+-----------------------------------------------------------------------+
| ####### ![                                                            |
| ](media/image1.jpeg){width="0.84375in" height="0.8645833333333334in"} |
|                                                                       |
| ####### DFBX -- D1 (LBX) Interconnect Procedure                       |
+-----------------------------------------------------------------------+
| **Reference Drawings:**                                               |
+-----------------------------------------------------------------------+
| **Interconnection D1 to DFBX Assembly**                               |
|                                                                       |
| **(14130017)**                                                        |
+-----------------------------------------------------------------------+
| **DFBX -- LBX Interface Specification**                               |
|                                                                       |
| **(LHC-DFBX-ES-0230)**                                                |
+-----------------------------------------------------------------------+
| **DFBX Connections to D1**                                            |
|                                                                       |
| **(24C3236, IR2L & IR8L)**                                            |
|                                                                       |
| **(24C3246, IR2R & IR8R)**                                            |
+-----------------------------------------------------------------------+
| **Note: This procedure is based on BNL document SMD-LHC-3001.**       |
+-----------------------------------------------------------------------+
| **By: Jamie Blowers, Phil Pfund**                                     |
|                                                                       |
| **Technical Division, Fermilab**                                      |
+-----------------------------------------------------------------------+

+---+---------------------------------+----+--------+----+---+------+
| * | **Description**                 | *  | **Nu   | *  | * | **   |
| * |                                 | *D | mber** | *R | * | Quan |
|   |                                 | wg |        | ev | U | tity |
| * |                                 | Si |        | ** | n | Re   |
| * |                                 | ze |        |    | i | quir |
|   |                                 | ** |        |    | t | ed** |
|   |                                 |    |        |    | * |      |
|   |                                 |    |        |    | * |      |
+---+---------------------------------+----+--------+----+---+------+
| - | Dipole magnet assembly (D1)     |    | 14     |    |   | 1    |
|   | Tested                          |    | 060005 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 3 | Vacuum Vessel Bellows (24 inch) |    | 14     |    |   | 1    |
| . |                                 |    | 130001 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 4 | Cap, Xb line                    |    | 14     |    |   | 1    |
| . |                                 |    | 130019 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 5 | Instrumentation Board           |    | 14     |    |   | 1    |
| . |                                 |    | 130016 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 6 | M/C line bellows                |    | 14     |    |   | 1    |
| . |                                 |    | 130024 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 7 | Cap, CYt 1.9k transfer line     |    | 14     |    |   | 1    |
| . |                                 |    | 130022 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 8 | Upper heat shield               |    | 14     |    |   | 1    |
| . |                                 |    | 130011 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
| [ |                                 |    |        |    |   |      |
| ] |                                 |    |        |    |   |      |
| { |                                 |    |        |    |   |      |
| . |                                 |    |        |    |   |      |
| m |                                 |    |        |    |   |      |
| a |                                 |    |        |    |   |      |
| r |                                 |    |        |    |   |      |
| k |                                 |    |        |    |   |      |
| } |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 9 | Lower heat shield               |    | 14     |    |   | 1    |
| . |                                 |    | 130015 |    |   |      |
|   |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
| [ |                                 |    |        |    |   |      |
| ] |                                 |    |        |    |   |      |
| { |                                 |    |        |    |   |      |
| . |                                 |    |        |    |   |      |
| m |                                 |    |        |    |   |      |
| a |                                 |    |        |    |   |      |
| r |                                 |    |        |    |   |      |
| k |                                 |    |        |    |   |      |
| } |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | Instrumentation sleeve          |    | 14     |    |   | 1    |
| 0 |                                 |    | 130018 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
| [ |                                 |    |        |    |   |      |
| ] |                                 |    |        |    |   |      |
| { |                                 |    |        |    |   |      |
| . |                                 |    |        |    |   |      |
| m |                                 |    |        |    |   |      |
| a |                                 |    |        |    |   |      |
| r |                                 |    |        |    |   |      |
| k |                                 |    |        |    |   |      |
| } |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | Splice bar, two holes           |    | 12130  |    |   | 2    |
| 1 |                                 |    | 080-05 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | Fiberglass tape                 |    | 12     |    |   | As   |
| 2 |                                 |    | 010135 |    |   | req. |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | MLI blanket assy, inner pipes   |    | 14     |    |   | 1    |
| 3 |                                 |    | 130007 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | MIL blanket assy, outer pipes   |    | 14     |    |   | 1    |
| 4 |                                 |    | 130008 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | MLI blanket assy, heat shield   |    | 14130  |    |   | 1    |
| 5 |                                 |    | 010-01 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | MLI blanket assy, heat shield   |    | 14130  |    |   | 1    |
| 6 |                                 |    | 010-02 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | Rivet                           |    | MS24   |    |   | 4    |
| 7 |                                 |    | 630-73 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | ¼-28 tapping pan screw          |    | MS24   |    |   | 46   |
| 8 |                                 |    | 630-73 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 1 | Solder (paste)                  |    | 12     |    |   | A/R  |
| 9 |                                 |    | 010069 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Solder (ribbon)                 |    | 12020  |    |   | A/R  |
| 0 |                                 |    | 421-03 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Polyamide insulation film       |    | 12010  |    |   | A/R  |
| 1 |                                 |    | 181-20 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Persistent ring, CY & CYt lines |    | 14     |    |   | 1    |
| 2 |                                 |    | 130027 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Persistent ring, E1 line        |    | 14     |    |   | 1    |
| 3 |                                 |    | 130028 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
|   | Persistent ring, E2 line        | MB | 432021 |    |   | 1    |
+---+---------------------------------+----+--------+----+---+------+
|   | Transition piece, E2 line       | MB | 432022 |    |   | 1    |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Persistent ring, XB & XBt lines |    | 14130  |    |   | 1    |
| 4 |                                 |    | 029-01 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Filler bar                      |    | 14     |    |   | 2    |
| 5 |                                 |    | 130031 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Persistent ring, C line         |    | 14     |    |   | 1    |
| 6 |                                 |    | 130025 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Persistent ring, C' line        |    | 14     |    |   | 1    |
| 7 |                                 |    | 130026 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Channel insulator               |    | 12130  |    |   | 2    |
| 8 |                                 |    | 013-01 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 2 | Channel insulator               |    | 12130  |    |   | 1    |
| 9 |                                 |    | 013-02 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 3 | Solder (round wire)             |    | 12010  |    |   | 1    |
| 0 |                                 |    | 070-01 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 3 | Persistent ring, XB & XBt lines |    | 14130  |    |   | 1    |
| 2 |                                 |    | 029-02 |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
| 3 | Kevlar string                   | MA | 369912 |    |   | A/\$ |
| 3 |                                 |    |        |    |   |      |
| . |                                 |    |        |    |   |      |
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
|   | O-ring (CERN-supplied)          |    |        |    |   | 1    |
+---+---------------------------------+----+--------+----+---+------+
|   | **Tooling**                     |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
|   | Bus splice fixture              | MC | 430189 |    |   |      |
+---+---------------------------------+----+--------+----+---+------+
|   |                                 |    |        |    |   |      |
+---+---------------------------------+----+--------+----+---+------+

