Warning: before welding on this car, contact Herzog Contracting" said the sign painted on the sides of dozens and dozens of ballast cars.
Why the sign? More specifically, is that a frequent peril that car owners need to worry about? That 3rd parties will weld on cars that don't belong to them, without being asked/told to? I'd be mad as can be if I was a fleet owner,and started getting cars returned to me with the paint blistered off the sides of them.
Or is this just protection from people who might perform spot repairs that they would like to invoice the owner for?
If you set the spray-on lining on fire or mangle/short out the mechanical working innards (including solar powered battery controls for GPS dumping system, etc.), the job you save might be your own.
If a car is bad-ordered, or perhaps damaged in transit, I believe it's normal procedure for the railroad in question to perform repairs and bill (if appropriate) the owner for the work.
I'd presume that if the cars are being ferried between jobs they may not be accompanied by Herzog personnel, so could be exposed to repairable damage and the possibility of repairs thereon.
Linings could sustain damage from either arc or gas welding, as MC points out. Arc welding could turn electronics into useless junk, never mind the possibility of physical damage to said equipment if cutting or welding takes place near wiring and components.
I'd imagine that the cost of a case of spray paint and a couple stencils may be less than the cost of recoating or re-wiring a single car.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
The current used for arc-welding is a few million times what it would take to fry and vaporize the microscopic wires and chips that comprise the electronic/ electrical components and controls for them . . .
Also, you'll often see a similar warning on the frame rails of truck tractors and trailers. There, the steel is a special alloy and/ or heat-treated, and the intense heat will change the metallurgy and strength and ruin it - even to the point of making it brittle and prone to shattering under impact loads ! So that could also be a secondary concern here.
Later on I may try to find a good photo of that warning on railcarphotos.com or a similar website.
MC, I didn't know they had a "spray-on" lining. What kind, and what for ?
- Paul North.
Electric arc welding and electronics are not compatible.
Herzog ballast cars, for the most part, are used in computer controlled, GPS guided ballast train service where the entire train can be dumped in a hour or less as the ballast train is moving at 15 MPH, the cars have a lot of electronics on board. When welding is required on equipment that contains electronics, the electronic equipment must be disconnected to protect it from electrical fields that are created in the welding process.
The ballast trains are used prior to the arrival of surfacing gangs, with track time on Main Tracks being a scarce commodity the use of the Herzog (and Georgetown), computerized continuous motion ballast trains have facilitated getting ballast laid better than any prior operations the carriers have used..
Never too old to have a happy childhood!
mudchicken If you set the spray-on lining on fire or mangle/short out the mechanical working innards (including solar powered battery controls for GPS dumping system, etc.), the job you save might be your own.
Wow!! those little A-frame panels on top sort of looked like a solar array, but I figured that unlikely since I never would have expected to see solar panels on a ballast car...
So then I guess the cars dump the ballast automatically (on top of the ties) , and some other critter must follow along and raise the track long enough to tamp the ballast in underneath?
BaltACD Herzog ballast cars, for the most part, are used in computer controlled, GPS guided ballast train service where the entire train can be dumped in a hour or less as the ballast train is moving at 15 MPH, the cars have a lot of electronics on board. .
Herzog ballast cars, for the most part, are used in computer controlled, GPS guided ballast train service where the entire train can be dumped in a hour or less as the ballast train is moving at 15 MPH, the cars have a lot of electronics on board. .
I never would have imagined that ballast cars had so much tech onboard.
About 2 minutes into this video the Herzog cars are distributing ballast. Normally Herzog trains are followed by MofW personnel to ensure that switches and road crossings are cleared of any potential overflow or ballast within the switch points.
http://www.youtube.com/watch?v=RLMEi71GpxE
Also the Herzog promo video
http://www.hrsi.com/railroad_services_plus_train.php
You will also find a warning "do not ground to coupler assembly when welding" on a lot of boxcars and flat cars with hydro cushion drawbars.
Hydraulic fluid does funny and dangerous things when it boils.
One reason some car owners want to be contacted before repairs are done is that they may have their own shop, or may simply want to provide information on specific repairs they will allow foreign shops to perform.
Running the current from an arc welder through metals like aluminum rivets and cast steel parts can set up corrosion problems also.
