SBS Magnet and Support Status

Robin Wines

Magnet Status•48D48 Dipole Magnet from BNL•BNL has 4 in storage•BNL agrees to disassemble and ship to Jlab

•Visiting BNL to discuss assembly procedure and details of magnet fabrication

SBS Magnet ParametersSBS Magnet Parameters

Dipole Field Orientation horizontal, Bx

Maximum Field 1.69T

Integral Field Strength 2.0 T-m, 2.5 T-m with pole shims

Yoke Length 1.22m

Gap 46.99cm x 121.92cm

Weight Yoke 84.7tons

7 1008 steel sectors, largest = 18.3 tons

Number of turns per pole1 coil per pole, 120 turns per coil

Length of conductor 1693 m

Weight of coil 5.2 ton per coil

Dimensions of conductor 2.18cm square, 1.27cm dia hole

Current 2000A

Resistance 0.110 ohm

Voltage 220V

Power 440KW

Water flow 150psi,100gpm

Temperature rise 17C

48D48 Magnet Modifications

•2 yoke sectors machined for beam line slot•New saddle coils with ends sized to clear beam pipe butBeam pipe location changes in different configurationsSaddle coils make it difficult to move or change out the beam pipe

Magnet Modifications Revised

•Use one existing saddle coil•2 new racetrack coils•Racetrack coils allow ease of beam pipe access and aid in shielding•Additional Machining on corners to clear BigBite configurations

To-do•Analyze stray fields and shielding requirements•Complete design of new coils•Detail yoke modifications•Assembly procedure

SBS Kinematics

SBS Configurations•Iterations of design layout and Kinematics of all Experiments to alleviate interferences such as: magnet to magnet, utility supports, field clamps, location of beam line and gate valve, BigBite shielding, HRS support links

•SBS at distances from target of 1.6 meters to 3.0 meters•BigBite at distance of 1.5 meters from target•Angles require close proximity of SBS and BigBite

•At pivot, support to floor limited by HRS support links•GMn kinematics define limits for supporting SBS magnet

SBS GMn Q2 =6.0Location of SBS magnet limits support to floor over pivot link

SBS GMn Q2= 10.0

Close proximity of SBS and BB requires modifications to SBS and shielding consideration

SBS GMn Q2= 13.5Increase slot size to clear beam pipe

SBS Magnet Support

Design concept based on use of 2nd 48D48 magnet yoke pieces used as counterweight base –total 150 tons

4 Hilman Swivel Rollers to move and position magnet- total load of 330 tons

Magnet fixed on ledge of base

SBS Magnet Positioning

Summary

To meet Program Milestones, SBS Magnet and Support designs need to be finalized and detailed by March 2013

Ask collaboration to review Kinematics and provide details of detector requirements (support points, weights, size, lifting…….)