PANDA Yoke unsolved Interface problems Presented by E. Koshurnikov (Dubna) December 9, 2011, GSI

The aim of an Interface document  Interface is a boundary across which two independent systems meet and act on each other  The goal of interface document is agreement about the subsystems interaction parameters and definition of subsystems envelope dimensions to let the participants to work independently Decemberr 9, 20112

3 Final decision on separation yoke/platform designs was undertaken June 2009 in Turin. For continuation of the design work Dubna team was suggested by Technical Coordinator Lars Schmitt to consider the platform surface as an absolutely rigid base.

Note: It is impossible to prepare a yoke/platform interface for the platform design with flexible beams because it can't be characterized by a limited number of coordinated parameters (for example: momentum of inertia and cross section of the vertical walls of the beams). As the interface it would take to consider platform design as a whole unit. So we would have to wait for the finalization of the platform design to include it in our FE model. Decemberr 9, 20114

5 Rigid platform beams the weight of two beams is ~22 ton

Decemberr 9, Space for cabling

Decemberr 9, Rigid platform beams: Provide stability of the yoke and it doesn’t take addition means to reinforce the yoke Liberate more space for handling with cables and target damp below the yoke footprint. Secure that the yoke rigidity is efficiently involved in general stability of the platform – there is no need in the platform cross beams.

Yoke Deformation under Torsion June 12-15, ΔY= + 1 mm ΔF = + 33 ton ΔY= + 0 mm ΔF = - 33 ton α = 0.2 mrad 1 6 1’ 6’

Two possible scenarios 9Decemberr 9, 2011

Dubna yoke/platform interface has been accepted (simultaneous activity of Dubna and Cracow groups) It takes Dubna ~0.5 year to prepare the final design of the yoke. Cracow has to change the design of the platform beams in accordance with requirements listed in our interface suggestion. Decemberr 9,

Cracow platform design with insufficient rigidity of the beams has been accepted (serial activities of both groups) It takes the final detailed design of the platform for Dubna to start this work. Dubna has to prepare a 3D FE model to evaluate the stresses in the yoke joints. After stress analysis we will be able to start coordination of new yoke frame outer sizes. At this stage we will be able to supply Cracow team with loads in the yoke support points and they have to verify their design. Having in hands their final design we could proceed to the final design of the yoke. Decemberr 9,

Possible origin of the interface problem Our Polish colleagues want to use standard I-beams in the platform design. Probably their local producer can operate with these beams only There are lots of factories in Russia, in Ukraine and (I believe) in Poland which can produce tailor designed beams 12Decemberr 9, 2011

Cryostat supports Decemberr 9, Border of responsibilities (JINR/Genoa)

Decemberr 9, List of interface problems to be fixed for finalizing the technical project of the PANDA TS Yoke 1.Attachment of the cryostat to the yoke (Coordination work is in progress) 2.It takes engineering design of the attachment units, loads on them and their geometrical characteristics for fixation to the inner surface of the yoke aperture: target production system target dump (also shape and dimensions of the recess for it in the lower barrel beam) barrel DIRC, readout system? forward EMC and disc DIRC (There is an initial suggestion from the Groningen group) backward EMC (possible interference with the door and its rails) cryogenic system on top of the magnet (chimney, control Dewar) 3.Additional equipment attached to the magnet from outside (occupied space, fixation points, masses, possible loads and acceptable deformations): on the upper barrel beam (pumps, …?) on the lower barrel beam (optical system for the target dump control, …?) at the magnet side, on the platform (boxes with electronics, …?) muon filter – possibility of door opening with the deviation of 1 О in Z direction from the plane perpendicular to the beam line, access to the units of the door halves fixation to each other is necessary 4.Final positions, shape and dimensions of recesses in the yoke for the cable passages, the detailed design of tubing and cabling is necessary

Decemberr 9, PANDA Fw Endcap EMC, status prototype KVI Groningen

Decemberr 9, THANK YOU FOR YOUR ATTENTION! СПАСИБО ЗА ВНИМАНИЕ!

Cracow platform options Decemberr 9,

The interface between platform and yoke Decemberr 9, platform – rear view (proposal Alexander Vodopyanov) The new platform – rear view

The interface Decemberr 9, platform – side view (prop. Alexander Vodopyanov) The new platform – side view

Moment of inertia for single I-beam Decemberr 9,

Geometrical Yoke/Carriage Interface 21Decemberr 9, 2011

Main Characteristics of Yoke/Carriage Interface 1.To provide further magnet vertical adjustment in the beam position, the plane of the support pads (fig.1) have to be lowered down to 5 mm from the horizontal plane Y = mm. 2.The preliminary non-flatness of the support pads plane must be secured within 0.5 mm before the yoke assembly. Additional leveling of the support surfaces will be done by means of metal shims in the process of assembly. 3.The momentum of inertia supporting beams deposited below yoke banding collars must be ≥ cm 4, 4.The cross section of the vertical wall (walls) of the beams must be ≥810 cm 2 for the overall height of the beam 790 mm. 5.The centrums of side supports of the carriage (wheels or rollers or cushions) must be at the distance ≤4930 mm (this distance corresponds to the distance between yoke frame vertical uprights). 6.During magnet relocation beam to beam inclinations in plane XY are to be α ≤ 2 х rad. 22Decemberr 9, 2011

Possible Options of the Magnet Support 23Decemberr 9, 2011

Support Beam Examples 24 N 1N 2 H, m h, m a, m b, m Jy, cm x10 6 S, cm m, ton1812 Decemberr 9, 2011

Weight loads distribution in the support points 25 1.The weight load 360 ton is distributed between 12 support pads on the carriage top. 2.The load distribution depends on the rigidity of the base and on the positions of carriage points of rest. 3.Confidence intervals of deviations from the values obtained for the magnet assembly on an absolutely rigid base are indicated in the table (in superscripts and subscripts). 4.In normal operation conditions loads are symmetric with respect to YZ-plane and approximately symmetric relative XY-plane. In abnormal regimes the symmetry can be lost but all loads remain within confidence intervals. Decemberr 9, 2011

Yoke Doors/rails Interface 1.The rails will be loaded by the door weights in assembly and beam positions only. During magnet transportation the door wheels will not interfere with the rails. 2.Maximal allowable vertical deformations of the door rail supports under action of the concentrated load of 25 ton must be ≤0.2 mm. 26Decemberr 9, 2011