Heck of a read. I can't tell if you're actually looking for answers or if you're subtly trying to tell me you know way more about electricity than I do (if so you're probably correct). On the off chance that was an actual question about the tank I don't think it was mass so much as capacitance, although that might've been what you were getting at.
The safety wombles sound fun. I can kinda agree about access monitors to sealed spaces though: Friend of mine works in aviation and one of his horror stories was about a guy who passed out doing maintainence on the inside of a fuel tank. No one knew he was in there and they refuelled the plane. They didn't find him until the plane landed somewhere else.
Geez, what a horrible way to die. So, obviously no hole monitor person with a clipboard. Once we put up the door sheet the safety watch becomes hole monitor with a clipboard. Go out or in and you get checked off with the time of entry and time of exit.
On a ship they are far more lax but maybe shouldn't be. I've rarely had a person as a hole monitor on board a ship whether new or repair job. However, on repair jobs on ships we have to have a fire watch on the other side of bulkheads as well as in the tank we are doing hot work. Mostly fire watch just sits around with a fire extinguisher and does nothing.
Well, after years of working in welding and paying attention as well as doing my own reading at home and writing emails to manufacturers that create our machines I know a bit about HOW it works but the electronics are sort of a mystery to me. I know some of the power sources I've used have been banks of welding machines hooked up to a much larger DC source. These machines are directly controlled by windings you access with a mechanical turn dial. One way, current goes up, the other way current goes down. Far as I'm concerned they are ok but not my preferred machine. I like Lincoln and Miller machines. It seems like the manufacturers never miss a chance to come out with new machines, various settings for obscure processes we will never use. I prefer simple machines on field jobs as there's no time to learn all the details and they never come to us with a manual.
Mostly on the job I start off with what the last welder set the machine for and the welding equipment they want us to use. Say it's stick welding, I just flip the machine on and do a short weld test and see how it works and if I can weld a straight vertical bead up a plate of steel. This tells me quite a bit about the machine I am running off of and I can adjust it accordingly.
While it's true that at one time a bank of similar machines came out of the factory all calibrated into to the dial so it reads accurately , out on the field the accuracy of those meters on the machine is rarely spot on unless the machine is very new. Things happen. Weathering, rough handling, wear and tear on the internal components, etc, all can change the accuracy of what the meters are telling you so you have to start of either with the previous settings or just pick a ball park setting and adjust from there. Once it's set, you can or should be able to just weld all day. However, a machine that's failing will sometimes have erratic current flows and can't be trusted which can drive a welder nuts until he realizes this and just disconnects and switches to another power source.
I did just look up capacitance and it seems to be related to energy storage so maybe it doesn't apply as no electricity is stored in a welding cable.
I did think my finding on resistance of a very large steel structure to be highly interesting. I just assumed the resistance would be by distance in a straight line and have nothing to do with the mass but apparently, it has everything to do with the mass. I'm thinking that when you ground a machine to a large structure you are essentially charging the entire structure and since it's so massive there is a huge volume of conductive steel to transfer the energy to your welding rod or electrode. The electrons can literally just flow from all around to your electrode so the resistance is barely registering. That's my theory and no ones been able to tell me different.
It's also true that a larger cable has less resistance which is why for some projects, especially air arc gouging you really want heavy cables.
For light welding with say, 3/32 rods they have a rod holder that has a much thinner and more flexible lead on it which you can then connect to your welding cable. If you try to use such a rod holder to weld with larger rods they become overheated and uncomfortable to hold in your hand.
Just a side note, one foreman bitch who was constantly on my ass trying to find fault with me walked up mid shift and told me she needed more weld from me as I was lagging behind. Bullshit, I was doing fine and my work looked great. I had my machine set as fast as I could reasonably weld without burning it up. I was so peeved by her demands I walked over to my power source, turned the settings all the way up and then back to my wire feeder to turn that all the way up. I had to walk back and forth a couple times to balance out the power versus wire feed and then when I had it I went to town burning wire and laying down some reasonable welds but it was not as good as I was welding too fast. Not my problem, it was good enough to pass so there's that. I knew what was going to happen.
About ten minutes later my wire feeder started smoking. I smelt it before I looked up to check and sure enough, smoke was just starting. I kept welding till the dang thing burst into flames and shut down. There now. I can unhook it, go turn it and and return with a working model. Reset to normal welding settings and go back to work. I'm guessing she had seen it happen and she didn't bother me the rest of the shift. The higher settings are only valid if you are actually running a heavier wire, which they do have but you have to replace parts to use it. Those wires are for heavy output on large thick steel and are a pain to use as it leaves the cable in the weld gun very stiff and hard on the hands to maneuver for an entire shift.
No kidding. I really hope he passed out and asphixiated before he drowned. Being sealed up into a small space filling with fuel is nightmare fuel.
Yeah, that sounds like manufacturers the world over. Software is the same: Hard to sell new units if there's no "improvement".
I did just look up capacitance and it seems to be related to energy storage so maybe it doesn't apply as no electricity is stored in a welding cable.
