Tip of the week
Tip 2 - July 2011
Body (girth) flanges have
distinct advantages in small columns (Part 1)
Koch-Glitsch, LP

Small-diameter columns (typically smaller than 36” diameter) can impose unique equipment design and installation constraints compared to larger columns. Installers cannot easily enter these columns to perform installation, and limited access makes hardware connections difficult to complete.  Furthermore, internal supports tend to block an increasing percentage of the column cross-section as the diameter decreases, and it becomes more difficult to install them. In these situations, an effective approach is often to divide the column itself into smaller segments through the use of body (or girth) flanges at strategic elevations along the height of the column.
Using body flanges makes the full column cross-section accessible without the use of manways, removing many installation constraints that would otherwise be created by the small column diameter.  Because the flanges break the column into segments, the column itself may be erected one segment at a time rather than all at once, potentially reducing the lifting equipment requirements and the amount of space required for column set-up.  Depending on the method of securing the equipment in the column, it may be possible to install it in the vertically oriented column segments at ground level and then raise the segments into place.  NOTE: Once the internals and/or packing are installed, the column segments must remain vertical. Equipment installation time can be further reduced by performing simultaneous installation of the equipment in each column segment.  Thus, body flanges can significantly increase the speed and safety of installation while reducing its cost.

With a body flange design, it is often possible to reduce the number of internally welded tower attachments, as the equipment can be made either to be sandwiched in the flanged connections themselves or to rest on separate rings made to mount in the flange joints. This is a particularly useful approach for structured packing installations, which often use single-piece packing layers for small diameters and require a completely open cross-section.  Future changes in equipment configuration are also easier to accommodate and tend to require less column rework if body flanges are used.

Read Part II to learn more about the design advantages to using body flanges. 
Need more information? 
Contact your Koch-Glitsch representative to discuss your application.
Visit the Mass Transfer and Separations Technology sections of the Web site to learn more about our products, the industries that we serve, and our applications knowledge.
Koch-Glitsch offers a complete line of mass transfer and separations technology products for a wide range of applications.   
 July 2011
 June 2011
 May 2011
 April 2011
 March 2011
 February 2011
 January 2011
 December 2010
 November 2010
 October 2010
 September 2010
 August 2010
 July 2010
 June 2010
 May 2010
 April 2010
 March 2010