**[GENERAL NOTES:]{.mark}**

-   [All screws installed in the vacuum and cryogenic space must have
    some form of additional protection from working themselves loose
    during thermal cycling. The use of Loctite 242 or 245, or Stycast is
    recommended for this purpose.]{.mark}

[]{.mark}

**(Complete Above Ground)**

1.  Bolts and washers from the vacuum vessel end can need to be retained
    and re-installed at the end of this procedure.

2.  Fabricate the M/C line bellows assembly. This should include
    shortening the cuff of the M/C line bellows by 10mm, and then
    welding the adapter (no part number) to the M/C line bellows
    (14130024).

3.  Add the appropriate features to the M/C line bellows, as per the
    CERN-defined drawing(s).

4.  Install and weld the transition piece (MB-432022) to the e2 line on
    the D1 magnet.

5.  Cut the heat shield assembly (upper 14130011, lower 14130015) from
    853 to 800 mm. Part 14130011 can be shortened by removing 53 mm from
    the non-featured end. Part 14130015 can be shortened by removing
    53mm from the D1 end, and then redrilling the holes according to
    drawing 14130012.

6.  Fabricate the large Multi-Layer Insulation (MLI) inner and outer
    blankets that wrap over the pipe group (14130007 & 14130008, items
    13 & 14 on parts list) on a suitable table prior to their need. They
    are not provided in the interconnect parts kit. However, drawings
    for their fabrication are provided. These blankets extend for the
    length of the interconnect.

