LIGO Document D1001645-v1

BSC Cartridge Installation Elevation Clearance

Document #:
Document type:
D - Drawings
Other Versions:
This drawing shows the BSC Chamber Clean Room in its lowest elevation (per PSI drawing V049-4-133, Rev. 5 "BSC clean room assembly, BSC Style 1 & 3"), with the as-built LHO crane hook height (25'-9", including bridge deflection and crane vertical bounce), and an BSC cartridge assembly above the clean room ready to be lowered. The allowance for crane bridge deflection and clearance is ~8.5".
Note: The assumed that the lifting provision on the BSC-ISI assembly can fit the 2" deep hook.
The drawing "BSC clean room assembly, BSC Style 1 & 3", PSI-V049-4-133, Rev. 5 depicts the BSC Clean Room at it's maximum height. This drawing has a note that the "bottom of steel" for the 3-1/2 x 3-1/2 cross member is 12'-11-1/2" above the floor. The CAD file actually measures 13'-1/2" (156.5"), or 1" higher than noted in the drawing for the clean room in its highest position.

The drawing also has a note that the interior height of the clean room can be lowered from 16'-9" to 13'-10", or 35". Lowering the clean room then places the 3-1/2 x 3-1/2 cross member at a height of 156.5 - 35 = 121.5", or 10'-1".

The BSC cartridge assembly height is 114", from bottom of the cartridge to the center of the 2.25" diameter pin which the crane hook attaches to. The crane hook height is measured from the floor to the lower, inner opening in the hook, i.e. to the bottom of the 2.25" diameter pin. This leaves 7.4" + 2.25/2 = 8.5" clearance between the bottom of the cartridge and the top of the HEPA units on the cleanroom.

Notes and Changes:
N.B.: Drawing version -v1 shows hook height at center of mating pin, not at bottom as it should. This will be corrected in version -v2.

8/7/2010 Dennis Coyne:

Minimum static, no-load hook height = 25' 9.5"
Maximum bridge deflection under 5 ton load = 0.25"
Load oscillation with 5 ton load = ~0.25"
Therefore design for minimum hook height of 25'-9" (as shown in D1001645)

7/14/2010 Mike Meyer:

Here are the overhead crane hook heights at LLO:

Y-End - 26' 8"
X-End - 26' 2"
LVEA North - 26' 3"
LVEA East - 26' 1"
LVEA South - 26' 8"
LVEA West - 26' 5"

Our laser range finder was broken so I had to use a tape reel so there might be some error in the measurements. All of the hooks were made by Crosby and the measurement from the bottom of the hook to the inside (where I took the above measurements) was 2".

6/29/2010 Kyle Ryan:

The overhead crane hook heights at LHO:
Y-end = 26' 4 1/2",
X-end = 25' 9 1/2",
Main North-0 = 26' 5",
Main North-1 = 26' 5",
Main North-2 = 26' 5",
Main North-3 = 26' 4 1/2".
Also, I think that the Y-end hook did not stop automatically -- Ski will attempt to duplicate.

7/6/2010 John Worden:

Today we lifted our Toyota forklift (7532 pounds (5510+2022) with battery according to nameplates) with our main bridge crane in the LVEA in order to measure deflections and oscillation.

At mid span - assumed worst case:

Measurement of bridge deflection was measured with a HILTI PD30 laser range meter.
Loaded - distance = 28' 6 3/8 inch
Unloaded = 28' 6 9/16

Therefore deflection due to 7500 pound load ~ 3/16 inch - Expect that with 10,000 load the deflection will be 1/4 inch worst case.
Also - we looked at vertical oscillation of the load after stopping of the hoist = we measured with a tape measure and estimate 1/8 inch to 1/16 peak to peak in vertical.

The above measurements were repeated several times, as well we checked again with the load positioned at a different span and found lesser deflection but similar oscillation.

Referenced by:
Associated with Events:
held on 22 Sep 2010

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