I have a question or two for you fabbers.

When you make manifolds out of pre beveled pipe elbows do you re bevel them at a more manageable angle for the root purge? If you do this, how do you go about doing it and making it consistant.

If you don't do this and but the pipes up 100% no gap, approx what aperage are you useing?

If you do use a gap, about how big do you make it?

Ive tried rebeveling them, gap and no gap and havent decided what i like best yet but i dont liek having three ways to do the same 1 thing.

Welding the collectors, do you grind down the inner seam then weld them together for full penetration? or do you weld the tiny edges up, ive seemed to find that grinding the tip of the inside of the collector down then welding it with .030-.035 filler works the best to seal it all up.

 

I use a guideline 30 amps for every 1mm, thats how I was taught at school.
As for bevelling, naah I dont bother. I try to make fitment 100%, but often it varies so I have to fill in some gaps. I use 3.2mm rod for that, normally i use a 2.4mm rod.

 

ok makes sense, so you are doing about 110 amps and using 1/8th filler rod for something sched 40, single pass backpurged.

What about the rest of you guys, amperages for multi passes, rod, rebeveling or not etc.

 

For the collector I don't bevel it in any way. I cut it, weld the outside with 1/16th filler. I then weld the inside of the collector, no filler, just a fusion weld using the minimum amperage. I then port and polish all my collectors cause that's what I like to do.

I bevel all my pipe to pipe joints. I generally bevel each side to about 25 degrees. I don't like too wide a bevel, just enough to allow penetration on my root pass.

My root pass is done without filler, just a simple fusion weld. I then do my cap passes with 1/16th filler, machine at about 83 amps but not using all of it...probably about 68-74. I use a bigger lense too so my gas is set a bit high around 24cfh.

 

I think this is one of them questions that you ask 50 people and get 50 diffrent anwsers. I think its just more of preference and they way diffrent people were taught or learned

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dr.NAPIER &raquo;</TD></TR><TR><TD CLASS="quote">I think this is one of them questions that you ask 50 people and get 50 diffrent anwsers. I think its just more of preference and they way diffrent people were taught or learned</TD></TR></TABLE>

of course, im just most interested if people rebevel the pipe ends and if so what they are using to make it consistant.

 

I think most people use hand grinders, although they do make a machine that does bevel pipes but its $$$$

 

I use a belt sander for beveling, and a plate locked at an angle to the belt. I just rest the pipe on said plate and sand away. It's consistent, easy, and far better than a grinder.

 

if you want to follow proper asme procedures for boilermakers regarding pipe;
bevel, land, & gap.
gap & land should be the same as your filler rod diameter.

ex - 30deg bevel with 1/16 land should have 1/16 gap & use 1/16 filler.

that's the general procedure guideline, stainless will require backpurging, mild steel won't.