Advice please on welding plant

[philip in china]

I want to install a heavy duty stick welder capable of running for hours and welding 2" bar and 1" plate. It does not need to be portable- in fact I would prefer it to be fixed. Space is not an issue as it will be in a barn which I am going to convert.

The main limiting factor is that the electrics are not very reliable. We cannot get 3 phase so are limited to 240 volts AC single phase.

So what do I do? Advice from experts please. Do I get a gasoline powered unit? Or do I install heavier duty cable? Would 3 phase be better and if so would a phase converter be capable of handling the current involved?

Money isn't a major consideration although obviously I would like to do things as cheaply as possible.

[moya034]

You didn't say what size/type electrodes you plan on using so it I don't know the current ranges you need. That being said, it sounds like alot. Chances are when working on stock that big, you'll probably want to also be able to do carbon arc cutting and gouging which also uses lots of current.

When you get into the world of high current, high duty cycle machines, many of them only run on 3 phase or gasoline/diesel/propane. If this machine is going to be used very regularly, running it off of electricity is going to be much cheaper then fuel in the long run. Also, don't forget to consider that the engine needs regular maintenance.

You will probably want a phase converter. However, it's hard to say if it can handle your needs. First, you need to decide exactly how many amps/duty cycle you need, pick out a machine, look at it's power requirements, then shop around for a phase converter that can fill those needs.

Now, I'm not sure what you mean by not having "reliable" electrics. I see you are in China, so if the light doesn't always turn on when you flip the switch, going with gas/diesel/propane might be the better option in those circumstances.

If you give me some more specifics, I'll be happy to recommend some welding machine models that should suit your needs.

Edited January 1, 2009 by moya034

[Ten Hammers]

Miller - Engine-Driven Welders - Bobcat 225

My suggestion ( for your rated needs ) would be using this link to start the search. Lincoln also makes excellent equipment along with others. I did a google on welding suppliers in China and got a few links to observe.

If my power supply were questionable, I would buy a motor driven unit. Questionable power sources are tough on electronics, especially new expensive electronics. I would have power FROM the unit to run other things along with the welder. The process selection on the link I posted gives you some future choices. All this relies on your availability of fossil fuel to run the unit ( in this case gasoline ). I'm fairly sure that with China's capabilities, a diesel powered unit would be available. Also note that the welder in the link is 100% duty cycle. In dealing with the stock you wish to weld ( larger sizes ), material handling issues may make having a movable welder nice although long leads will cover most of that.

I see that the unit is also rated for 200 amp @ 20 volt MIG. Have no idea if it would run a pluse unit but if it would, that would be my choice. A good compressed air system would round out the shop bringing plasma into the picture. Depends on your needs.

A gouge yes might be nice as noted ( electric ). I have run a plasma here at home shop for some time and have gouged welds with it ( them ). That said, an arc gouge is an extremely handy tool in 100% weld process or demolition/re-fit. The big eraser makes a big difference. You will need serious grinder capabilities as well. A 5 ton lift truck would be nice too. The biggest Trailblazer will handle a gouge and plasma.

I am certain that Jeremy K will know a lot on this issue. Edited January 1, 2009 by Ten Hammers

[jonathan king]

hi philip i would recomend an oil cooled unit .its a proper unit that can be used for hours on end and ive used one for many years plus in most industial workshops you will find them in use . we have a make in the uk called oxford which makes a very good unit.

[David E.]

Hi Philip, sorry I am late on this, I have a 300 amp oil cooled unit that would weld what you need, it can be run from a 60 amp 1 phase supply, 3 phase supply or like me from a split phase supply (also known as 2 phase) which is 2 (two) single phase supplies =480volt (2x240vac) Input is usually by a 3 core cable with different bridging options to cater for your supply (L1 to L3) etc etc
A 250amp oil cooled unit would probably do as well.
If you chose a phase converter, a 7.5 kw /10hp would give you enough juice to run 300 amps, any bigger than 7.5 kw converters usually have electronic sensors
to give a boost during start up and this fluctuation can damage any circuitry in a welder so make sure any converter you chose didnt have this HD booster or you will have to get a manual bypass fitted, (ask me how I know)
So a 250/300 amp oil cooled unit, 7.5 kw ph converter or get another separate 240 volt single phase supply from the nearest transformer to give you 480 volt split phase, hope this long winded reply helps.

[welder19]

If it were me I would run a new power line that would handle the demand and go with an elec. unit versus gas or diesel, if that is an option, for a couple reasons, 1- cost of fuel, 2- cost of the machine 3- cost of maint of an engine driven unit, 4- I hate listening to engines run all day long, but if you can't supply sufficient power then without question diesel versus gasoline but if you can get a propane/lpg powered unit then that would be my choice but I don't know if they have propane powered welders or not.

welder19

[SGropp]

I'd go with an inverter welder, they have the highest ratio of input power to welding current output. Some of them ,like the Miller XMT 304 CC have an auto link and can run single or 3 phase. Also they are multiprocess machines and can mig, tig, stick and gouge with the right accessories. They are only DC output and run a very smooth arc.
Not cheap,[ US$3000 and up ] but worth it IMHO
These are rugged industrial machines but do not like wild fluctuations or spikes in the line power supply!

[welderskelter]

Buy a 250 Lincoln and some 3/16 welding rod and quit trying to make this job so difficult. 240 is all I have and I wont back up from any job. Harold

[horseshoe182]

I can just see it now, philip in china, is welding in this shed, it,s getting dark, and as Phillip is welding the small towns lights are dimming on and off ,ha,ha. But Seriosly, think I,d go with desisl powered until.

[TASMITH]

If your power supply is that erratic I would definitely go with a gas/diesel powered unit. It is not just a lack of power(blackouts) that would be a concern. Under voltage and voltage spikes could be hazardous to your welder as well. With the gas powered unit you are producing your own power and at a consistent rate which will also greatly improve any welds you are doing. My 2 Cents.

Terry

[Oak Hill Forge]

My Syncrowave 300 runs on 220V single phase and will run high duty cycle and in excess of 300 AMPS if needed.