Switchyard 120 Main Ring Quadrupoles

The Switchyard 120 (SY120) beam line uses five refurbished Main Ring quadrupoles in the Tevatron enclosure, two 84" quads and three 52" quads.  An oval beam tube is inserted through the quads, as was done in the Main Injector.

The basic rework will consist of the following:

• Remove existing support structures
• Remove existing flanges, bellows, end cans, etc.
• Purge water passages with Rydlyme
• Replace insulators and manifolding
• Add Main Injector style support feet
• Add standard fiducials
• Perform electrical and water tests
• Paint and label
• Perform magnetic measurements

IQB (84" quads)

The 84" quads will be IQB style (ME-331912), reworked to match (mostly) the quads reworked for use in the Main Injector ring, and will draw from the same pool of spares.

IQB226-1  In the Main Ring this magnet was 7226.  It was not reworked for the Main Injector due to its having a slightly elevated radiation level and there being a surfeit of IQB quads.  We plan to make this a standard IQB, including the BPM plate, for the sake of uniformity.  If the plate interferes with installation in Switchyard, we should at least leave enough of the original beam tube to allow later installation of a BPM plate.

IQB321-1  This magnet was known as 7321.  It has no Main Ring style star beam tube and never did.  Although this will be designated an IQB, we will not attempt to retrofit a star beam tube nor a BPM positioning plate.  This will be documented in the traveler, through a Discrepancy Report, in the Device Service Record, and on the magnet.  If this magnet fails, it can be replaced by a standard IQB spare and in the course of reworking be converted to any style desired.

IQJ (52" quads)

The 52" quads will be reworked to style IQJ (ME-388152) - a new designation - and will require one spare in addition to the three being installed.

The IQJ magnets are made from an early version of the 52" MR quad that has two parallel water paths (top and bottom), rather than the later four parallel paths.  While the reduced length of the 52" quads compared to the 84" quads gives a reduced power consumption at the same current, the water flow is reduced even further, leading to an increased temperature rise in the cooling water.  This is not an issue for the 120 GeV levels at which the magnets will be run in SY120, but they probably should not be run DC at the equivalent of 400 GeV.

The 52" quadrupoles identified as rework candidates were 4076, 4079, 4083, and 4085.  They became IQJ076-1, IQJ079-1, IQJ083-1, and IQJ085-1, respectively.
 

Back to Switchyard 120 Magnets page.

Last Updated on 30 August 2004
By Emily Tam

Author:  David Harding

Contact: Oliver Kiemschies
Email:  ollie@fnal.gov