Engineering Design Review for TRD-Readout Chamber Mechanical Design Bernd Windelband University of Heidelberg

TRD and TPC in Space Frame

ROC Segmentation in Individual Layers

Different Types of ROC‘s ATRD0901P6 16 different types of ROC‘s from 1080mm x 974mm x 105mm, type L1C0 to 1585mm x 1196mm x 105mm, type L6C1,

ROC L6C1 (1585mm x 1196mm)

Mechanical Requirements of ROC to keep wire tension (~90kg) and drift gas overpressure (1mbar) to ensure required flatness of padplane (<200µm) and radiator (<1mm)  very rigid structure small radiation length („made out of nothing“) radiator and pad- readout panel have to be sandwich structures

ROC Cross Section, View in z each chamber consists of 48mm radiator 37mm drift volume with wire planes ~20mm backing structure with pad plane main frame with radiator serves as the main support structures to hold the wire tension. pad plane does not see the wire load.

ROC Cross Section, View in φ Pad- Readout panel Voltage Divider Frontplate with Chamber to Chamber Sealing Connection

Chamber to Chamber Sealing Connection Quad-Ring-Seal unit glued to frontplate connection with PEEK tube, di=17mm serves at the same time as chamber to chamber alignment

Thickness Determination of the CF-Layers for Pad- Readout Panel and Radiator 20mm core thickness fmax <= 200μm Result: 0.4 mm f = (c3 · p · b4 )/(6 · ED · t · (t + c)2) t = thickness of carbon fibre facing, p = pressure load c = thickness of the core material, ED = Young’s Modulus of the layer, 2a = panel length, 2b = panel width, c3 = correction function (a/b, load case). Radiator, 48mm core thickness fmax <= 1mm Result: 0.1 mm case 1 =clamped case 2 = simply supported

Full size Prototype L6C1 Chamber Components – Production and Assembly Pad- Readout Panel -> INVENTOR (Krakow) -> PI Uni Heidelberg (cutouts, glueing of pad planes) Radiator -> INVENTOR (panels) -> IKP Uni Muenster (assembly) Main frame, wire ledges, etc. -> PI Uni Heidelberg (production and assembly) Three main production steps: glueing main frame to radiator electrical connections and applying the wire planes closing the chamber with pad- readout panel

ROC Prototype L6C1, Radiator

ROC Prototype L6C1, Test Assembly

ROC Prototype L6C1 Main Frame glued to Radiator

ROC Prototype L6C1 applying additional layer of glue along the rim

Purpose of L6C1 Prototype Load from wires and drift gas pressure most critical for largest chamber Verify design of largest chamber -> L6C1 behavior of main frame under wire load deformation of pad- read out panel and radiator under overpressure to learn assembly procedure and application of the wire grids test of chamber performance (Harry)

Wire Tension Test

Wire Tension Test - Detail

Measurement of the Deflection

Deflection of Chamber Side Profile under Wire Tension

ROC Prototype L6C1 voltage divider

ROC Prototype L6C1 applying the wire planes

Wire Tension on Winding Frame and on ROC

Padplane for Prototype connector side Pad side

Prototype on Test Stand

Further Results of Tests Chamber main frame deformes 150 μm under wire tension indicated in TDR -> 10% loss in wire tension. Additional tooling necessary for chamber assembly -> mounting table for chamber frame. -> computer aided measurement sytem Deformation Pad- Readout Panel and Radiator under overpressure within the requirements (talk of Harry and Damian). Large capacitance between Carbon fibre layer close to padplane and padplane -> replacement of this CF-layer by insulating material (glass fibre, Kevlar).

Infrastructure for Chamber Production mounting tool for the chamber main frame and glueing to radiator flat tables vaccumtable (glueing pad plane to pad- readout panel) cleanroom and wire winding machine (to produce and glue the wiregrids to the chamber) milling machine with min. 1,6m machining length (production of chamber main frame parts) computer aided measuring system

Mounting Table for ROC

New Wire Winding Machine

Glass Table and Crane in the New Cleanroom

Refurbished Milling Machine

Computer Aided Measuring System (Hecht) -> System will be adapted to our table size and specific needs

Next Steps Production of Chamber Stack. Production of Chamber Mounting Table. Test of Pad- Readout Panels with Kevlar, Kevlar-Tedlar and Glassfibre layer instead of CF. Final Set up of Cleanroom Installation of Measuring System