Cartridge Assembly Procedure

Cartridge Bottom Assembly

• Place Cartridge Bottom (Part 6) against table with lipped edge facing down. The lipped edge will face towards the detector.



• Attach 3 Cartridge Alignment Blocks (Part 7) to Cartridge Bottom.
  
  
  • Threaded holes in Cartrige Alignment Blocks face up.
  
  
• The top of the Alignment Blocks should come even with the groove on the inside of the Cartridge Bottom. You will have to remove some material in the holes through the Cartridge Bottom for this to happen.



• Prepare Support Ring (Part 8). (CAUTION: Care must be taken while compressing ring due to internal stresses caused by compression. If control of ring is lost, it WILL fly away and can cause damage and injury).
  
  
  • Place pins in 1/8" holes nearest break in Support Ring (can tap holes with 6-32 thread and use allen screws to prevent mishaps).
  
  
  
  • Apply pressure with pliers to compress Support Ring together.
    
    
    • If Support Ring is unable to compress sufficiently, excess material from broken edge of Support Ring can be removed.
    
    
    
    
  • Place edge opposite pins into Cartridge Bottom.
  
  
  
  • Lower edge with pins into Cartridge Bottom and push Support Ring until snug against Alignment Blocks.
  
  
  
  • Release pliers and remove pins.
  
  
• Verify Alignment Blocks are flush with bottom of Support Ring. Remove more material from holes if not the case.
  
  
• Insert threaded rods into Alignment Blocks.



• Prepare Support Plate 1 (Part 9).
  
  
  • Round the sharp corners of the 7 square sockets.
  
  
  
  • On Plate 1 draw the unique line that bisects an alignment hole, the central PMT hole and one square socket hole.
    
    
    • Label the bisected socket hole 5 and in a clockwise manner label other square socket holes 4, 3, 2, 1, 7, 6 (write these numbers on the other side of the Plate as well).
    
    
  
  
  • Draw a bisecting line on the lipped side of the circular PMT socket that bisects the Pusher Rod holes.
  
  
  
  • Draw a bisecting line on the lipped side of a square socket with the angled corner in the upper left side.
  
  


• Insert Plate 1 into Cartridge Bottom with side containing the bisecting line facing down until flush with Support Ring. If the plate doesn't fit, file some of the outside off until it fints inside the Cartridge Bottom.
  
  
  • Socket 5 should align with the Guide Bolt hole on the outside of the Cartridge Bottom and the bisected alignment hole should align with the threaded rod on the opposite side of the Cartridge Bottom.
  
  
  
  • Mark position of 6 securing holes in Plate 1 against inside of Cartridge Bottom and on top of Plate 1.
  
  


• Remove Plate 1 and threaded rods.



• Rotate Support Ring until 6 holes in Support Ring are aligned with marks on Bottom Cartridge Case.



• Reinsert Plate 1 and verify holes are aligned.
  
  
  • One hole of Plate 1 may be slightly off. As long as the others are aligned, this is ok.
  
  


• Once holes are aligned, insert Guide Bolt through Cartridge Bottom and into Support Ring.
  
  
  • The securing nut might not fit in the gap of the support ring. Remove material from the nut with a file (some have to have material removed until it almost reaches the inside threads) until the filed side is snug against the support ring and the guide bolt fits through.


• Temporarily secure Plate 1 to Support Ring with 6 screws.



• Turn over Cartridge Bottom so Plate 1 is towards the table and socket 5 is facing away from you.



• Sockets are labeled by location and detector. Make sure all sockets from a detector go in the proper locations of the same Cartridge Bottom.
  
  
• Apply a small amount of white RTV around square socket with the bisecting line near the lip and insert into socket 5 with angled corner in the upper left hand side. Push until snug against Plate.
  
  
  • Rotate Cartridge Bottom and apply RTV to remaining square sockets and insert with angled corner in upper left hand side.
  
  


• Apply a small amount of white RTV to round socket near the lip and align bisecting lines with the trigger scintillating hole to the left.