Gas welding is normally used to cut and remove damaged parts, the preferred manner to repair and add parts is electrical arc welding, it is more precise and the heat dissipation can be managed better...arc welding only heats a small spot around where the weld is being performed, gas (flame) welding heats a larger area.
23 17 46 11
Link to a typical photo (none of these photos are mine) of one of these - HZGX 8404 - but it's too coarse, you can't really read the warnings: http://www.railcarphotos.com/PhotoDetails.php?PhotoID=709
A slightly better view of the warnings, particularly zoomed-in:
http://www.rrpicturearchives.net/showPicture.aspx?id=1576611
Ahh - here we are: http://www.rrpicturearchives.net/showPicture.aspx?id=2403524
And one of the 'slope sheets' warning:
http://www.rrpicturearchives.net/showPicture.aspx?id=2403528
Close-up photo of the "patents" placard - note also the small box to the left: http://www.rrpicturearchives.net/showPicture.aspx?id=2403520
Which has the push-button version of the electronic controls in it:
http://www.rrpicturearchives.net/showPicture.aspx?id=2012378
A good view of the "A"-frame-shape solar panels:
http://www.fortwortharchitecture.com/forum/index.php?showtopic=4198
Manufacturer's newsletter article from 2004 about the panels and how they recharge the batteries:
http://www.pulsetech.net/about/pulsetalk/2004/PTALKDLR904.PDF
Besides frying the electronics and setting the lining on fire there are other considerations. Parts of the car can be made out of a special alloy of steel that resists wear better than mild steel. These alloys need different processes and or pre and after heat treatment. Also different alloy welding rod or wire. With all the differing alloys of today's metals there are an equally numbered special procedures in dealing with repairs or build up of them.
We started using a new type of wear metal in our loader buckets. The strips of this metal were falling off after a few hundred hours of use. The welds were worn off but the strips were barely worn. After an engineer from the company came out and looked at how they were welded and with what. The procedures used were changed. Now they are pre heated and welded with a special rod and hard faced over with another special rod. So far they are holding up well after a few thousand hours.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
SO then the one question that has not been addressed directly, has been answered by default?
It IS common for foreign roads to perform repairs on rolling stock belonging to others, without permission? So they just send whatever bill and expect it to get paid?
It is understood that routine repairs will be made to cars that are off the owners property (carrier & privage owner). There is a entire segment of the rules governing the interchange of cars that deals with the interline billing of repairs.
Convicted One SO then the one question that has not been addressed directly, has been answered by default? It IS common for foreign roads to perform repairs on rolling stock belonging to others, without permission? So they just send whatever bill and expect it to get paid?
Yes minor repairs were performed on all railroad cars and billed to the owner. things like adjusting brakes or replacing brake shoes or air hoses were common. Yards often had individuals whose job it was to find things and fix them. An article in the PRR Historical Society magazine several years ago was by just such a person. he made a career out of adjusting brakes since it was one of the easiest jobs and always made sure he carried the wedges necessary to do the job. The road doing the work was probably more concerned with avoiding wrecks then car repair but they go hand in hand. Another couple of reasons for not welding on cars is because I have seen hoppers have an angle iron welded to them in the winter to shake the daylights out of a car to free frozen coal in a steel mill. Cars have had various brackets and structural shapes welded to them to fix odd loads like on a flat car. That eventually results in someone having to smooth out the deck again. Cars like covered hoppers can have coatings designed to resist corrosive effects or make the product slide easier for unloading. While ballast cars wouldn't have this ruining several thousand dollars of coatings requiring removal and recoating is expensive. Lots of reasons all with the same result. They cost the car owner some serious money to correct and they have a justifiable reason to want to have input. I'd be willing to bet they are all inspected when returned for damage also.
Con 1...
Car repair can be and often is a profitable part of railroading business.
As stated, there is an entire rule book, the Field Manual of the A.A.R. interchange rules that covers everything, from the type or grade of bolt used in a given repair to what a given gasket for a specific tank car has to be made of to how many hour must be billed for a repair, it is even more detailed than your auto dealers "shop rate" on automobile repairs.
And of course, it tells you what to charge for a specific part too.
Most RIP tracks and car repair shops buy in bulk, so while the book might say charge $150.00 for a crossover platform, your shop may have bought 500 of them at a 20% discount, so you profit.
