LDX Project Status
November 25, 2002


Ability Engineering Technology in South Holland, IL continues with the final assembly of the floating coil cryostat.

A flow test of the cooling tubes in the shield indicated that the two halves were well matched and that the resulting flow rate was consistent with previous measurements. High reflectivity 3M 425 tape (aluminum foil with acrylic adhesive backing) was applied to the helium pressure vessel and to the inner surface of the lead shield. Final thin walled tubings were installed on the He vessel heat exchange ports and the He fill line and valve were installed. Four Cernox thermometers were installed on the surface of the He vessel. Special Mylar cages were made at MIT for the 16 borosilicate glass balls that support the shield on the helium vessel. The balls were installed between the cups located on the Inconel vessel and the shield. The Helium vessel and shield were thoroughly cleaned and the shield was installed. The two shield halves were sealed with epoxy bandages and the heat exchange tubings were connected.

The rotary table bearing, for the charging station, has been completed and tested and the bearing nose has been installed on the cryostat vacuum shell. Installation of the ports for the heat exchange bayonets and electrical feedthroughs has begun.

The inlet helium transfer line was sent to Quality Cryogenics for improvement in agreement with suggestion of the MIT engineering group. The transfer line bayonets were wrapped with super-insulation, welded, and leak tested successfully.

Vessel and lower shield sitting on lower support bolts. All through tubing is in place.

Vessel and lower shield sitting on lower support bolts. All through tubing is in place.


The coil was installed into the partially assembled helium vessel. All supports of the coil were permanently adjusted. The current leads were successfully tested at high voltage (up to 4.2 kV) at both room and at liquid helium temperatures. The current leads and all instrumentation were permanently installed. The inner helium vessel cylinder was welded and is being rolled to bring it to the correct size. The final welding of the helium vessel (enclosing the coil) has started. The upper and lower copper shields were adjusted in the nitrogen cans. The shield sectors were welded to radial stainless steel strips (for interruption of eddy currents) and polished. The lower shield was sent to a subcontractor for the installation of cryopanel copper getter boxes that contain charcoal. The inner and outer nitrogen cans with all welded fittings were readied for the final assembly into the cryostat. The inner vacuum vessel cylinder has been machined to the size. The outer cylinder has been spot welded to the cryostat cover. The vacuum vessel parts are all ready for final assembly.

The Sintez stand is being prepared for the final charging coil test. The testing procedure document, is now being agreed and has been sent to MIT. Sintez has finished the design of the shipping container for C-coil. Helium Vessel assembly

Helium Vessel assembly


Everson Electric has placed purchase orders for about half of the outstanding cryostat components, with typical delivery dates ranging from Nov. 11 to Nov. 21, while the other half are being circulated for quotation. As Everson has staged the procurement activity to follow the order of the cryostat assembly; this should result in components arriving as needed to proceed with assembly.

A work area has since been laid out and preliminary assembly work has begun on the vacuum vessel and nitrogen reservoir.


The major parts of the lifting assembly have been electropolished. The upper mechanical drive has had its internal vacuum-facing surfaces cleaned.