Segmenatation of STAR Pb Radiators


Pb radiator components segmentation vs towers

The following drawing shows the first layer of scintillator megatiles superimposed on the the 1st radiator. It shows the segmentation of the Pb and the stainless steel front and back as currently drawn. In the local meeting today we decided to alternate the bevelled edge in the center of the radiator back and forth over the tie rod. For the butt joint we will try to shift it by 2-3cm layer by layer in a pattern of 3, i.e. +2 0 -2 +2 0 -2 etc. This pattern should fit without crossing too close to the tie rod positions.

dxf file (autocad) of the radiator segmentation
eps of the radiator segmentation with notes not in dxf file

The following drawing shows the bevelled and butt joints. Tolerances on the straight edges are likely to be about .005". So if the high points actually touch (an assembly question yet to be prototyped), gaps along the butt joint would vary from 0 to .010". Note this would also be true along the bevelled edge. Note the bevelled edge has the sharp corners broken so that there is a triangle of material missing on each piece. The material thickness is +/-.1mm. Thus there are likely to be places where the two adjoining pieces of the Pb are at opposite ends of this tolerance. This could, in fact, be systematic since Pb plates are expected to be crowned, i.e. thicker in the middle than at the edges.

dxf file (autocad) of the joints
eps of the joints