• Insert Optical Connectors into 15 holes in Cartridge Bottom.
  
  
  • Place a small amount of black RTV on the threaded side of Optical Connector.
  
  
  
  • Insert Optical Connector into Cartridge Bottom with threads pointing outwards.
  
  
  
  • Secure with lock washer and nut.
  
  


• Allow Cartridge Bottom to cure overnight.

Cartridge Top Assembly

Step One

• Place completed Cartridge Bottom with lip facing towards table.



• Wrap MAPMTs with brown mailing tape and cut edge EXACTLY at top and bottom of PMT.



• Start by placing 2 thicknesses of paper onto each edge of the square sockets.



• Place PMT down into socket ensuring that the paper does not slip underneath the PMT.
  
  
  • Ensure proper alignment of PMT.
    
    
    • Looking at face of PMT, Channel 1 is in the upper left hand side. This channel should be in same corner as angled corner of socket.


• If PMT has any lateral movement, remove it and put an additional thickness of paper on each side of socket.



• Repeat until PMT has no lateral movement.



• Once all PMTs are in place, insert threaded guide bolts into Cartridge Bottom.



• Slide Support Plate 2 (Part 10) over guide bolts and over PMTs.
  
  
  • Using three pieces of tape around Cartridge Bottom ensure Plate 2 is concentric with Cartridge Bottom.


• Seal between Plate 2 and PMTs using black RTV.
  
  
  • Ensure there are no holes or silicon rubber will leak out.


• Wrap tape around bottom of circular PMT shield and insert into central hole.
  
  
  • Add tape until there is no lateral movement between PMT shield and socket.


• Seal between Plate 2 and PMT shield with black RTV.
  
  
  • Ensure there are no holes or silicon rubber will leak out.


• Remove alignment tape.



• Place Cartridge Top over Cartridge Bottom ensuring proper alignment of the Guide Bolt until snug.



• Place three long tubes over threaded alignment pins.



• Place black RTV round tubes and Plate 2.



• Allow RTV to cure overnight.

Step Two

• Ensure you are on a level surface.
• Place Cartridge Top and Bottom on level surface.
• Coat short tubes with petrolum jelly and place around Pressure screws.
• Insert Pressure screws into Plate 2.
• Make sure coated tubes are flush against Plate 2 or silicon rubber will leak out.
• Take Prototype Cylinder and attach solid lid to one side. Place lid against level surface.
  • Cover holes in lid with tape on inside.
• Mix Pink Silicon Rubber.
  • Use 10 Parts base (white) to 1 Part catalyst (pink) by weight.
  • For this part mix about 585 g (500 mL.)
• SLOWLY pour silicon rubber down onto plate 2 around the PMTs. Make sure Silicon Rubber is not leaking out.
• Continue to pour until silicon rubber is EXACTLY level to upper surface MAPMTs without flowing over.
• Pour remaining silicon rubber into Prototype Cylinder to make a sheet about 3mm thick.
• Allow silicon rubber to cure AT LEAST overnight, preferably longer (~24 hrs).
• Remove Cartridge Top from Bottom and remove papers.

Step Three

• Remove lid from Prototype Cylinder and pull silicon rubber sheet free.
• Place Support Plate 3 (Part 11) over sheet.
• Cut holes out of rubber sheet using Plate 3 as template.
• Remove Pressure screws and sleeves from Plate 2.
• Place rubber sheet over PMTs.
• Place Plate 3 over rubber sheet.
• Insert Pressure screws and screw Plate 3 down over PMTs. The Pressure screws can be used to ensure PMTs are snug against cookies when entire cartridge is assembled.

