LDX Project Status

January 5, 2000

Helium Vessel

On December 15 Alex Zhukovsky and Darren Garnier visited Ability to discuss the progress of work being done on the LDX floating cryostat. Ability has completed the welding of the two halves of the Inconel helium vessel and both halves were successfully examined by x-ray. The dummy winding coil form fits nicely in the half-helium-vessel. Quality, shape and surface finish of the helium vessel parts are good. The welding fixture for the helium vessel and necessary gussets have been made. The practice Inconel half elbows were machined for the final equatorial welding, which will be performed with installed dummy coil form and two coil supporting gussets. The final welding procedure for the helium vessel will be developed according to this welding test.


Floating Coil Cryostat

Several fiberglass radiation shield models were build at the PSFC using a vacuum bagging technique. D. Garnier and A. Zhukovsky discussed the fiberglass shield technology with the ability engineers during the December 15 visit. Ability agreed to build a prototype of the shield using the MIT methods and the final materials and to test it on the Ability toroidal octant mold. Garnier will visit Ability from Jan 10-12 to oversee this prototype manufacturing. Pyrex 12 mm balls for the final shield supports as well as Borosilicate balls were delivered to Ability to be used in the shield models. Ability received drawings for tooling of the vacuum shell spinning from Kosemple Co. The quote for the tooling only is $8700, which is higher than their preliminary quote. Ability will consider a possibility to make tooling at Ability for a lower price. A sketch which indicates position of the F-cryostat in the charging station was given to Ability. Ability is performing preliminary design of the charging station and transfer line bayonets.


Floating Coil Winding

Soldering repair was successfully completed for the entire length of the LDX F-coil conductor. This procedure removed the ripples that had previously been identified as the source of significant reduction in the conductor's critical superconducting properties. During December, a practice winding of the floating coil was performed at Everson Electric using dummy conductor with the same dimensions as the production conductor. Sufficient dummy conductor was available to perform a partial pancake winding and two layers of layer winding with the protective copper sheet soldered between layers 1 and 2. The main accomplishments and lessons of the practice winding were:

  1. The identification of an improved approach to forming and holding the pancake-to-layer winding spirals to prevent excessive conductor strain.
  2. The demonstration that the main conductor spool can be moved successfully from the winding machine to the payoff station without damaging the conductor.
  3. The demonstration of a successful approach to machining and installing the layer-to layer turn transitions.
  4. The demonstration of a successful approach to assembling the soldered joint in the protective copper sheet which is located internal to the coil.
  5. The identification of the need for the fabrication of winding guides to start each major step of the winding.
  6. The demonstration that the winding machine tooling, including the winding machine, taping heads, and payoff station, are appropriate for the job.

Winding of the production LDX floating coil was started on Jan 6, 2000, with the back winding of the pancake portion (about 400 feet) of the conductor. It is expected to be completed, including vacuum impregnation, testing and shipping by the end of Feb 99.



The preliminary design review for the Launcher/Catcher was held at PPPL on January 5, 2000 via video conferencing. Bob Ellis, Phil Heitzenroeder, Stuart Zweben and John Schmidt participated at PPPL. Bob Ellis presented the design that he has done on the launcher. The design entails a center rod that passes through the floating coil and two wheels that are attached to this rod that limit the motion of coil along the rod. The review was a success, and the schedule for the final design review will be set shortly. It is expected that the requests for bids will be send out in February and the launcher/catcher will be delivered to the LDX cell in April.


Very intensive communications with potential manufacturers of the C-coil were completed successfully and the Efremov Institute (STC "SINTEZ" ) in St. Petersburg, Russia was chosen to be the vender of the coil. Efremov presented the most developed proposal and offered for the lowest bid. The final statement of work for production of LDX C-coil was issued at MIT. A visit to the Efremov Institute by Alex Zhukovsky and Darren Garnier was scheduled for mid-January, 2000.

Webmaster: D. Garnier
Last updated: Tue, Apr 25, 2000