7.  Fabricate the large Multi-Layer Insulation (MLI) inner and outer
    blankets for the heat shield (14130010-01 & 14130010-02, items 15 &
    16 on parts list) on a suitable table prior to their need. They are
    not provided in the interconnect parts kit. However, drawings for
    their fabrication are provided. NOTE: these blankets may need to be
    adjusted in length in step 17.

8.  Install the CERN-supplied Beam Screen assemblies per the CERN
    drawings listed below.

##### CERN Drawings

-   Beam Vacuum Interconnects Assembly Type IT 7 IR Right (LHCLVIKK0002)

-   Beam Vacuum Interconnects Assembly Type IT 8 IR Right (LHCLVIKK0003)

-   Beam Vacuum Interconnects Assembly Type IT 7 IR Left (LHCLVIKK0004)

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-   Beam Vacuum Interconnects Assembly Type IT 8 IR Left (LHCLVIKK0005)

9.  Caps for XB/XBt and CY/CYt could be installed and welded above
    ground or below ground (steps 18 and 19 of this procedure).

> NOTES:
>
> \(1\) Connection or capping of the XB & XBt lines is dependent on the
> magnet's installation location. Refer to Section G-G and Section C-C,
> Sheet 2 of drawing 14130017.
>
> \(2\) Section C-C of drawing 14130017 for IR2L & IR8L should call out
> use of Item 32, [not Item 24.]{.underline}

**(Complete before setting units into position)**

10. Insert the large O-ring (CERN-supplied) into the groove on the
    sliding flange. Detach and slide back the sliding flange on the
    vacuum vessel. Install the large vacuum vessel bellows (14130001)
    over the end of the D1 magnet and store there until the
    interconnection work is nearly complete. Take precautions to avoid
    internal and external damage to the convolutions.

11. Install the M/C line bellows assembly (modified 14130024) over the
    roll-back flange on MBX1 line of the DFBX. Slide the bellows back
    and store over the tube to provide access to the bus interconnect
    region.

12. Install the instrumentation sleeve (14130018), over the MBX2 line on
    the DFBX, and slide back for storage.

13. XB/XBt lines preparation.

> NOTES:
>
> \(1\) Connection or capping of the XB & XBt lines is dependent on the
> magnet's installation location. Refer to Section G-G and Section C-C,
> Sheet 2 of drawing 14130017.
>
> \(2\) Section C-C of drawing 14130017 for IR2L & IR8L should call out
> use of Item 32, [not Item 24.]{.underline}

1.  Install the persistent rings (14130029-01 or 14130029-02 as
    appropriate), on the correct pipes. DO NOT weld.

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14. C line preparation.

> NOTE: Refer to Section J-J on Sheet 2 of drawing 14130017.

1.  Install the persistent rings (14130025), on the C pipe. DO NOT weld.

**(Complete Below Ground)**

15. M/C (bus) line splices.

> NOTE: When warm, the D1 lines will be nominally 1.7mm higher than the
> mating lines on the DFBX. These will line up upon cool-down.
>
> NOTE: The bus bars on the D1 magnet extend out from the M/C line. They
> are labeled "A" and "B" to indicate polarity in order to produce the
> desired field direction. Positive current flowing into bus bar "A"
> produces a positive (upward) dipole field.

1.  Pre-tin all leads to be spliced with solder made of 96% tin/4%
    silver.

2.  Refer to Detail K on Sheet 3 of assembly drawing 14130017. Form the
    magnet and DFBX superconductor cables as shown, placing the DFBX
    superconductor on the outside. It may be necessary to trim and dress
    the leads to achieve the 127 mm splice overlap. Place flux and
    silver/tin solder ribbon (flattened round wire solder) between the
    two cables that make up the "A" cable pair, and a second ribbon
    between the two cables that make up the "B" cable pair.

3.  Similarly, form the copper stabilizer ends from the DFBX over the
    superconductors as shown. Install flux and solder ribbons under the
    "A" and "B" legs of stabilizer cable.

4.  Install the 2-hole splice bars (12130080-05) onto the end of the D1
    bus. Solder to the bus (the rivets do not get peened over, but are
    held by the solder only). Allow to cool.

5.  Place flux and solder ribbon on the inside surface of each solid
    stabilizer (between it and the DFBX stabilizer cable).

6.  Insert the bus splice assembly into the soldering fixture
    (MC-430189). Screw the top of the fixture around the splice area.

