My old post won't work anymore, since I have to make room on my webspace to do these. But you've all probably seen it, so no big deal.
Yesterday we had more junk to clear in the warehouse, and I brought my camera. You get to see a gamma camera head be disassembled. Oh boy!
The warehouse in daylight since the pic I took at night on the last trip sucked.
This is a 3000 system partially torn down. The 3 large plates you see are where the heads normally attach. The big center ring there rotates the heads around, the plates move them in and out, and if this was all set up in a hospital there would be a table that moves the person through the center hole area. In contrast, a 2000 system the table doesnt move and the system itself rides on rails over the patient.
To move this system, you need to take the heads off...we just never put them back on. Other than that only the covers are missing in the pic (we tossed those already).
This is a head (head 3, as indicated by those dot stickers). The top rack is full of boards that interface with all the amplifier tubes.
Here I removed the rack and the top lead plate (pictured). You can see inside the head! woo! That rats nest of wires is important. Theres one black wire per tube, and the gray cable has a connector for each tube. Black is data, gray is power. There are ~50 tubes.
Black wires removed so you can see the gray cable better. Those black wires are a bitch to remove due to the connectors that dont want to let go and very little area to grab them by. Your fingers kill after doing this. The blue connectors on the gray cable come off super easy, though.
Cables removed. This is an aluminum pressure plate. Its purpose is to keep the tubes from "falling" when the head goes upside down. The tubes have to be touching the crystal at all times. The plate is held in place by the bars you can see on either side there.
Here is the plate removed. The black stuff below is a foam piece. Using just the pressure plate would not work and things would still move. The foam sheet keeps a constant pressure on things.
Teh tubez omg! These are "hex head" tubes, hence the honeycomb look. The honeycomb is just more aluminum to keep the tubes in place and separated. There are round head tubes that are...round.
I pulled a tube out to show you.
All the tubes removed except the smaller ones (those are called "half hex", and are used to fill in the edges). You still see the aluminum honeycomb and below that...the crystal!
Crystal! Encased in some plastic and on the other side is thin aluminum, the crystal is the most expensive part of the system. These crystals are specially made (though I dont know the exact makeup of them) and grown. You know those "Grow your own crystal!" kits? Its kind of like that. These are made from one solid crystal...I'd love to see what they look like before they slice them. Must be huge.
It looks kind of smeary from the optical grease all over it. Thats what you use to attach the tubes to it.
The bucket with everything removed. The bucket is made of solid lead. Its heavy as fuck even with the crap taken out.
The crystal all by itself.
So thats how you take a head apart. We kept some tubes but most of them we just threw away. I took 2 heads apart myself, and spent a lot of the evening hours moving junk and loading up the trailer of the keeper stuff. However...we had to get rid of the gantry itself.
After putting the gantry on a skid loader thingy, we could move it around. Great, except the dock has an incline to it. There was no way we could safely push it out there, and its not something you want to have fall over. We needed to lighten it up, and pretty much the only thing left was to remove the ring.
Here we are hooking it up to an engine hoist with an extension my dad welded up some time ago. We have 200lbs of extra weight added to the back of the hoist to help it stay balanced.
Released! The ring is mostly solid aluminum, and attached to is is the ring gear. The ring gear is used to rotate the whole thing around. You can see the rotate gear in the 2nd pic (small round gear on the gantry) and the ring gear (big black stripe on the ring). The ring gear is made of hardened steel. Amazingly, some places will want the ring gear replaced. Holy crap, could you imagine?
After much screwing about and such, we got it down onto a small skid. Then we weaseled it onto a larger skid for moving.
Here we have the ring and the gantry all pushed onto the dock. So ends a successful night with few injuries!
Here is a bonus picture for you!
My dad broke a tube when he was removing a bunch, so I went to town taking it apart. I'd never seen the inside of one. They have these copper "trays" in them. Look how shiny that stuff is! Those things are 11 years old, but have been in a vacuum the entire time.
