In May, the Gamma-Ray Energy Tracking Array (GRETA) project achieved a significant milestone with the move of the two mechanical assemblies that comprise the array structure. These structures moved from their assembly location in the high-bay of Bldg. 88 to the laboratory ‘K-area’ space where they will be integrated with the other technical systems of GRETA in the coming months.
This move happened in the beginning of May over the course of two days. Following detailed planning over several months with the LBNL rigging team led by Curt Howard and Taylor Silva, including the procurement of dedicated gantry cranes and measuring far more than twice, the move started bright and early at 8am on May 7, 2024. The planning more than paid off with an impressively smooth move of these >6000 lb assemblies. Figures 1 through 5 show a story-board of the move of the first structure. A lift onto a flatbed truck in the Bldg. 88 high-bay started the action, then travel around the building followed. A truck-mounted 50-ton crane was used to lift the structures off the flat-bed and to perform the delicate drop through the double doors into the K-area. The GRETA structures were then rolled into position alongside their final places and a coordinated lift and slide of the structures using the dedicated pair of gantry cranes completed the move on to the prepared plates. The pair of installed structures is shown in Figure 6. The LBNL riggers with support from the local Bldg. 88 mechanical crew, in particular John Garcia and Brian Bell, executed this complex move perfectly, twice.
Over the coming summer months, the GRETA structures will be built up with motion and cooling systems, aligned, and then load tested. Six GRETA Quad Module HPGe detectors will be installed in the August-September timeframe to demonstrate the performance of the array prior to completion of the DOE project and its ultimate delivery to the Facility for Rare Isotope Beams (FRIB) for scientific operation.
NSD scientist Paul Fallon is the GRETA Project Director and Heather Crawford is the manager for GRETA System Assembly, with staff from NSD and Engineering Division at LBNL, and from ANL, ORNL and FRIB on the project team.
Figure 1: The first half assembly of the GRETA mechanical structure being craned in the Bldg. 88 high-bay onto a flatbed truck for transport around the building.
Figure 2: The mechanical structure loaded on the flatbed and ready to roll with NSD DSC Jeff Bramble looking on.
Figure 3: The first half assembly staged on the west side of Bldg. 88 and ready for craning off the truck and into the K-area.
Figure 5: The first of the two GRETA mechanical assemblies being slid over on dedicated gantry cranes onto the prepared mounting surface.
Figure 6: The final pair of installed GRETA mechanical assemblies in the K-area at Bldg. 88.