October,  2006:

The latest high performance compact connection technology from Vector International is set to provide significant savings and overcome potential installation and maintenance issues for a New Zealand refinery in a second furnace upgrade, to be commissioned during the March 2007 C Block shutdown.

Some 24 pairs of three inch SPO Compact Flanges are being used at the New Zealand Refining Company (NZRC) in the re-tubing of the furnace convection bank and replacement of the outlet transfer lines to the radiant bank (all being upgraded from carbon steel to stainless steel).  These compact flanges will ensure joint integrity at design pressures of 26 bar and design temperatures to 400°C – well within the capabilities of the flange which can accommodate pressures in excess of 40,000 psi and temperatures to 720°C.

Vector’s SPO Compact Flanges have been selected for the project following the success and benefits derived by NZRC in using these connections on a previous furnace radiant bank re-tube project, involving the reconfiguration and installation of a radiant coil bank and outlet transfer lines to the column.

A number of key features drove the selection of SPO Compact Flanges for both applications: ease of installation, their significantly reduced weight, and their leak-free performance and minimised maintenance requirements.

The use of SPO Compact Flanges as opposed to traditional ANSI flanges for the 24 outlet and inlet nozzles to the furnace will minimise installation issues, including avoiding the need for field welding, and by overcoming considerations arising from the use of dissimilar metals.  Minimising the risk of welding defects and subsequent rework during the shutdown is important to avoid costly delays. Use of the compact flanges has reduced the number of the field welds on this project by 60%.

The light weight of the SPO Compact Flange is also a significant advantage, given the location of the flanges (15 metres high and inaccessible, while those installed during 2004 are at a height of 25 metres above ground level).  The SPO Compact Flange design makes it considerably smaller and typically 70-80 per cent lighter than a traditional ANSI flange for the equivalent pressure rating.  By overcoming the need for heavy lifting equipment and challenges presented by a congested site with severe space restrictions, the SPO Compact Flange offers valuable time and cost savings.

Particularly significant is NZRC’s need for leak-free connections – which the SPO Compact Flange meets with its unique no-leak sealing technology. Cyclic thermal expansion and contraction resulting from planned and unplanned outages heightens the risk of gasket failure over time when using ANSI flanges for joining dissimilar metals.  Given the height and inaccessibility of the flange locations, design and installation of permanent access platforms would have been required for inspection and maintenance if ANSI flanges were used.  However the SPO Compact Flanges offered a cost effective alternative, negating the requirement for access platforms due its capability to maintain seal integrity in such conditions.

The SPO flange design uses a wedging action with radial compression to ensure a rigid, full contact seal between the faces which remains static regardless of load conditions, resulting in a connection that combines the integrity of a welded joint with the versatility of a mechanical one.  In over 80,000 applications worldwide the SPO Compact Flange is said never to have leaked in service.

“Because the height of the flanges means they are inaccessible during normal operation and would require scaffold erection for maintenance (with time, cost and risk implications), NZRC wanted a reliable high integrity low maintenance flange, rather than standard ANSI weld neck flanges, to safeguard against leaks under operational conditions,” Vector Australia business development manager Jim Friel stated.  “Using SPO Compact Flanges means they can install and leave them with the confidence that they won’t leak, and won’t need attention.  These flanges feature built-in protection from sealing fatigue and corrosion with no need for periodic bolt re-tightening, so have minimal through-life maintenance needs – representing on-going savings.”

Commenting on the project, Transfield Worley Ltd senior mechanical project engineer Mal MacLean said: “We’ve had no leaks or corrosion problems with the first batch of compact flanges, which have been in-service for three years now without requiring any maintenance, so we feel confident about using the same flanges again for the upgrade to the convection bank.  NZRC also wanted the capability for mechanical decoking of the coils.  Incorporating the SPO Compact Flanges into the design gave us the means of access for future pigging operations, whilst maintaining confidence in joint integrity.”

Compact connection and sealing specialist Vector International has recently established an office in Australia, serving Australia and New Zealand.  Its range of compact connection technology, including the SPO Compact Flange, Techlok clamp connector and Optima subsea connector, are widely applied across the world for pressure containment applications in a broad span of industries, from oil and gas, mining and minerals processing to power generation among others.