LDX May, 2001

Floating Coil Helium Vessel and Cryostat

Ability Engineering Technology has competed the final welding of the Inconel 625 Helium vessel. Ultrasonic inspection of the welds have been completed and approved. Initial vacuum leak checking indicated no discernable leak of the welds. Preparations have been made for the final full pressure test of the vessel and the test will commence after the cryostat anti-rotation device brackets have been attached.

Connecticut Coining, Inc. has delivered the 7500 coined disks that will be the major component of the low heat leak supports that separate the helium vessel from the outer cryostat wall.

Charging Coil

Alex Zhukovsky visited the Efremov Institute (Russia) at the end of March. A project schedule was developed according to which the coil in the cryostat, along with the quench detection and quench protection systems will be delivered to MIT on November 15, 2001. The schedule was signed by Dr. Oleg Filatov, director of SINTEZ. Beginning in April, progress of the project has been under weekly review by Dr. Filatov. Additionally, some necessary changes in the assembly drawings were made.

Zhukovsky also had meetings with the Efremov staff and with Dr. M. Larin of Cryovax (a vendor involved in the C-coil manufacturing). Dr Larin displayed a full size roll of the processed stainless steel tape that will be used in the C-coil cryostat to reduce radiative heating. The tape has an innovative, highly reflective aluminum covering.

The vacuum impregnated dummy coil is ready for a cold test in liquid helium, scheduled for the end of May. The performance of the conductor and the joint performance will be tested at the full operating current. A high voltage test at 7 kV to the ground will be performed to check a quality of the electric insulation system in cold helium vapor. The mechanical integrity and physical properties of the impregnated coil will be checked after the test.

A first test of the coil clamp was completed, and this resulted in minor changes in the clamp design. The modified coil clamp has been completed. The large parts for the tooling for the C-coil winding have been ordered for manufacturing. The Cable Institute in Moscow has made about 80% of conductor needed to wind the C-coil.

The latest version of Interface Control Document was sent to MIT for our approval and comment.

Alex Zhukovsky is going to visit Efremov at the end of May to check the progress of the project, the adherence to the schedule, and to examine the dummy coil after the test.

Levitation Coil

Design and construction of the LDX L-coil is being funded largely via SBIR funding involving MIT and the American Superconductor Corporation. MIT lawyers and ASC lawyers have not yet come to agreement on intellectual property right issues related to this and other joint activities on the MIT campus. Up to this point, these legal issues have not impeded the progress of the L-coil. A reference design for the L-coil winding and cryostat was completed and send out for quotation in late March. There were four responses for the cryostat design and fabrication and one response for the winding design and fabrication. In late April we met with Everson Electric Company (who bid on both the winding and cryostat) to discuss various design options aimed at reducing the cost of their proposal and a revised bid was received from Everson on May 9. We expect the L-coil manufacture to be complete by October, 2001.


Alex Hansen visited Hollis Line Machine on May 11 to inspect their facilities and to deliver the launcher bellows purchased from Standard Bellows. Fabrication of the launcher is proceeding. The right angle box is nearly done, and the parts for the upper and lower drives are cut out

Diagnostics and Controls

The computer systems that will monitor and control the floating-coil position have been received. The system includes a computer running a real-time operating system, hardware for data acquisition, timing, and control signals, and a second computer for development and operator interface. An integrated test of the equipment has been successfully completed.

The components for the first of eight laser-based optical position detection diagnostics has been received. Testing and calibration of this diagnostic will be the subject of study for an MIT undergraduate research student over the summer recess.

The hard x-ray spectrum analyzer diagnostic has been constructed and testing and calibration is in progress. The 2 channel system (upgradeable to 4) is capable of measuring photon energies from 1 keV to 1 MeV at count rates as high as 1 MHz.

The integrating amplifiers for the 32 channel magnetic diagnostic systems have been completed and calibrated. The magnetic pickup coils and loops are now being designed and will be installed this summer.