy is a very expensive option but it has great heat transfer properties and is completely non-corrosive,” Mr Lovell said.

The Western Australian client, who declined to be named, were looking for a fabricator that, in addition to having a proven record in metal bending, could work to their particular requirements for this critical process componet.

“U-Neek weren’t just competitive in pricing,” said Greg, a project engineer with the client. “They succeeded with all the trial projects we sent them.”

“To ensure total quality control, we provided a comprehensive report that detailed every step of the process, including the names of every person who worked on the individual stages,” Mr Lovell said.

U-Neek Engineer Dale Theobold said the coil was manufactured to exacting tolerances using a range of Inconel Alloy materials.
“We used 150NB Schedule 40 seamless 600 for the pipes and flanges, 366-04 WPNCI-S for the elbows, B168-08 for the plate and 253MA for the high temperature pieces,” he said.

Once completed, the coil then had to undergo a rigorous series of tests. The butt welds were verified with full radiography, the attachment welds were submitted to liquid penetrant inspection (LPI), and a full hydro exam was done on the coil itself.

“The coil was filled with distilled water to test its heating capabilities. Then the coil was pressurised with nitrogen, to a dew point of -12°, to remove all traces of water and moisture prior to transporting,” Mr Lovell said.

The transport frame and mounting jigs were manufactured from mild steel. To ensure no cross contamination, Inconel strips were fitted to the mounting points. The coil was lifted onto the back of a semi-trailer for final transportation to Perth, using U-Neek’s 16 tonne travelling overhead cranes.

Images courtesy of U-Neek Bending Co Pty Ltd.

This article features in Australian Stainless magazine - Issue 50, Summer 2011/12.