It works like this on my railroad, and this is typical on most roads.
Say one of our member lines yards a train here, and during the routine bleed off and inspection, our car men find 6 bad order cars, with defect ranging from missing or badly worn brake shoes to a broken bell crank on a hand brake to a car that was cornered in a collision.
They write these cars up, and during switching, I place them in a rip track at our yard.
Our car department repairs the cars, and bills the member line who delivered the BO cars to us.
That's also why every outbound train is inspected, not only for the initial terminal air brake test, but to find any cars that have defects not noticed during routine handling of the car and removing them before we forward them.
By finding and removing these cars from the outbound train before it is handed off to another railroad, a railroad saves the cost of someone else repairing the car at AAR rates, your own shop fixes the car at your cost, not the AAR rate.
By inspecting every inbound car for defects, you can generate profit for your railroad repairing defects.
By inspecting every outbound car your railroad saves money.
Now for something major, like a car shows up with the side ripped out, we would set it over and contact the owner or lessor for instructions.
But just about anything else is normally billed to the railroad that either brought you the defective car or the carrier than damaged it.
The whole set up is designed to make each carrier inspect and repair cars before they are forwarded to another railroad.
This too serves a dual purpose; it keeps your AAR billing down, and insures a fleet of cars that get repaired quickly.
Car owners are not billed directly for minor damage repairs, that is handled between carriers, simply because the car owner didn't damage the car.
Routine repairs, like brake shoe changes or a gasket replacement are billed to the owner/lessor, but damaged caused by incorrect car handling is billed to the carrier that damaged the car or delivered it that way.
I believe railroads settle their AAR billing quarterly.
Excellent explanation, Ed - thanks once again ! It's consistent with what little I know about that process, and well-organized and stated better by someone who's clearly more familiar with it. Perhaps it ought to be formally published as a little article or as an "Ask Trains" column in a future issue.
Which leads me to another related question I've been wondering about: While the recent/ current economic recession has clearly led to layoffs at many levels for most railroads - have the carmen been able to minimize that impact on their ranks by being - um, a little more, say, 'zealous' - in their diligence and scrutiny of cars within their purview for defects. Not saying that anyone has fibbed or billed for or fixed something that didn't need fixing, but more in the nature of a more stringent scrutiny of each part. To invent an example, suppose a grab iron has a little bend in it and is loose at one end, but is clearly still solidly attached to the car. In the boom times, that might be passed over to avoid delaying the car and its load, even though it could have been written up to be "shopped". But now, the heck with worrying about delaying the car - if it's got a defect, that defect gets fixed, regardless of how severe it is.
What led to this thought was about a year ago, there was a short thread here about an issue with the carmen on CN at North Fond du Lac, as I recall, and an FRA inspector who was zealously marking up cars as having defects - an awful lot of cars - even though those cars had been in transit and arrived without anyone taking exception to them before that. Sure, the operating management wants to move trains and cars, not switch them out to be repaired - so that might have led to some pressure on the car people to let some marginal cars slide by. But the self-interest of the car inspectors in generating more work for their colleagues down at the Repair-In-Place track would give them an incentive to find any possible defects. So would the built-in incentives in the system and process that Ed described above. Again, thanks for that insight, too.
Anybody have any comments or thoughts on this ?
Carmen shopping cars and NFL officials calling holding are in relatively the same position....The NFL official could call holding on every play if they desired....the Carmen could find a reason to shop every car he inspects if he chooses to. From time to time and location to location you will have some 'overzealous' Carmen make a statement with their shop tags, which will tend to get managements interest to find out what the root problem is at the location.
A high incidence of shops at a location, in today's railroad, does not generate the need for additional Carmen....it generates the idea of 'outsourcing'; sending the cars to independent car shops (ie. Progress Rail and others of their kind). Today's railroads want to move income producing trains, they don't want to be saddled with operations other than those that are absolutely required to move trains and collect the income from moving them.