Well, the electrons flow along the cable, but they have to come from somewhere. Ideally something with high capacitance like the earth or your giant metal tank. Assuming I understood your story right of course.
I really have to wonder how much that woman cost the company by the end. What was her qualification exactly?
I'll deal with last question first. The job was at a shipyard in Mobile Alabama back around 1995 I think.
When I first got there for a big push to quickly build casino barges for the newly legalized gambling industry she was just one of the welders like me.
She was later made a foreman because she's female and black and they wanted her for an example of how you could move up in the trade.
Actually, I could weld way better than her, had a very good relationship with all my coworkers, and was far more civil, organized and better educated on welding procedures. But then, I went to trade school to learn welding and was top of my class. But then, I'm white, love to make jokes, was only there on a subcontract rather than actually being an employee so, there's that.
She harassed me daily but never once threatened to fire me while she did fire almost one person a day, and for sure at least two or three guys a week. All black guys. So, being puzzled by her actions and attitude I asked a black coworker I was on good terms with what was going on with her, why was she always getting into it with the guys and firing them. Seriously, what was her angle?, because it seemed like she was on some kind of a mission.
My coworker started laughing and said, "Bro, she's after that white head and it's yours!". I'm confused and asked, "So why fire so many black guys?" He chuckled, "She's working her way up to you.". So firing black guys was her cover to fire me. Damn. I really didn't take him seriously though.
Also, I caught her in her office trailer with another guy while they locked the door and seriously overstayed lunch break. Of course you know what they were doing when the guy was lazy, got away with not producing more than a couple feet of weld a night and sleeping on the job.
Eventually the harassment came to a head when she tried to set me up for a reprimand by lying to the supervisor. I even proved she was lying and she went crazy screaming at me in front of the supervisor.
After I got her to walk off I turned to the supervisor and said, "See how she treats me and lies? I need to be moved to another project on one of the other ships, please!".
So he agreed to move me and after only one day sent over a friend of mine who also happened to be black. Before I left I told the supervisor they really need to put a check on her behavior as it's gonna get out of control and knowing some of the rough guys on the crew, she was going to end up hurt somehow. For me, this just seemed obvious.
We loved it. We had an old white guy for foreman who was easy to get along with and we could work our shifts with zero stress of being yelled at for no reason.
Then one day, before our shift really started we see her standing on the back of a ship across the water, just staring at us. We just stand there looking back wondering what her interest is. Maybe she thought we had been fired? For what? Because she didn't like either of us? We started doing a bit of strut dancing and grabbing our crotch just to tease her. Mistake?
Next day both of us got pulled off that ship and sent to another ship where she had just happened to come on for the project. Did she arrange this? Within minutes of starting my shift she escalated an argument with me and demanded to test a tool I claimed I need to turn in because it wasn't working properly. I had every right to turn it in and get a new one but she wouldn't allow it. She demanded to use my welding hood and I told her, no way, no how is she going to use my personal welding hood. It's my property, I paid for it and it's personal since it's going right over my face. She fired me right then and there and though I went to the office to complain they backed her up.
I went down to the bay to sit and watch the moonlight on the waves and drink beer. Next day I called in for a new job and was to leave the morning after. So I'm sitting on the bay another night just drinking beer, except now I'm in a good mood. The only other white guy on the job stopped by and told me my coworker had also been fired right after I left the yard and he had been fired. He was pissed as hell but told me that early that morning after the shift finished and she left the yard someone ran her off the road and she has a broken neck. She'll never walk again and will most likely end up a quadriplegic. Do I feel bad for her? Not really. She wouldn't let guys who have families work in peace, wouldn't respect us, berated and screamed at us, fucked another employee during work hours and at lunch break, played favorites and lied about stuff and tried to set me up. I had nothing to do with it but a good idea who did and that's between him and God. Personally, I think she got what was coming for her. Me, I'm a mild mannered guy who hates conflict but when something like this happens to a real horrible person, I find it hard to feel bad.
I also once had a supervisor who drank, let his friends who could barely weld be foremen, lied about stuff and had criminals on the crew and eventually fired me because one of his friends didn't like me.
The afternoon I was fired I had a talk with God about it. Next day I was calling around and got a new job and before I took off a coworker came to me and told me that the supervisor had been killed on the new Harley he had just purchased. Oh, forgot to mention, he was shacking up with a female employee who basically was his unwilling sex slave and wanted out. He was also married but when your wife is a thousand miles away, it's hard for her to check up on you. So that's two people who fired me who died a short time later. Gives me the creeps but I didn't feel bad about either.
Lest you think something is off here I should mention, I've worked for people I highly respected who I miss to this day and for people I despised because of how corrupt and abusive they were. When I've met people who were a pleasure to work with, I've always missed them when the project was over.
Welding equipment: While things like rod holders have shown little innovation and maybe don't need it, things like power sources have shown all sorts of innovation over the years I've been working. Some features I've loved and some not so much. The best machines are ones that are purpose built for a specific function when a company orders a whole truck load of them. Those can come with very few innovative features, sort of like beef and potatoes simplicity. I like that because new welders always start messing with unneeded features and settings.
(post is archived)