Plascore Panel Locations

1
Plascore Panel Locations
2
Each Cell is a Chamber consisting of (7) Plascore
Panels

• The Outer Ring panels are 1.5m x3.0m
• The Inner Ring panels are 1.2-1.5m x 1.5-1.8m

3
Panel Construction

• .06T FR4(Epoxy/Glass) with Copper Cladding
  Facings
• Epoxy Adhesive
• Plascore PC Honeycomb

4
Typically Cut, Milled and Drilled Panels
5
Wound Anode Panels
6
Chamber AssemblyStack of 5 Plascore Panels
7
Finished Fully Framed Chamber
8
1. Plascore was involved in making the
fundamental components in the Endcap Muon
Chambers that are shown at both ends of the
Compact Muon Solenoidal Detector for the Large
Hadron Collider (LHC). There are 198 chambers
used in each Endcap. Each chamber uses 7 panels
of a given size. In total Plascore was asked to
produce panel sheets for 410 production chambers,
15 prototype chambers, plus 5 spares. In total
about 600 4x12 panel sheets and about 1600
5x12 panel sheets were produced for chamber
development and production. Fermilab has taken
these panel sheets and cuts them into over 3000
trapazoidal panels for use in finished
chambers.2. Photo shows each chamber in its
place on the steel disks that make up each
detector muon endcap system. This is where all
the 3000 trapazoidal panels are used.3 Plascore
was chosen as the Vendor of choice because we had
the ability to produce lightweight, ridged panels
of uniform thickness over the whole of the panel
area, and consistent in quality and dimension
from one panel to the next, all at a reasonable
cost. The basic panel structure consists of
copper coated FR4 skins 1.5mm thick (Std. Ckt Bd
Matl) separated by an extremely uniformly cut PC
honeycomb structure that is glued to the backside
of the skins by epoxy. The PC structure and the
epoxy system was sought after because of its high
radiation resistance, strength, and light
weight.
9
4. In order to accurately machine the required
design features into the copper clad skins of the
cut panels, the panel surfaces had to be
extremely flat. Even though the cutting head of
the machine mills away the surface copper tends
to float on the copper surface, only very gradual
variations in flatness could be tolerated. By
maintaining surface flatness to the
specifications we were given, the maching depth
of cut was able to be maintained at between about
0.004 and 0.008.5. Another reason for having
a flat, strong, and stiff panel was so that the
spacing between the anode wires and the panel
surface would form two uniformly spaced surfaces
so that the electrostatic field would be very
uniform, allowing the gain variation to be very
small. 6. For this picture, I suggest using the
one I sent you showing 7 panels stacked. The
one you have chosen shows only 4 panels. Of
interest is the fact that the panels are stacked
with separators around the perimeter with only a
few small separators needed along the center axis
in order to maintain a very uniformly consistent
space between panel surfaces. The panel
construction prevents localized bowing which
could create the problem of non-uniform spacing
between panels.7. The PC structure of the panel
cores had to be strong enough that it would not
crush or creep under the stresses caused by the
frame structure that holds all the panels
together. The photo shows all panels held
together by the frame structure, with all bolts
in place. All perimeter bolts are torqued to
50-60 in-lbs.