1m 3 SDHCAL Mechanic Structure M.C Fouz 8/10/2010 The 1m 3 prototype Mechanical Structure is financed by: Spanish HEP National Program by the project FPA

08/10/2010 OUTLINE  The design  Quality Control tests  Assembly tests and tooling  Schedule and costs M.C Fouz2

General requirements absorber plates (stainless steel) interleaved with the detector cassettes. 20mm passive absorber material, including the cassettes. The mechanic structure should allow to accommodate GRPC as well as MICROMEGAS (It will be instrumented first with GRPC but it was planed to built some MICROMEGAS that must be tested on the same mechanic structure) It must allow the insertion and further extraction of the cassettes The prototype not only must prove the technology and serve us to get experience on the operation and performance but also on integration and technical issues of building an ILC-like module. 08/10/2010M.C Fouz3

Towards a Technological Prototype Barrel Module 08/10/2010M.C Fouz4 The aim is to build a realistic prototype as close as possible to the solution proposed for the ILD concept.  Validate the technological solution Self-supporting mechanics Minimize dead zone One-side services Module ILD - SDHCAL LOI design

Towards a Technological Prototype Absorbers will be assembled together using lateral spacers fixed to the absorbers through bolts. Technological prototype : 40 detector plans of 1m 2 : 20mm stainless steel (absorber + cassette support) 6mm GRPC 08/10/2010M.C Fouz5 Cassettes. Electronic side Absorber plate Spacers The dead spaces have been minimized as much as possible taken into account the mechanical tolerances (lateral dimensions and planarity) of absorbers and cassettes to ensure a safe insertion of the cassette. Design independent of the detector technology to be used (RPC and MICROMEGAS)

Absorber Mechanic structure – Details Spacers Absorber Bolts 08/10/2010M.C Fouz6 Absorber Plates: 1011 x 1054 mm 2 lateral dimensions 15 ± 0.05 mm thick Surface Planarity < 250  m Spacers: 13 mm thick Material: Stainless steel 304L (permeability, as measured, 1.5  it allows used it in B=4T) 2x11 bolts/plane M8

08/10/2010 Simulations Detailed study has been made to evaluate the robustness of this structure in different positions. It is important to evaluate the deformations and the stress that the structure can suffer when moving and rotating, the deformations will be also transferred to the GRPC detector ANSYS numerical simulations performed on the deformation and stress Max. deformations don´t exceed 150 microns. The punctual max. stress it is only 74 Mpa, well away from the elastic limit of the material The max. reactions on the M8 bolts are: Fx= +/ N, Fy= N, Fz= +/ N M8 bolt have the elastic limits, function of the material, between about N to N. This is the situation more adverse for the M8 bolts. M.C Fouz7

Plates & Quality Control To reduce the gaps it is needed a good planarity of the absorbed plates. The tolerances of the standard market are higher (several mm) than our needs(hundred of microns), the plates need to be further machined to achieve the precision we are interested in It is not easy to achieve the precision. Tests done at different companies to find a supplier that guarantees our needs. Quality control during the mass production of the plates will include verification by the company, both of the thickness and the planarity, and then a crosscheck will be performed at CIEMAT by using a laser interferometer system (Precision  m for the planarity measurement).. 08/10/2010M.C Fouz8

Plates - Planarity measurement procedure 08/10/2010M.C Fouz9 Support pins 3 pins support the plate In order to disentangle the planarity measurement from the table shape Pin

Plates - Planarity measurement results 08/10/2010M.C Fouz10 a) Theoretical deformations computed for the plate supported by the three pins. b) Laser measurements of the surface of a real plate c) Surface plate planarity computed as b) – a) a)b) c) Pin location Pin location Pin location Planarity values

Plates - Planarity measurement errors 08/10/2010M.C Fouz11 In order to check the accuracy and stability of the measurements the same plates have been measured several times in the same conditions and also supported by the pins in different positions. The differences between the different measurements are inside the  m error provided by the laser interferometer system. Differences between two measurements of the surface plate performed with support pins in different positions with respect to the plate. For both surfaces of the plates. Surface ASurface B

Assembly tests & tooling Suction pad A specific tool for handling the plates has been designed and built Security System Special table to support the 6ton prototype 4 absorber plates (bad quality) assembled to test the procedure The mechanical structure should be finished by march /10/2010M.C Fouz12

Rotation tool 08/10/2010M.C Fouz13 The 1m3 prototype is a heavy structure (~8500 Kg) that we need to move and eventually rotate (for cosmic tests at the lab for example). Tool under design now

Schedule & Costs 08/10/2010M.C Fouz14 Timing: The most time consuming is the verification of the plate planarity  Manipulation of the plate  Regulation of laser for each measured line ~2.5 – 3 hours/plate At least 30 plates must arrive to CIEMAT before the end of the year The structure should be finalized by March 2011 Cost: ~ 3000 euros /plate ~1000 euros for material the rest is for machining Due to the relation between the final dimensions of the plates and the standard dimensions provided by the market it has some extra cost The cost of the other components and tooling are marginal with respect to the plates It is financed by: Spanish HEP National Program by the project FPA

08/10/2010M.C Fouz15 BACK UP

Towards the 1m 3 prototype: GRPC Mechanic structure - Cassette DIF Thickness adjusted to be the same as Micromegas cassettes Cassette to include the GRPC detector and associated electronics Horizontal Vertical Max: 0.5mm Max 5.9 x mm Deformation under its own weight as a function of storage orientation Successful insertion from above aperture 12.5 mm Cassette insertion test 08/10/2010M.C Fouz16

Towards the 1m 3 prototype: Absorber Mechanic structure – First ideas g rav ity DIF Each detector module it is supported on the absorber by 6 wheels fixed on the cassette support of the detector. Details of the guiding system. The rails are fixed on the absorber. Absorber Attachment device Are fixed on the top and bottom spacers. cassette DIF This design is not suitable for a “final” detector: - Too much dead spaces - Expensive 08/10/2010M.C Fouz17