Step Four

• Wire HV Splitter for PMTs.
  • HV terminal is towards outside of Cartridge Top and ground is towards inside.
• Put female pins on HV cable end and cover pin with heatshrink tube.
• Remove about 2cm of wire mesh from each cable.
• Put heatshrink below mech to hold cable together.
• Put a single piece of wire and twist 7 leads around it and tie all wire mesh together
• Solder piece of wire into BNC connector with ground to mesh
• Attach base to L0 PMT
• Attach BNC connectors to L Bracket
• Attach L bracket to Cartridge Top
• Pass cables through top lid opening.
• Attack output cables to MAPMTs
• Group output cables together flat against each other
• Pass cables through secure mounting
• Attack secure mounting to side of Cartridge Top
• Pass cables through Cartridge Lid Top (Part 13)
• Attach Cartridge Lid Top to Cartridge Top

Cartridge Tube Assembly

Step One

• Label cookies on the Detector:
  • Looking at bottom of detector the planes are as follows: U, U', X, X', Trigger, V, V'.
    • The numbering of the 7 cookies is:
      • U = 7, U' = 1, V = 4, V' = 3, X = 6, X' = 5, U/V mixed = 2
• Insert Detector into Detector Case (Part 1).
  • Secure with screws.
• Screw Pusher Rods (Part 3) into X Frame of detector.
  • Secure with epoxy.
• Fill in corners of jig with modeling clay.
• Coat inside of jig with petrolium jelly.
• Remove screws from detector case.
• Place jig over detector with Detecor Case passing through hole in center of jig.
• Rest jig on spacer and push detector down until it is flush with level surface.
• Place Cartridge Tube (Part 2) down into jig until snug.
  • Make sure upper edge of Cartridge Tube has been rounded.
• Rotate Cartridge Tube until cutouts are perpendicular to Detector Case.
• Fill inside of Cartridge Tube with Pink silicon rubber until even with top of Detector Case.
• Allow to cure overnight to 24 hours

Step Two

• Remove jig from Cartridge Tube and from Detector Case. Reattach screw to case.
• Remove silicon rubber from cutouts of Cartridge Tube.
• Remove Plate 1 from Cartridge Bottom.
• Screw Cookies into Plate 1. Make sure trigger scintilar and pusher rod goes into the right holes.
  • Round off sharp edges of free part of socket.
  • Insert the appropriate cookie into the appropriate socket.
  • Secure with screw, washers and nuts screwing from top to bottom.
  • Make sure washers are as far in as possible.
• Pass Cartridge Tube through Cartridge Bottom with detector toward the bottom.
• Align Cartridge Bottom with Plate 1 and screw into place.
• Attach small LMB fibers to closest Optical Couple.
• Place Cartridge Collar (Part 4) into Cartridge Lid Bottom.
• Pass Cartridge Tube through Lid bottom and Collar with Collar  towards the detector.
• Pull tube until small lip is flush with Collar and screw Collar against tube.
• Screw Lid into Cartridge Bottom.
• Ensure Cartridge Top fits over Cartridge Bottom and there is slight resistance due to cookies being flush against PMTs.

Cartridge Assembly into Pot

• Ensure the Cartridge Tube is aligned with the collar.
  • Tighten the four set screws and light guide faces should be parrallel to faces on the central socket hole.
• Prepare the end of the four 5/16" collar screws. The diameter should be reduced to 6mm at the end removing about 1cm of the thread.
• Make sure the remaining thread is clean and the screws can be attached to the collar by hand.
• Attach the long rods with threaded ends to the alligment pins on the pot. Pay attention to the treads THEY ARE DIFERENT! the 4mm diameter end will match the thread in the pot. BE CAREFULL NOT TO TOUCH THE WINDOW.
• Slide the bottom part (with the detector) of the cartridge only using the rods as a guide. Push the tube carefully and make sure of the correct side the particles will hit the detector. Push the tube until the cartridge collar fits the pot collar.
• You should see if the lateral notches on pot collar are alligned with the lateral holes on cartidge collar. If they are, attach the screws. If not, pull back the tube about 5cm and turn the pot collar to the correct position (you must loose two screws on the pot collar to do this adjustment). Push the tube again and attach the lateral screws.
• Put the cylindrical nuts on the rod end. Do not overtighten, use enough torque to make sure the detector is pressed against the window
• Attach the cartridge top and use three 1/4" washers and wingnuts to hold it in place.

This page last updated: 03-Jun-2001 03:45 AM (GMT -06:00)