Doc #: 2100-AD Revision: - Removal of FFT Spectrograph Support Pedestals and 500 lb Crane from 4m Coude Room.

Transcription

1 Doc #: 2100-AD Revision: - Removal of FFT Spectrograph Support Pedestals and 500 lb Crane from 4m Coude Room Author(s): mevatt

2 1. Contents Revision History Purpose Applicable To Scope Definitions Training Safety Personnel, Equipment and Materials Required Procedure South Pedestal Point A Procedure Review Records References AD Docx Page 2 of 16

3 Revision History Rev Date Approved Sections Affected Reason for Change Remarks and/or Change Details - 11/14/2016 Initiated Evatt Name Approved by: SigEng Name, ME Title SigEM Name, EL Maint SigSci Name, SciOps Tammie Lavoie 17 February 2017 Tammie Lavoie, Safety Manager Date 2100-AD Docx Page 3 of 16

4 1. Purpose The purpose of this document is to specify how the two pedestals originally installed to support the FFT Spectrograph Bench in the 4m Coudé room are to be removed. This document also includes instruction about how to remove the 500 lbf crane currently sitting on the Northern pedestal. 2. Applicable To 4m, DESI 3. Scope This document covers the removal of pedestals in 4m Coudé room, removal of 500 lbf crane from northernmost pedestal, and the installation of cover plates over the holes left in the floor. 4. Definitions LCR Large Coudé Room 5. Training Personnel performing this task will variously need to be proficient in: 1. Operating a forklift 2. Using a cutting torch 3. Using standard hand and power tools 6. Safety 1. JHA Form 2. Daily Briefing Form 7. Personnel, Equipment and Materials Required 1. Personnel: This task will take three people dedicated to the job to perform safely, and a four person during some parts of the process (lifting the crane, lifting the pedestals). 2. Equipment: 2.1. Forklift 2.2. Cutting torch EA x 4 foot lifting slings, shackles, and other rigging supplies capable of lifting about 1500 lbs 2100-AD Docx Page 4 of 16

5 EA 1-8 lifting eyes (such as McMaster Carr part number 3013T55 Steel Eyebolt without Shoulder, 1-8 Thread Size, 2-1/2 Thread Length) EA heavy tag lines to control the pedestals as they are cut off and lifted out of their holes in the floor Various standard hand tools including sockets, drives, and wrenches An acetylene torch with gas bottles An arc welding machine set up to weld carbon steel A few 4 x 4 wood pieces to set the crane and the pedestals on as they are removed. 3. Materials 3.1. Precut steel plates for use in covering the holes that will be left when the pedestals have been removed. 8. Procedure South Pedestal Point A Background and Summary There are two steel pedestals located in the Mayall Large Coudé Room (LCR). One of the pedestals is at the south end of the LCR and the other is at the north end of the LCR. The north pedestal has a 500 lbf jib crane mounted on it. On drawing 2100-SOM5947-S-E-19, the south pedestal is called Point A and the north pedestal is called Point B. Refer to Figure 1 to see this naming convention. These two steel pedestals need to be removed from the LCR in order to make room for the DESI Spectrograph Enclosure, to allow more access to certain areas of the room, and to allow more room for maneuvering equipment including the spectrographs themselves into the room. Removal of the pedestals will require that they be torched off below the Main Floor level, and then lifted out from above. The reason for this is that the pedestal bases are much larger than the 3-6 [42 ] x 3-6 [42 ] clear openings constructed around them in the main floor (Figure 2, Figure 3 and Figure 4) AD Docx Page 5 of 16

6 Figure 1. LCR Floor Framing Plan Showing Points A (South) and B (North) Figure 2. Openings in Floor 42 x 42 (Reference Drawing 2100-SOM5947-S-E-9) 2100-AD Docx Page 6 of 16

7 Figure 3. Point A (South) Pedestal Base D1 (48 x 84 ) Figure 4. Point 'B' (North) Pedestal Base D2 (42" x 72") 2100-AD Docx Page 7 of 16

8 Additionally, before removing the Point B north pedestal, the 500 lbf capacity jib crane currently bolted to the top of the pedestal (Figure 5) will have to be removed. Removal of the crane will be detailed in the procedure below. Figure 5. Jib Crane on North Pedestal 2100-AD Docx Page 8 of 16

9 8.1 Procedure for Removal of South Pedestal An elevation view of the south pedestal is shown in Figure 6. To get the pedestal out, we will cut it off below the level of the floor just low enough to allow the installation of a steel cover plate over the hole in the floor. Figure 6. Elevation Views of South Pedestal 1. The portion of the pedestal that will be removed (if it is cut about 10 inches below the floor surface) should weigh about 1000 lbs (Calculated from an incomplete SolidWorks model). 2. Remove the rubber seal and flashing from the floor that surrounds the pedestal. 3. Lower the cutting torch through the Coudé room floor through one of the existing floor penetrations in the Coudé room. 4. Lower the arc welding electrode holder, ground clamp, and leads through the Coudé room floor through one of the existing floor penetrations in the Coudé room. 5. Open the dome floor hatch, referring to procedure 2100-AD Remove at least the center section; measure the forklift that will be used to determine if more need to be removed (JHA-2). 6. Bring a forklift capable of lifting 1500 lbs up from the ground floor onto the main floor and drive it into the LCR to lift the pedestal (JHA-3). Note: If one of the instrument lifts in the Coudé room can be used for this instead of a forklift, that would be acceptable. Check the capacity and stability of any equipment that will be used AD Docx Page 9 of 16