Paul_D_North_Jr Excellent explanation, Ed - thanks once again ! It's consistent with what little I know about that process, and well-organized and stated better by someone who's clearly more familiar with it. Perhaps it ought to be formally published as a little article or as an "Ask Trains" column in a future issue. Which leads me to another related question I've been wondering about: While the recent/ current economic recession has clearly led to layoffs at many levels for most railroads - have the carmen been able to minimize that impact on their ranks by being - um, a little more, say, 'zealous' - in their diligence and scrutiny of cars within their purview for defects. Not saying that anyone has fibbed or billed for or fixed something that didn't need fixing, but more in the nature of a more stringent scrutiny of each part. To invent an example, suppose a grab iron has a little bend in it and is loose at one end, but is clearly still solidly attached to the car. In the boom times, that might be passed over to avoid delaying the car and its load, even though it could have been written up to be "shopped". But now, the heck with worrying about delaying the car - if it's got a defect, that defect gets fixed, regardless of how severe it is. What led to this thought was about a year ago, there was a short thread here about an issue with the carmen on CN at North Fond du Lac, as I recall, and an FRA inspector who was zealously marking up cars as having defects - an awful lot of cars - even though those cars had been in transit and arrived without anyone taking exception to them before that. Sure, the operating management wants to move trains and cars, not switch them out to be repaired - so that might have led to some pressure on the car people to let some marginal cars slide by. But the self-interest of the car inspectors in generating more work for their colleagues down at the Repair-In-Place track would give them an incentive to find any possible defects. So would the built-in incentives in the system and process that Ed described above. Again, thanks for that insight, too. Anybody have any comments or thoughts on this ? - Paul North.
As BaltACD stated, if the Carmen wanted too, odds are they could find some small AAR defect with most cars.
In regards to your question, any loose safety appliance is a FRA defect and has to be repaired before the car can be used.
A bent grab iron or stirrup, as long as it is not bent beyond a certain point, and is still firmly attached and serviceable will be overlooked, but a loose grab iron and or stirrup will shop the car.
Safety appliances account for a large portion of BO cars, carmen and us ground pounders are quite aware of their importance, and on my railroad I am empowered to BO any car I find with a safety appliance missing or defective, from grab irons bent inward to the point I cannot fit may hand around it to a loose crossover platform or a handhold on the end with bad welds....in fact, I can bad order any car I find that has any defect, from a defective anglecock to sharp wheel flange.
I know on the UP and BNSF down here, most employees can BO a car in the same manner.
Stirrups and ladder rungs, along with hand brake wheels seem to be the attachment point of choice for the dummies in the industries and plants to hook their tow rope to when they want to move a car.
For some reason, they never want to use the hole or bracket designed for just that use, so we find a lot of brake wheels and bottom grab irons all bent to heck.
And because the bottom grab iron sticks out the farthest, it always seems to be the part of the car that gets wiped out whenever there is a close clearance issue.
Our carmen have a neat tool they carry, it looks like a pry bar with a bearing on or at the crook of the bend, they can straighten a bent grab iron in a few seconds with it, and as long as the rivets or bolts are still firm, it's good to go.
And to answer the second part of your question, yes, if the car department feels like furloughs are getting close, and or business and traffic are slacking off, they do find more bad orders than "normal" but I have never seen any car with a BO tag that did not have true repairs needed.
Like BaltACD said, it is somewhat up to the carmans's discretion.
If the car is in the middle of a unit grain train and the defect is not a safety appliance or does not affect the performance of the car, odds are it will be shined on.
On the other hand, if it is in the middle of a switch cut or yard transfer, or a mixed freight, it will get tagged.
I have been a welder most of my life and spent much of it welding on locomotives and rail cars. Arc,Tig,or Mig welding does not fry any electronics either on locomotives or cars running or not. If you use a voltage meter to a car or locomotive when welding you will not get a reading. The reason is the arc is formed at the point of contact and flows from positive to ground and ends there. There is no reason for the electricity to flow anywhere else but the point of contact since electricity always takes the shortest route to ground which is from the electrode to the piece of metal it contacts. If the electricity did flow to other parts of the locomotive anyone touching it would get shocked every time you stuck a arc. Even if you melt the rod and ground it out completely(no arc but rod stuck to the metal) you still won't get a reading as the current is still flowing from the rod straight to the ground. The only way you could short out electronics would be to ground the rod (no arc) straight to the computer so the electricity flows from the arc,through the computer and then to the ground. Even then I doubt it would do anything since arc welding is low voltage and high amps. Most arc welders put out 20-50 volts which is not enough to even pass through many electronics to do anything let alone short anything out. Anything under 20 volts wont even break the skin which is why you can grab both posts of a car battery and nothing will happen despite the amperage being 500 or 600 amps.
