# Presentation: 287772

## Transmission Line (TL) Review:Design Details

**TL through Block & Beyond Design/Status****  **
**	**** **
***Bill Boettinger***** **
***FNAL***
**April 23, 2003**

## Outline

_**The design details for the target hall stripline falls into 6 separate areas, which are:**_
- Connections
- Electrical Isolation Considerations
- Supports
- Floor Stands
- Penetration pipe stands
- Power supply room wall mount
- Chase Support
- Wedge Clamps
- Vibration
- Attachment points to ground
- Isolation mounts
- Thermal Expansion
- Service Considerations

## Connections

- Minimum of 1 1/8 inch contact wide area and .005-inch thick silver-plating
- Aid in conduction across the joint (EXAMPLE 1)
- Power supply connection has a removable (non-adjustable) link
- Can be removed in the event that work has to occur on the penetration or target hall portions of the stripline.
- 		(EXAMPLES 9, 11)
- Some of the connections are adjustable
- Clamps:
- Minimum clamping force on the horn joints, with the specified contact area is approximately 3000 psi. (EXAMPLE 1)
- Clamp design has been used at MI-8 without a failure during the past 2 years worth of pulsing (9.5 million pulses).

## Electrical Isolation Considerations

- All air gaps between conductor (both like and oppositely charged conductors) maintain a 3/8-inch air gap.
- (EXAMPLE 1)
- All joints (with the exception of the power supply joint) have a minimum of 3/8-inch stacked G-10 insulator gap
- Minimum creep path length of  1/2-inch.
- Connections to the power supply have a 1/8-inch G-10 insulator stack height
- Minimum creep path length of  1/2-inch.
- (EXAMPLE showing PS pin out)
- In an effort to minimize inductance effects:
- Like charged conductor pairs have been separated (rather than dislike charged pairs) where a horn is being hooked up to the main conduction line that runs along the wall in the target hall. (EXAMPLE 11)

## 5 Types of Supports: 1.  Floor Stands

_**The floor stands**__:_
- Located on the walkway
- Support the main stripline in the target hall at a height of 53 inches off the walkway floor.
- _Design for these stands is:_
- 2 pieces of double Unistrut as the vertical support sections
- A horizontal piece of double Unistrut to transfer the load from the weight of the stripline sections (approximately 75 #/foot) to the vertical sections.
- Stripline is mounted to the horizontal section with a “swinging link”
- Has polyurethane isolation mounts so as to affect the thermal expansion as well as the vibration characteristic that the stripline will exhibit while pulsing. (EXAMPLE 4)

## Penetration pipe stands constructed of 3 bolt-on bracket/wheel combinations:
Mounted on every stabilization clamp that is in the penetration pipe. 
Wheels are polyurethane coated 
To absorb some of the shock loading from the vibration 
Two lower wheels are a fixed mount 
Take all of the weight of the stripline that is in the pipe. 
3rd wheel is mounted on top of the stripline with a spring adjustable mount 
Allow the mount to compensate for irregularities in the pipe. 
Mounting system can compensate for +- 3/4-inch differences in the inside diameter of the pipe. 

Three-point contact (with the wheels) was chosen because 3 points define a plane and if 2 points was chosen there would still be the ability to move in the direction perpendicular to the mount positions of the 2-wheel system. 
Four-point contact wasn’t implemented due to the fact that it would be very difficult to get the same pressure on all 4 wheels (sort of like a 3 legged table vs. a 4 legged table) (EXAMPLE 5)

- Mounted on every stabilization clamp that is in the penetration pipe.
- Wheels are polyurethane coated
- To absorb some of the shock loading from the vibration
- Two lower wheels are a fixed mount
- Take all of the weight of the stripline that is in the pipe.
- 3rd wheel is mounted on top of the stripline with a spring adjustable mount
- Allow the mount to compensate for irregularities in the pipe.
- Mounting system can compensate for +- 3/4-inch differences in the inside diameter of the pipe.
- Three-point contact (with the wheels) was chosen because 3 points define a plane and if 2 points was chosen there would still be the ability to move in the direction perpendicular to the mount positions of the 2-wheel system.
- Four-point contact wasn’t implemented due to the fact that it would be very difficult to get the same pressure on all 4 wheels (sort of like a 3 legged table vs. a 4 legged table) **(EXAMPLE 5)**

- 5 Types of Supports: 2.  Penetration Pipe Stands

## 5 Types of Supports: 3. PS Room Wall Mount

- The _**power supply room wall**_ mount:
- Anchors the stripline to the power supply room’s wall
- Prevents any reactionary force due to vibration or thermal expansion from entering the power supply itself.
- The mount is constructed of:
- Double Unistrut on the top and bottom surfaces
- With adjustable brackets mounted to the wall to the stripline stabilization clamps.
**(EXAMPLE 6)**