7.  [If desired, add an additional temperature measuring device (e.g.
    handheld thermocouple).]{.mark}

8.  Turn on resistive heaters, and wait for the solder to melt, while
    monitoring the temperature. [Tighten screws as the solder is
    softening, so that the fixture is completely closed when the solder
    is completely melted.]{.mark} When the solder has melted, turn off
    the heater [controller]{.mark}. The solder typically melts at about
    220° C, but the [temperature should be held at 235°C for one
    minute]{.mark}. Do not allow the temperature to exceed 240°C.

9.  Monitor the temperature during cool-down, and [let splice cool to \~
    40°C. To monitor the temperature, unplug the heating element, and
    then turn the controller back on]{.mark}.

10. After cooling [(to \~ 40°C)]{.mark}, remove the splices from the
    fixture. **[NOTE: It is easiest to remove the splices while the
    fixture is a little warm, so it is best not to let it cool to room
    temperature before removing the leads from the fixture.]{.mark}**

11. Clean exterior of splices with Tech spray and Scotch Brite or
    equivalent. Wipe down with Kay-dry or equivalent. Check especially
    the areas beyond the actual joint area for possible "wicking" of
    flux.

12. Perform electrical check for proper isolation of bus bar "A" from
    bus bar "B".

13. Install two Nomex insulator channels (12130013-01) in the open joint
    area between bus bar "A" and bus bar "B". Butt together these two
    pieces at the approximate center of the soldered joint and apply
    Kapton tape to maintain alignment of the channels and prevent the
    butt joint from overlapping.

14. Install the single Nomex insulator channel (12130013-02) over the
    previous two channels. Center this channel over the butt joint
    between the other two channels.

15. Visually inspect the partially insulated joint for any possible
    voltage creep problems.

16. Wrap the entire joint using Kapton tape and fiberglass tape, 50%
    overlap for each material. The tapes should extend for the entire
    length as dimensioned in Detail K on sheet 3 of assembly drawing
    14130017, starting on the G-10 conduit of the D1 bus and enclosing
    the wrap on the DFBX bus.

17. [Wrap entire splice bundle with Kevlar string (MA-369912, or
    equivalent) in a similar fashion to cartoon below (figure 15.17-A).
    The spacing between each loop should be \~ 1.5 cm, and the string
    should be pulled tightly around the splice bundle. Apply Loctite to
    each cross-over to hold the string in place. The colors of the
    string in the cartoon below (figure 15.17-A) show the way in which
    the string is wrapped, but the string should be one continuous
    piece, as much as is possible.]{.mark}

**[[Figure 15.17-A]{.underline}]{.mark}**

18. Perform electrical check of completed bus to CERN procedures.

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16. i (instrumentation) splices.

> NOTE: The instrumentation wiring is located within the D1 i stub,
> which extends from the end volume face. Refer to Section F-F on sheet
> 2 of drawing 14130017 for details of the instrumentation connection.

1.  Position the instrumentation board (14130016) within the open area
    between D1 and the DFBX. The board will eventually be captured
    inside the instrumentation sleeve, but during wiring it will need to
    be supported externally.

2.  Referring to the pin connection callouts on the schematic (Section
    F-F on page 3 of 14130017, or drawing 14130016. Note number 4 of
    drawing 14130017 refers to part '31', which does not exist in the
    parts list), route the labeled leads to be connected between D1 and
    the DFBX to the correct pin number in the instrumentation board. A
    suggested wire routing method is shown in Section F-F, but actual
    practice may dictate other routing alternatives.

3.  Solder each connection using silver/tin round wire solder.

> NOTE: For installation of magnet D1L105 in IR8R only, a temperature
> sensor must be installed on the instrumentation board as a replacement
> for the failed yoke-temperature sensor (Waiver M0272). Holes have been
> provided on all four boards for this particular installation. The
> sensor to be installed is to be a calibrated CERNOX sensor
> manufactured by Lake Shore, Westerville, Ohio, USA. It is not provided
> in the parts kit.

4.  Secure wires to board at tie points indicated using Kevlar cord
    (CERN-supplied). Secure knot using epoxy (CERN-supplied).

5.  Perform electrical tests to CERN procedures after all connections
    are complete.

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17. M/C (bus) line welding.

    1.  Using the CERN-supplied tooling, compress the M/C line bellows
        20 mm. Slide the M/C line bellows back over the completed bus
        joint. Align the end cuffs of the bellows with the flanges.
        Further extension or compression of the bellows (±3 mm) is
        acceptable if required to provide a weldable edge joint.

