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Entry  Fri May 4 18:59:39 2018, gautam, Update, SUS, Stack measurement ongoing 
    Reply  Mon May 7 15:27:28 2018, gautam, Update, SUS, Stack measurement expectation 40m_TMstack.JPG
Message ID: 13821     Entry time: Mon May 7 15:27:28 2018     In reply to: 13815
Author: gautam 
Type: Update 
Category: SUS 
Subject: Stack measurement expectation 


We tried to estimate what the load cell measurement should yield. Here is the weight breakdown (fudge factor for Al table is to try and account for tapped holes):


Diameter [m]

Height [m]

Density [kg/m^3]

Mass [kg]

Number or fudge factor

Dim in inches

Table 1.22 0.08 2700.00 240.07 0.85 Dia=48", thickness=3"
Stack leg 0.36 0.13 8000.00 100.85 9 Dia=14", thickness=5"
Base plate 1.37 0.05 8000.00 600.18 1 Dia=60",thickness=2"
Base rods 0.10 1.83 8000.00 118.55 2 Dia=4", length=6ft
Stuff on table       100.00    
Blue beams       100.00    
Total [kg]       2149.01    
Total [lbs]       4835.28  


  • Steve pointed out that there is some material removed from the stack legs for stability (hollows into which the viton springs fit). These countersinks have dimensions of diameter=2", height=1.75". So if we assume each leg has 10% less mass, the total weight becomes ~4600lbs.
  • I think we will need to use one more load cell (i.e. total 4) for this measurement (we have more load cells, just need to setup one more controller).
  • Steve is looking into acquiring some low profile jacks to deal with the fact that we only have limited travel range on the overall stack height because of the bellows.
  • A useful document, from which we pulled some numbers (which also look reasonable using estimated dimensions and density calculations): P952005
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