## 5 Types of Supports: 4. Chase Support

- The _**chase support**_ is the I-beam section that supports the section of stripline that goes from the main stripline over to the module itself.   (EXAMPLE 17)
- Removable section of stripline (also called the Z-section)
- Attached to a 6-inch W flange beam that is attached to the chase ledge and the module.
- Isolated by the same polyurethane “swinging links” as the main stripline is
- Links are inverted due to space constraints that are imposed by the shielding blocks that surround it
- Not possible to attach to the shielding block roof, because the block is removed to get access to the “Z-section
- Engineering calculations need to be done to see if the beam is sufficient for vibration.
- (EXAMPLE 7)

## 5 Types of Supports: 5. Wedge Clamps

- Wedge clamp is used in the stripline shielding block:
- (EXAMPLE: End view of Block)
- Provides support to the stripline in the shielding block while allowing assembly of the clamp from one side of the block.
- ‘Pushes’ against the walls of the chase and generates a 1500 lb. force with only 16 ft. lbs. of bolt torque.
- Coated with tungsten disulfide so as to allow the coefficient of friction to be low, but still allow high radiation hardness
- (EXAMPLE 8)

## Vibration: 1) Attachment Points to Ground

_**Attachment points to ground:**_
- Most of the vibration can be effectively damped by attaching the stripline (via the support system) to ground.
- (EXAMPLE 6)
- Use a support stand on the main stripline in the target hall every six feet
- Same unsupported length as has been tested at MI-8 with no apparent detrimental effects.
- In the power supply room, the wall mount should effectively damp harmful vibration from entering the room, much less the power supply.** **
- Wall mount will incorporate polyurethane isolator bushings so as to further damp the amplitude of the vibration
- (EXAMPLE 4)

## Vibration: 2) Isolation Mounts

_**Isolation mounts (“swinging links”):**_
- Consist of a steel separator bushing that is
- Mounted on a suspension rod with polyurethane compression bushings that isolate the vibration generated by the stripline from being transmitted down the stripline and also to the floor.
- Wheels on the penetration pipe stands are coated (about 1⁄2 inch thick) with the same type of polyurethane as the “swinging links” are
- Vibrations in the penetration pipe section should be minimized with the use of this material
- (EXAMPLES 4 & 5)

## Thermal Expansion

- Most _**thermal expansion**_ is taken up in the turns that are present in:
- Stripline joints and routing through the block in the chase
- “z-bar link” that connects the main stripline to the module
- (EXAMPLE: End View of Block)
_**In the straight areas**_, thermal expansion can be absorbed by the isolation mounts:
- Since they are allowed to pivot due to the polyurethane bushings that are at the ends.
- This method of “swinging links” works well for the main stripline area, but is not necessary for the 28 foot long penetration section of the stripline.
_**In the penetration to the PS room**_, the stripline is mounted on wheels and is firmly attached to the power supply room wall at one end.** **
- Mounting allows the 28 foot section to expand out into the target hall rather than expanding into the power supply room and possibly damaging the power supply.

## Service Considerations

- Joints in the stripline design are adjustable to +- 1 1/2 inches so as to allow for misalignments that can occur between as built conditions and existing drawings.
- 2 areas that don’t have this amount of adjustment (due to space limitations):
- Where the power supply attaches to the stripline
- Where the stripline attaches at the top of the module.
- (EXAMPLE 13)

## Service Considerations

- 2 removable links in the design, located at opposite ends of the 28 foot long section that goes through the penetration.
- Links are removable so as to allow removal of the 28 foot long piece of stripline should there be a reason to service that section of stripline.
- (EXAMPLES 9, 10, 11)

## Service Considerations

- 2 removable “z-bar links” that allow the operators the ability to remove the stripline before they remove the horn carriage assemblies for servicing.
- “z-bar links” are designed to allow the operator to lift the 1 piece section while the link is balanced about it’s midpoint (under crane coverage) in both x and y planes so as to make the piece easier to remove and then reinstall without damaging the silver plated ends.
- (EXAMPLES 17, 13)

## Remaining Items to Design, Concerns

- Remaining Design Issues/Items:
- Cover for Transmission line (slanted sheet aluminum)
- Put urethane in PS room wall mount
- Vibration calculation for 6” w-flange
- FINISH DRAWINGS!!!
- Concerns:
- It all seems to take so long...