Today was a busy day! I worked on a piece older than I am. It is an industrial sized hopper used for Mixing paints.
That is a 4' ladder standing next to the thing. It was about 5' wide. That's a lot of paint/chemicals!
Here's a view of the inside:
Today's goal was to patch the holes on the side of the thing, as the welds were done VERY poorly who knows how long ago and each hole provides a substantial leak. That is not usually good when it would waste product or cause a HAZMAT spill.
Here's a closer look at the mess I was dealing with:
The whole thing HAD been sand blasted, but the welds themselves were in poor shape and all those holes/pitting/porosity in the welds were harboring whatever really nasty junk the hopper contained. I didn't grab a pick, but for each of the holes, I ground the perimeter back into a general V-shape, taking out as much of the interior weld as possible without getting too crazy. They were welded on the outside, so I wasn't too worried about grinding through, but I wanted to minimize the work needed to complete the job, while still putting a cork in the dam.
After I got the holes ground as much as I thought was necessary, I took some 2.5" diameter 1/4" thick plates that I got from my father (he works in an industrial steel shop, they make the skeletons of buildings, I dork around with smaller things, heh) and beveled the edges to match the holes as closely as I could without getting too stupid about things.
USE FLAP DISCS! Unless you are doing edge on or VERY heavy grinding, spend the extra money on flap discs. They are faster, smoother, and give you much finer control and WAY better surface finishes. Don't buy cheap ones, either. Norton is my favorite abrasives brand so far. Note, the disc you see in the pic above is NOT a Norton, but I am pretty sure it was made by Norton for another company (Radnor).
Here are a couple of pics of the plates in place, nice and flush with the holes!
Yes, my stinger is on a short leash. That's what came with the dang TIG welder. I also despise, loathe, hate, and utterly detest twist-lock stingers. (A stinger is what holds the "stick" when doing SMAW, AKA, arc or stick welding.) I think I added on at least a half hour's work twisting and untwisting the dang thing. All complaints aside, it worked and I got the job done. I have a longer ground cable on order (it didn't come in on time) and a longer stinger lead and stinger will likely be the next thing I order when I have to do a job like this next.
After lots of grinding, this is what I was left with:
In the pic below, you'll notice some undercut and porosity. It's there. It's not perfect. The metal was so nasty in those areas that no matter how far I was welding out from the patch, the stuff just melted away. I also had changed to 7018 rods and didn't change the "arc force" or "dig" control from the setting I was using for the utter junk 6010 rods I bought to burn the junk off the metal. Those 6010 rods were a waste, but, at least I didn't have to pay for them. They were part of my quote for the job.
The fourth hole on the slanted part of the hopper was so corroded you could see daylight around the weld. I did manage to plug it from the inside, but went around the worst parts of the outside just to be safe. Again, the welds are ugly because of the utter crap I was welding through.
Then finally, I did a (poor looking but good enough) cover pass on the lower plate weld, as it was really in bad shape.
I did all this right next to the boiler for the whole facility. I just missed getting rained on, too! If it had rained more than the misting that was going on in the morning, I wouldn't have been able to finish today, and that would have been annoying to me and the company, as they wanted it done by Wednesday. It was a hot, sweaty, muggy, stinky, nasty, black-booger inducing work. It was the first stick welding I've done in over two years. (Nice to know I can still manage to stick things together decently, though!) But . . . I LOVED it.
The guys at the company were highly impressed. They liked my work ethic, expertise (I had to wire my welder directly to a panel, which is cake, but, I guess impressive if you don't know how to do that and/or don't like playing with electricity, especially 3-phase 220V off a 60A breaker . . . heh) and the results. One of the guys asked if I could do aluminum, which of course I can. I was told to expect more work in the future.
I was also asked to give them my business card. And, I don't have one. Yet. However . . . I have the start of a design with the help of a very artistic and awesome friend. I'll definitely be posting more about this in the future . . . YAHOO!