Thursday, December 04, 2008

My first 35kV solder-wipe termination!

Junior and I have started a new job, replacing old porcelain cable terminations with new ones.

This is our home for the next couple of weeks. This tent will keep the snow and rain out, but still provide ventilation through the center. It's also on wheels, so we'll be able to roll it down to the next set of terminations. The lines you see (disconnected, of course) carry 34.5 kV from the transformer secondary to another substation.


This is our first victim. The cable coming from the bottom is a single conductor (Phase C), with a lead tube around it. These cables are pressurized with nitrogen, to keep moisture out, and to provide an early warning of possible failure. If we find that a lot of nitrogen is being used, we know the cable is leaking. If the amount of nitrogen leaking out is excessive, we know that there is a problem, and it's possible that the cable will fail. The lead jacket gives excellent protection to the conductor, and allows us to solder-wipe joints together.


Junior uses a torch to melt the existing solder joint. I'm holding the pan to catch the drippings.


The old terminator came right off. What you see here is the stress cone.

I'm inserting a guide rod so the new terminator will sit properly over the existing cable.

The new one went right on. We plumbed it up, then tightened the bracket.

Here's that pot of molten lead again. My job was to ladle out the solder into a pan, and cool it to a mushy consistancy so that it was solid, but workable. As Junior needed it, I would pour a dollop of the solder onto his wiping pad, and he'd apply it to the joint where the terminator and the lead tube meet. That pot weighs about 30 lbs, full of lead.


After the joint is made, we cool it down rapidly with wet rags. We were too busy during the wiping process to take any pictures, so you just get to see the final product.



That was a lot of fun today! We're hoping that with practice, we'll decrease the time. The Bruiser was able to get two of these done in a 10 hour day, so that's our goal. For starters, though, we were happy to get one done in 8 hours, with no mistakes or injuries.