1 Space-Frame Endplate Design and Construction for LP2 and ILD Dan Peterson Laboratory for Elementary-Particle Physics, Cornell University LCTPC-Peterson

2 Cornell is building a next generation, space-frame, endplate for LP2. It is interchangeable with the LP1 endplate delivered in 2008.

LCTPC-Peterson gas HV field cage termination mount channeling of mullions between strut mounts space-frame endplate main plate after first machining step It is currently at the vendor for 3rd / final machining step.

LCTPC-Peterson Several studies have preceded this design FEA of ILD equivalent plate design radius 1.8m, thickness 100mm, material 6% X 0 support at inner and outer field cages deflection = 0.22mm for 2.1 mBar

LCTPC-Peterson Study of space-frame solid model predicts favorable rigidity/material. Measurements of existing endplate validate the FEA. mass material deflection stress kg %X 0 microns Mpa (yield: 241) LP Lightened Al-C hybrid Al (68-168) ( ) (channeled plus fiber) C 1.29 Channeled Al Space-Frame (strut or equivalent plate)

LCTPC-Peterson mass center load center load center load center loaded FEA MEASURED MEASURED MEASURED mm/100N mm/100N mm/100N mm/100N LP kg Al-C hybrid ( 1.0 part fiber : 1 epoxy ) 1.71 Al-C hybrid ( 0.25 part fiber : 1 epoxy ) 2.12 LP1 (channeled) 0.37 kg (channeled for the hybrid, but without adding carbon fiber) space-frame (“strut”) 0.76 kg space-frame (“equivalent-plate”) Sections of the LP2 endplate were constructed and measured, validating the FEA and demonstrating the equivalence of the “equivalent plate” design.

LCTPC-Peterson bolt-on interchangeability with the LP1 endplate 8.4 kg vs kg 144 precision adjustable struts remove machining imperfection build-up.

LCTPC-Peterson bolt-on interchangeability with the LP1 endplate Accepts current Field Cage Termination. Accepts current Module Backframes. Does not have “fun holes”; must use the mounting holes to the field cage.

LCTPC-Peterson The LP2 endplate accepts LP Module Backframes. Revised Mounting Brackets are being manufactured to adapt to the LP2 endplate. Clearance around the strut mounts is required. Lightened Module Backframes have about 50% mass and provide more access to the back of the pad board. These require a different Mounting Bracket.

LCTPC-Peterson Assembly will require a flat plate (shown) and positioning fixtures. These are in-design, and will go into manufacture in about 2 weeks.

LCTPC-Peterson Schedule and Costs Endplates (2) Backframes-2008 (0) Backframes-Lightened (9) (Backframes are “3GEMG”, meaning they accept 28mm of pad board, gas-amplification, gate.) MountingBrackets (2008 Backframe on LP2 endplate) (18) MountingBrackets (Lightened Backframe on LP2 endplate) (8) _______________ $ All parts are expected to be completed by the end of August Construction may be completed by the end of October 2011.

LCTPC-Peterson Previous FEA studies concentrated on longitudinal rigidity. This does not directly address our concerns. More important is the accuracy and stability of the mounting locations. One of the endplates will be kept at Cornell for further testing. In particular, I am interested in transverse rigidity and long term stability and if transverse strain will result in deformations at other locations. Future FEA will investigate issues related to larger modules.

LCTPC-Peterson Personnel and Funds Equipment funds no new funds, I am not saying how much is left. We are currently requesting another extension beyond July 31. Salary Funds expected 3 rd year, starting August 31, 2011, ~30-40% The annual report is accepted (Tuesday); new funds are “pending”.