The main reason they do not want you to weld on certain parts of cars is because the metal you are welding on isn't made to hold down heavy objects with out ripping pieces of the car off or breaking the welds. On many heavy duty flat cars they have places that tell you where to weld and where not to weld. The places where you weld have very thick metal that is reinforced under the car to take a heavy strain. It is also thick so it can take the constant welding and removal(gouging) of the steel when you are cutting the supports off. If you only had 1/4" steel you would have patches all over the place to fix the holes from the last guy cutting the supports out. Another reason they don't want you to weld in other places is you are burning the paint off and sometimes also burning the numbers and letters off as well. The majority of the time if you are to do welding they want it to be on the floor of the car,or on the top sides of the car (for gondolas).
As far as welding on other peoples cars...It would depend on the car and the customer. If it is a beat up piece of junk weld it up and throw any color paint you want on it. If it is a newer car then you would probably call them up and ask them what they want you to do. It's very rare to have a new car with any problems let alone cracks. If it was a newer car most likely they would want to do the work using their people since they usually have the matching paint. Judging by those photos I can see why they would not want anyone welding on those cars. It looks like a expensive paint with ground up rubber to prevent rusting much like the paint I used to use when I welded on containers for cargo ships. Keep that paint in good shape and that car will last you 30 years.
I'm no electronics expert, but my understanding is that most such devices operate in the 1 to 2 volt range, and with current in the milliamp range - that's 1,000th of an amp. So you can see that if the welding current was occurring near the connection points for the "ground", housing, or operating devices, there would be a risk to the electronics just from the massive size of the nearby current and associated voltage - kind of like a mouse playing with an elephant !
More likely, I think, are stray currents and voltages that are induced into the metal carbody by the magnetic field from that heavy current of the welding. Each time the arc is made or broken, the current starts or stops, and a magnetic field is created or collapses, respectively. When that happens, the field induces or 'reflects' a current in anything metal nearby, and that could be enough to fry the delicate circuitry. Here's a little test: Put a portable radio playing an AM station right next to a welding operation some time, and see if static can be heard when the arc is struck and broken. If it can, that proves my point; if not, then it's bogus. Note: I'm not responsible for damage to the radio !
Paul_D_North_Jr More likely, I think, are stray currents and voltages that are induced into the metal carbody by the magnetic field from that heavy current of the welding. Each time the arc is made or broken, the current starts or stops, and a magnetic field is created or collapses, respectively. When that happens, the field induces or 'reflects' a current in anything metal nearby, and that could be enough to fry the delicate circuitry. Here's a little test: Put a portable radio playing an AM station right next to a welding operation some time, and see if static can be heard when the arc is struck and broken. If it can, that proves my point; if not, then it's bogus. Note: I'm not responsible for damage to the radio !
I'd be more concerned about the induced voltages from breaking the arc than from making the arc - the spark from the mechanical ignition systems on older cars was created when the points were opened, not closed. If the current path is close enough to the electronics and the break generates significant high frequency components (order of 1 MHz or so), then it is possible to fry electronics. If the distance between the point being welded and the ground clamp is small compared to the distance to the "sensitive" electronics, then damage is unlikely.
I'd be REALLY surprised if arc welding didn't cause interference to a nearby AM receiver. One point - cable layout will make a difference in the amount of interference, keeping the two conductors as close as possible to each other will reduce the amount of interference. Another point - much of the interference from DC welding will come from the diodes (reverse recovery).
FWIW, I am an electrical engineer and one of my specialties is RF circuitry.
- Erik
Electricity does NOT take the "shortest route", it takes ALL routes, with the amount of current in any part of the routes in inverse proportion the resistance of that part of all of them.
With large multi-part rivited equipment, if the parts the electrodes are connected to (the so called "Ground Clamp" and the welding rod) are not just one part, then there exists the possibility that the resistance between the two parts is high due rust and corrosion and thus current might flow to other parts that might put current into other connections to electronic components (so called "stray currents").
In addition, when the arc is struck there is also an electromagnetic pulse (EMP) given off that can induce currrents in anything that will conduct electricity, such as metal panels,wires, and electronic circuitry. It is quite possible for the EMP to fry a digital wristwatch on the operator of the welding equipment, or even someone standing nearby (rare, but possible!).