10 7. Drill and tap one ½-13UNC holes through on each side of the pedestal as shown in Figure 7. The hole locations should be about 18 inches directly above the CG of the pedestal after it has been cut off in the location shown. Figure 7. South Pedestal with Floor Level and Lifting Lug Bolt Hole Locations Shown 8. Bolt on the McMaster Carr 2994T42 Pivot Hoist Rings (2500 lbs capacity each) as shown in Figure 8. Use a 3/8 inch hex wrench AD Docx Page 10 of 16

11 Figure 8. Pivot Hoist Ring Installed on South Pedestal 9. Connect two 4 ft lifting straps to the lifting eyes using shackles. 10. Loop both lifting straps over a forklift arm. 11. Tie the two taglines to the pedestal just above the floor on opposite sides of the pedestal. 12. Lift with the forklift until the weight seems to be taken by the forklift (JHA 4). 13. Go below the Coudé room floor into the hammer head and torch cut the pedestal off just below the floor (JHA 5), using the taglines to control the load as it is lifted. 14. Lift the pedestal out of the hole with the forklift, and then take it over where the dome crane can pick it up (JHA 6). 15. Lift the pedestal with the dome crane (5 ton) and move it down to the ground floor onto some waiting 4 x 4 lengths of wood or onto a truck (JHA 7) AD Docx Page 11 of 16

12 16. Install the steel floor plate cover over the hole. Weld the plate into place (JHA 8) as required. Removal of the South Point A Pedestal is now complete. 8.2 Procedure for Removal of North Point B Pedestal An elevation view of the North Pedestal is shown in Figure 10. Similarly to the South Pedestal, to get this pedestal out, it will be cut off below the level of the floor, pulled out, then a steel cover plate will be installed in the floor to cover the hole. The North Pedestal has the added complication of supporting a crane which we will have to move before we can cut the pedestal off to remove it. Figure 9. Crane Dimensions and Weight 2100-AD Docx Page 12 of 16

13 Figure 10. Point 'B' North Pedestal 1. Prepare a place to lay the crane down once it has been removed. 2. Remove the rubber seal and flashing located around the pedestal hole in the floor. 3. Terminate electrical power and remove all conduit, junction boxes, crane hoist assembly, and droplight from arm. 4. Using SKY LIFT scissor lift, position lift perpendicular under center of arm ( I beam) and raise to where the side rails of scissor lift just supports the arm (JHA 9). 5. Remove the six ¾-10 bolts that attach the arm to pedestal and slowly raise arm off pedestal mount. 6. Secure arm and reposition scissor lift as needed and lower with arm secured to side rails. 7. With the lift in the down position the I beam can now be manually transferred off the scissor lift AD Docx Page 13 of 16

14 8. Drill and tap one hole on either side of the pedestal in the approximate location shown in Figure 11. These holes should be about 14 inches directly above the center of mass of the pedestal after it has been cut off at the location shown in Figure 11. Figure 11. North Pedestal B after Crane Has Been Removed 9. Bolt the same hoist rings used for the previous pedestal, McMaster Carr part number 2994T42, to the newly drilled and tapped holes as shown in Figure AD Docx Page 14 of 16

15 Figure 12. North Point B Pedestal Cutoff Location 10. Connect a lifting strap to each hoist ring via a shackle and secure each strap to one of the forklift forks. Lift up with the forks until the weight is taken by the forklift (JHA 10). 11. Tie the two taglines to the pedestal just above the floor on opposite sides of the pedestal. 12. Using a torch, cut the pedestal off about 10 inches below the floor (see Figure 12). Use the two taglines to control the load as it is cut off from its base. See Figure 13 for a view of what the Northern Pedestal looks like from in the hammer head (JHA 11) AD Docx Page 15 of 16

16 Figure 13. Picture of Bottom of North Pedestal 13. Lift the pedestal out of the hole in the floor (JHA 12) and move it using the taglines to control the load (JHA 12) to a location where it can be picked up by the crane and lowered through the hatch to the ground floor (JHA 13). 14. Install a pre-made steel plate over the opening as was done with the cover plate over the South Pedestal floor hole (JHA 14). 9. Procedure Review None 10. Records 1. JHA signature sheet; kept by safety office, scanned and stored \ets_share\safety 2. Fall protection training: kept by Safety Office 3. Rigging, suspended load: kept by Safety office 11. References DOCUMENT NUMBER NA D D SOM5947-S-E SOM5947-S-E-19 DOCUMENT TITLE KPNO Emergency Manual Point A Pedestal Detail (South Pedestal) Point B Pedestal Detail (North Pedestal) Main Floor Framing Plan Optional Hammerhead Framing Plan 2100-AD Docx Page 16 of 16