The BaBar Upgrade Load transfer of the Barrel and Endcap Calorimeters Richard F Boyce 21 October 2003

The Barrel Calorimeter is just inside of the solenoid coil and the Endcap Calorimeter is just inside the forward door (right side)

The Barrel Calorimeter in supported by four arms which are attached to the Flux Return corner plates The Forward Calorimeter is bolted to the Barrel Calorimeter

The southeast support arm

Looking up at the southwest support arm

Corner plates with notches for the calorimeter support arms Barrel Calorimeter alone shown

The Rules The corner plates must be taken off to allow the RPC’s in the 4 side sextants to be removed. The Barrel and Endcap Calorimeters must be held up by something other than the support arms. The load transfer must not move the calorimeters or put unusual loads on the pins.

Extra pins in the Barrel Calorimeter for installation Support pins

2 inch thick plate bolted on top of the gap plates Grout to floor

2 inch thick plate bolted across to reach the extra pins

Close-up of lower west extra pin - notice that access is limited (we need to look at the upper pins)

How to engage the extra pins? How to lift and transfer the load?

The holder need to minimize the moments on the pin

Can a spherical bearing be used as the fulcrum? Can a 2 inch plate resist the twist?

Front view Notice the horizontal plate is larger and moved down

Summary The loading would prevent squeezing the pins together and creating new forces. One pin could be used to control the lateral motion. Adjustments are straightforward. There would need to be dial indicators to control the motions and load transfer. As the turnbuckles are tightened the support arm would have to be relaxed. Watch the flexing of the tooling.