    2.  Tack weld the bellows to the flanges. Complete the welding to
        produce a leak-tight joint per section A-A, sheet 1, of print
        14130017.

18. i (instrumentation) line welding.

    1.  Slide the instrumentation sleeve over the completed
        interconnect. Tack weld the sleeve to the flanges, then complete
        the weld per Section F-F, sheet 2 of 3, of drawing 14130017.

    2.  Perform electrical tests to CERN procedures again after welding
        is complete.

19. CY & CYt line preparation

> NOTE: Connection or capping of the CY & CYt lines is dependent on the
> magnet's installation location. Refer to Section A-A and Section E-E,
> Sheet 2 of drawing 14130017.

1.  Install the cap (14130022) and persistent ring (14130027) on the
    correct pipes. Complete ONLY the weld of the cap. DO NOT weld the
    persistent ring.

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20. XB & XBt line preparation

> NOTES:
>
> \(1\) Connection or capping of the XB & XBt lines is dependent on the
> magnet's installation location. Refer to Section G-G and Section C-C,
> Sheet 2 of drawing 14130017.
>
> \(2\) Section C-C of drawing 14130017 for IR2L & IR8L should call out
> use of Item 32, [not Item 24.]{.underline}

1.  Install the cap (14130019) on the correct pipe. Complete ONLY the
    weld of the cap.

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21. C' line preparation

> NOTE: Refer to Section J-J and Section I-I, Sheet 2 of drawing
> 14130017.

1.  Install the persistent ring (14130026), on the C' pipe,
    respectively, but DO NOT weld.

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22. Cold mass pipe connections and welding

    1.  Locate the pipes on the DFBX that connect to the respective
        pipes on the D1 magnet. Slide the ends of the pipes over the
        persistent rings on the mating pipes. The CY/CYt, XB/XBt and
        C/C' pipes should now be physically connected to the DFBX.

    2.  Weld the CY/CYt, XB/XBt and C/C' pipes by consuming the ridge on
        each persistent ring as per Sections A-A/E-E, G-G/C-C and
        J-J/I-I of drawing 14130017. The C/C' and XB/XBt pipes will most
        likely NOT be weldable using automatic equipment due to their
        proximity to adjacent pipes, so manual welding will need to be
        used.

    3.  Pressurize and leak check the cold mass piping to CERN procedure
        after welding.

23. D1 collection pot temperature sensor connections.

> NOTE: There are four four-wire RTD bundles coming out of the DFBX.
> Only two bundles are used at any single tunnel location (i.e. two
> locations connect to the D1 using PS1 and PS2, and the other two
> locations connect to PS3 and PS4).

1.  Using the appropriate configurations, as defined in the schematics
    listed below, solder the appropriate D1 phase separator temperature
    sensor wires to the matching wires from the DFBX.

> [Location]{.underline} [LBNL drawing]{.underline} [(CERN drawing
> number)]{.underline}
>
> IR2L 25I6156 LHCDFBX_0032
>
> IR2R 25I6166 LHCDFBX_0033
>
> IR8L 25I6196 LHCDFBX_0036
>
> IR8R 25I6206 LHCDFBX_0037

24. Heat shield pipe preparation, connection and welding

> NOTE: Refer to Section D-D and Section H-H, Sheet 2 of drawing
> 14130017, for the e1 and e2 pipes. The e2 line uses a different
> persistent ring than is identified on the drawing.

1.  Install the persistent ring (14130028) on the e1 pipe, but DO NOT
    weld.

2.  Install the persistent ring (MB-432021) on the e2 line, but DO NOT
    weld.

3.  Join the mating piping from the DFBX to the e1 and e2 pipes. Weld
    the pipes by consuming the ridge on each persistent ring, as per
    Sections H-H and D-D of drawing 14130017.

4.  Pressurize and leak check the heat shield piping after welding.

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25. Insulating connected pipes

> NOTE: The M/C, i, CY , and CYt lines must be individually insulated
> across the interconnect region.

1.  For one of the four pipes listed above, fabricate four 8-layer
    blankets that will wrap around the uninsulated length of the pipe
    (these blanket assemblies are not defined in a drawing, nor are they
    called out in drawing 14130017). Consider the largest diameter to be
    encircled (e.g., over bellows). The outer blankets need to encompass
    the inner ones, but the blankets do not need to fit tightly on the
    pipes and can be "bunched" a bit.

