# Presentation: 483172

## Transmission Line (TL) Review

**WBS 1.1.3  *****Power Supply System***
**Transmission Line (TL) Review**
***Nancy Grossman***** **
***FNAL***
**April 23, 2003**

## Outline

**Overview & Specifications ****	****	****	****  ****(N. Grossman, 10’)**
- Scope of review
- General Layout & Overall Specifications
- Schedule, Concerns
**Response to Recommendations (2/26/02 review)****	****  ****(N. Grossman, 10’)**
**Testing at MI8****	****	****	****	****	****  (J. Hylen, 15’)**
- Remote clamp & joint testing so far
- Future plans
**Ionization Calculations****	****	****	****	****  (J. Hylen, 10’)**
**Cooling Calculations   ****	****	****	****	**** (A. Stefanik, 10’)**
**TL through Block & Beyond Design/Status  ****	**** (B. Boettinger, 45’)**
- Design (clamps, connection, supports)
- Heating/cooling (expansion) & Vibration Issues
- Service Considerations

## Scope and Conceptual Layout:Target Hall Transmission

- Scope and Conceptual Layout:Target Hall Transmission

- Material: Aluminum, Dimensions:  12 inches wide by 3/8 inch thick
- Width:  Stripline nominal width is 12 inches, reduce to 8” from below clamp to horns.
- Gap: Stripline nominal spacing between bars is 3/8 inch, can increase in flex region.

- HORN 1 JOINT

-  HORN 2 JOINT

- REMOTE CLAMP

- REMOTE CLAMP

- ROCK WALL BETWEEN PS ROOM AND TARGET HALL- 23’

**REMOVABLE** **Z-BAR**

**REMOVABLE Z-BAR**

**REMOVABLE** **28’ SECTION**

## Scope and Conceptual Layout:Target Hall Transmission

## Scope/Charge to Group

**Scope Includes:**
- Transmission Line design from joint/remote clamp to connection at capacitor bank
**Electrical Isolation Considerations**
**Heating/cooling (thermal expansion)**
**Vibration**
- Stands & support structures to hold transmission line in place
**Wedge clamps in the transmission line block**
**Support stands in the target hall**
**Three point support structure in 24” round penetration from hall to PS room**
- Service Considerations
**Removing the section through the wall **
**Horn replacement**
- Cover to protect transmission line – to be designed, simple slanted sheet metal
**Charge:**
- Look at overall design.
- Consider QA, longevity, ESH issues.
- Comment back to _[grossman](mailto:grossman@fnal.gov)__[@](mailto:grossman@fnal.gov)__[fnal](mailto:grossman@fnal.gov)__[.](mailto:grossman@fnal.gov)__[gov](mailto:grossman@fnal.gov)_ within a week.

## MI-8 Fingers, Remote Clamp

- Remote clamp plugged in @ MI-8

- Horn 1 joint/electrical plug @ MI-8

- Routine pulsing of prototype horn 1, production horn 1 joint, remote clamp underway: ~370,000 pulses to date.
- Goal is 1 million pulses, 1/2 offset/flexed

## Joints and Remote Clamp

- Horn 2 joint in machine shop (now done)

- Horn 1 joint, remote clamp at MI-8

## Overall Specifications/Concerns

**1.   Lifetime:**
- Part of stripline connected to horn will be replaced each time a horn is replaced, ~>1 year.
- Part of stripline within stripline block (includes clamp) does not have to be replaced every time a horn is replaced, but we will most likely have a spare just in case.
- Lifetime of NuMI ~ 10 years
**2.****	****Radiation Environment such that ceramics must be used near the beam, but     **
**      ****not necessary above the module/T-blocks.**
- Ceramics spacers from horn to top of module/block
- G-10 spacers used beyond that as insulators
**3.****	****Vibration, keep to a minimum everywhere.**
- Biggest horn vibration is from stripline (MI8 measurements)
- Not near horn natural frequencies (200 Hz), damping times short wrt rep-rate
- Clamp every 12” in target hall
**Pulsed for about 9.5 millions pulses at MI-8 (non-joint portion of transmission line) with no problems – clamping every 12”**
- More on recent vibration measurements from Jim.