I am not a welder... I am the poor sap that has to go repair the result of someone welding on something without taking into consideration what WILL happen if things are not quite as they assume.
It was really hard to convince a fellow that his battery powered, (even turned off) laptop PC needed $$ repair (took out the touch pad, audio amp AND speakers) because it was on the shelf next to the work bench where he was doing TIG welding. Well... At least not until he discovered that his pocket calculator in his shirt pocket no longer worked either.
Semper Vaporo
Pkgs.
I have seen and repaired the results of someone welding on something that should have been consulted with before. We once had an outside contractor (certified bridge and highway welder) come in and do some repairs on one of our jaw crushers. No one noticed where he put the ground clamp. When it came time to start the crusher the bearings in the pitman were welded together from the current passing through. It only cost $12,000 for the six bearings and a weeks down time with over one hundred man hours labor and a crane rental. It turned out he attached the ground to the flywheel. That was the last time we hired an outside contractor. It turned out to be cheaper to pay the overtime to the employees to do maintenance.
Another time was when a plant foreman was fabricating crusher parts on the tailgate of the service truck/welder. When it came time to leave it would not start. The engine computer was fried. He did have the ground attached directly to the pieces he was welding and it still fried the computer.
So don't tell me its ok to weld on something with and without electronics without taking precautions first.
Several excellent and expanded explanations above that directly address the questions raised by the Original Post - from those who are technical experts and/ or experienced in the subject. I rest my case. Thank you.
We are just going to have to agree to disagree on this one. I think it is hard for people to understand welding unless you have been the person doing the welding. In my case I have not only welded as a career on locomotives and railcars but I have also welded on amusement park rides,ship yards cranes,automobiles,trucks and trailers,and as a contractor for the US Army. I also spent 3 years working with robotic welders in a factory. In that 25 plus years of all those jobs I have yet to fry any electronics of any kind including the computers on the 3.5 million Army Strykers.
What you people are failing to understand is many things and one of them is the basic principles of electricity and grounding. When you ground a locomotive or rail car or any piece of metal the entire object is grounded. It doesn't matter where the ground is located because you can strike a arc anywhere there is steel. Electricity will always travel the path of fastest and least resistance to the ground. In welding that ground is always the ground cable coming out of the welder which is typically no more than 6 feet away. If the electricity was traveling anywhere else you wouldn't be able to weld anything because you wouldn't get a arc to begin with. If you are getting a arc then the electricity is flowing from your rod straight to the ground creating a controlled short circuit resulting in a electrical arc and heat. It is doing exactly what it is supposed to be doing. It's not going anywhere else including taking paths of more resistance including computers.
This idea that when you try to strike an arc and the positive electricity can somehow travel through the grounded metal into a computer or other electrical device and fry something is just not possible. Every theory regarding electronics is working against you. The electricity has already found the path of least resistance and made contact with the ground and has nowhere to go nor does it want to go anywhere else. It's simply impossible to have a steel plate that is grounded and have positive electricity flowing from one end to the other. It's not possible with high or low voltage.
The other and most obvious thing you are failing to realize is the locomotive,truck,automobile,or other object is already grounded to prevent a electrical short if a positive wire hits the frame of the car or locomotive and short circuits. We can totally take welding out of the picture and just say if a traction motor cable severed and was hitting the frame of the locomotive would it fry all the electronic and kill both people in the locomotive due to electric shock? A traction motor cable is pumping around 600 volts and around 1200 amps. This is at least 3 times more powerful than any welder could ever produce. Yet what happens when it hits the frame? It grounds to the frame and goes through the wheels,to the rail,and into the earth and results in a blown fuse. No electronics are fried and the people are fine. On many of the locomotives you have a "ground relay" light that lights up when you are having short circuits and these are due mainly to traction motors shorting out.
With welding we could remove the ground completely from the welder,remove the clamp to the positive lead,and just have a bare hot wire in our hand and touch it to a locomotive and what is going to happen? Nothing. We could all be standing on the locomotive holding wires grounded to the frame in our hands and someone could take that hot wire and touch the locomotive and we wouldn't feel a thing. The reason is the locomotive is grounded. No matter where you touch the hot wire on the locomotive it is still going to travel straight to the ground.