2.  Wrap one blanket around the pipe. Butt together the seam where the
    blanket edges join and apply aluminum tape to hold in place. Install
    the second 8-layer blanket so that its seam is 90º from the first.

3.  Install the second, third and fourth 8-layer blankets in the same
    way, taping the seam. The seams should always be 90º away from the
    previous layer.

4.  Repeat the previous three steps for each of the other three pipes to
    be insulated.

5.  Install the pipe blankets around the entire group of pipes as shown
    on the drawing. Locate the joints near the bottom to reduce strain
    on the joints, but stagger the joints. The seam may be overlapped
    rather than butted for strength and ease of installation. Secure the
    joints with aluminum tape.

> NOTE: To install the blankets around the top of the cold mass (under
> the heat shield), the heat shield will need to be temporarily
> compressed laterally in order to create enough room vertically to
> slide the blankets under the shield. A large hydraulic c-clamp or
> other suitable means will be needed to do this. Do not permanently
> distort the shape of the heat shield.

26. Heat Shield Installation

> NOTE: The upper and lower heat shield interconnect sections fit over
> and attach to the shield of the D1 magnet. Refer to Section A-A, sheet
> 1, of drawing 14130017.

1.  Install the lower shield section first. Make a "dry fit-up" to
    determine that the part fits properly. Correct any problem areas
    now.

2.  The lower (and upper) interconnect shield is cooled via conduction
    to the shield in D1. To enhance thermal contact between the two
    parts, apply a layer of Apiezon N to the overlapping surfaces before
    they are mechanically fastened.

3.  Make the final installation by driving the self-tapping screws
    through the interconnect shield into the D1 shield at the holes
    provided. Make certain there is good thermal contact between the two
    parts. [Be sure to apply Loctite (or equivalent) to all
    screws.]{.mark}

4.  Repeat the previous three steps for the upper shield section
    [(again, be sure to apply Loctite, or equivalent, to all
    screws)]{.mark}. Make sure that no thermal insulation inside the
    shield sections will be resting on or close to the longitudinal
    joint, since this joint must be welded together. If inside contact
    cannot be prevented, a ceramic blanket (CERN-supplied) will need to
    be installed at the troublesome locations, such blanket(s) remaining
    inside the interconnect.

5.  Weld the longitudinal joint between the upper and lower parts per
    drawing 14130017. Intermittent weld joint is acceptable.

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27. Insulating the Heat Shield

    1.  Check the axial length between the blankets on the D1 and the
        DFBX to which the interconnect blankets will mate, making any
        adjustments in the blanket drawing dimensions as required. As
        installed the blanket length along the axis of the interconnect
        should be sufficient to cause slight compression at its ends.
        This will allow for contraction motion during cooldown,
        preventing the circumferential joints at the ends from opening.
        Make any necessary adjustments to the blankets.

    2.  Wrap the inner blanket over the heat shield. As was done for the
        pipe blankets, locate the joint to one side near the bottom to
        reduce strain on the joint. The longitudinal seam may be
        overlapped rather than butted for strength and ease of
        installation. Secure the joint with aluminum tape.

    3.  Secure the two circumferential joints at the ends that abut the
        D1 and DFBX blankets using aluminum tape.

    4.  Wrap the outer blanket over the inner one. Stagger the location
        of the joint relative to the inner joint. The longitudinal
        blanket seam may be overlapped rather than butted for strength
        and ease of installation. Secure the joint with aluminum tape.

    5.  Secure the two circumferential joints at the ends using aluminum
        tape.

28. Final Interconnect Closure

    1.  Perform electrical tests on the interconnect to CERN procedures
        before the mechanical closure is made.

    2.  Slide the large bellows from D1 where stored, bringing it over
        the interconnect space to join the D1 vacuum vessel to the DFBX.
        Support the bellows properly so as not to damage the
        convolutions during the sliding.

    3.  Bolt the sliding flange to the D1 magnet's mating flange section
        using the bolts and washers which were previously installed on
        the end dome.

    4.  Clamp the bellows ends to the mating flanges on the D1 and the
        DFBX using the claw clamps (CERN-supplied).

    5.  Perform a vacuum leak check of the insulating vacuum space if
        all other openings into the vacuum space have been previously
        closed.