## Overall Specifications/Concerns

**4. Cooling**
- Target chase cooled by ~24,000 cfm flowing in the beam direction in the horn region and back in the opposite direction between the top of the T-blocks and the concrete cap.
- Beam heating: ~183 KW/m3 (transmission line near the beam)
- TL Electrical heating: ~27 KW/m3 (flex joint number)
- Assume air cooling from target chase is sufficient (A. Stefanik talk)
- Want air flow through TL shield block from top of module to horn (this air flow cools stripline)
- Air dam is needed at the H-block cover between the module and the stripline along the target hall wall (intended to contain air-borne radiation).
**5.  Service Considerations:****	**
- Must not block survey holes in T-blocks just off module ends, need direct vertical line of sight.
- Two removable sections to allow removal of section through the wall (28’).
- Removable “z-bar”s at top of module/block.  Allows replacement of horns.

## Transmission Line: Through the Block

## Transmission Line: Through the Block

- ( figure slightly
-  out of date )

## Transmission Line: Through the Block

## Transmission Line: Beyond the Shielding

## Transmission Line: Beyond the Shielding

## Transmission Line: Beyond the Shielding

## Transmission Line: Through the Rock Wall

## Transmission Line: Through the Rock Wall

## Response to Recommendations: Horn PS/TL Review (August 2001)

- Consider using a dynamic type fastener (e.g., spiralock nut) in the clamp joints and stripline support brackets.
- This is being done, except in the block region where it is tack-welded to the fasteners.
- Consider measuring bolt preload in critical connections by measuring bolt stretch as opposed to bolt torque.
- Not sure how to implement this – ideas?
- Consider longitudinal damping along the TL section along the Target Hall wall to damp out possible undamped vibrations from electrical pulsing.
- Using polyeruthane isolators and swinging end-links (see Bill’s talk).
- Worry about scratching the silver-plating off the TL “fingers” when clamping/unclamping.
- Have seen no damage in the silver-plating on the TL fingers out at MI-8 and they have been connected and disconnected a few times. (more from Jim)

## Response to Recommendations:TL, Remote Clamp, TL Block Review (Feb. 2002)

- Flex Joint Comments (joint with slits)
- No longer using a joint with slits.  ANSYS shows we can get sufficient flexibility with the non-slitted design.  Single strip force tests agree with the ANSYS analysis.  Testing at MI-8 of the horn1 joint is going well.  More from Jim – not specifically part of this review.
- Suggest quantitative measurements be made at MI-8 (deflection at specific points, resonant frequencies, etc.) to compare to ANSYS calculations (and any other calculations) and thus support longevity estimates.
- We are making some quantitative measurements at MI-8 and will compare measurements with predictions– Jim will talk about this.
- Concerns abut a tight testing schedule at MI-8 which might be hard to meet if problems are encountered.
- Agree. We have encountered problems, testing is tight, and we hope to make it (more from Jim).  Can delay installation of horn PS & continue testing longer.
- Concerns with human resources – lack of.
- This is a constant battle we continue to fight.
- Suggest pre-assemble entire setup (power supply to horns) at MI-8.
- We will do this to the extent that we can.

## Schedule & Concerns

_**Schedule:**_
- MI-8 testing until Horn PS removed for installation.
**Test pulsing of horn 1 and horn 2 on test stand.**

## Schedule & Concerns

_**Specific Concerns:**_
- Making sure all bolts on the TL clamps are tighten (and remain tightened)
- Checkout checklist item
- Periodic checks in Target Hall?
- QA that clamps are put together correctly
- If doesn’t look like it is going together well, stop and ask expert.
- Alignment rods at removable sections
_**General Concerns:**_
- Resources (manpower)
- Engineering/drafting to get the design done and parts ordered/made
- Technicians to get it assembled and installed
- Fitting it all in with the target hall shield block installation & Module installation
- Concerns about damaging the TL parts
- Final connections of the TL to the horns/PS are near the critical path
**The transmission line (and joint) have always been underestimated in their complexity (cost, time to make, problems encountered in installation/testing).**