I do understand welding bearings together and this is caused by having two pieces of steel separated just slightly to cause a arc from the ground becoming isolated by the gap. To get a basic understanding how this would happen would be to take two pieces of steel and put the ground on one plate and the electrode on the other and separate them by 1/16th of a inch. Since the positive electrodes are trying to get to the ground they will be jumping and arcing between the two plates causing heat and possibly melting the two pieces of steel together. This was poor grounding by the welder which is why you should always ground the entire object if possible rather than hooking the ground up to a shaft with bearings supporting it.
As said before try getting a reading from a voltage meter anywhere on a car or locomotive when someone is welding it. You can hook the negative to ground but where are you going to get a reading for the positive? You can probe and test every wire on that locomotive and I can guarantee you 100% you will not get a single digit. All the positive electricity is flowing right to that arc and no where else. That entire locomotive or car could be covered with hundreds of computers and nothing would ever happen. How on earth are you going to even get a positive charge to a wire to a computer if your positive wire is touching the ground? It like trying to fry the starter on your car by touching the frame of your car with the positive lead. It's not possible because the positive lead does not touch the ground it goes straight to the battery. It's no different with locomotives since the positive wires do not touch ground. Obviously with welding you are always welding to the ground and only to the ground.
That is all I have to say on this subject.
Thomas 9011 - I've done a small amount of arc welding, and managed others, so I understand most of what you're saying, and not disagreeing with it. But it's not just the principal flow of current that could cause a problem. It's what I'll call the secondary effects - the magnetic field, which can't be measured with ordinary instruments - and the small and random voltages that it could induce in the random shapes of steel - "eddy currents" and the like.
I wonder if this little experiment would illustrate the point: Sprinkle some iron or steel filings on a piece of white paper. Carefully lay it on a piece of sheet steel. Strike a couple arcs next to it - just far enough away to not set the paper on fire. See if the iron filings move and arrange themselves in some kind of pattern - probably circular, centered around the arc. I've never done this, but it seems like it might illustrate the effect. Then there's also the radio static test I suggested above, which erikem also seems to believe would demonstrate the effects.
In the end, this question is not really about what you or I think or know, or even what the actual facts are. Instead, it's that the Herzog people are conerned enough about the potential risk to put that warning on their car.
From a little Internet research, see this forum thread on the Miller Welding website - "High Frequency Welding & Car Remote Damage" - at:
http://www.millerwelds.com/resources/communities/mboard/showthread.php?14598-High-Frequency-Welding-amp-Car-Remote-Damage&s=dc38fb5ca1e9198f5fc87ec055aa9631
And this from John Deere:
http://www.deere.com/en_US/ag/servicesupport/tips/tractors/common_stories/welding_electronics.html#
Then there's this one, where many people also say that they've had no problems -
"Will mig welding on chassis damage cars ECUs?" - at:
http://www.millerwelds.com/resources/communities/mboard/showthread.php?9748-Will-mig-welding-on-chassis-damage-cars-ECU&s=dc38fb5ca1e9198f5fc87ec055aa9631
I was pulling a Reefer Trailer in 99 with a Computer Contorlled Reefer Unit. Well I got backed into at a Truckstop in AZ with a Frozen load that damaged the Trailer and needed it repaired before I could move. The area to be repaired was 52 feet away from the Reefer Unit. Repair required TIG welding. The Welder they hired said I could stay hooked up to the Trailer I did since I had to leave as soon as the repairs were finished. The Welders Currents took out a total of 5 EUC's on the Trailer and Tractor of the combo Combined. It took out the ABS computers on Both the Tractor and Trailer the Engine ECM which was a TEST one for Detroit that made them REAL HAPPY also took out the Reefer Units and the Trucks body Control Computer. The Repairs to replace the Computers came to over 25 Grand that were billed to the Insurance company of the Welding company Shop. We had even removed the ground Wires form the Batteries of the Truck and Reefer Unit Prior to the Repair being Started.
Thanks for that corroborating story, Ed.
"Upon this point, a page of history is worth a volume of logic". - Oliver Wendell Holmes, Jr., U.S. Supreme Court Justice.
That kind of thing happening - or not - is so inconsistent and unpredictable - yes, it is like lightning striking !
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