welding bms

Hi folks,

As I understand it the free cutting bms has some lead in it, is there a problem

Welding it using an arc welder?

Mick

EN1A is often refered to as freecutting but does not have lead in it, it is only EN1Apb that contains lead so you really need to know which you have.

I've just googled and found a piece on "Lincoln Electric"website and apparently it can't with much success so I

May try silver soldering

Mick

Thanks Jason I have EN1A so will give it a go

Cheers Mick

My local steel stockist always gave a verbal warning when selling en1a leaded,'do not weld this material.' en1a leaded is usually coloured on the ends with magenta coloured paint, en1a is usually green. Keep the leaded material separate in your workshop and mark the ends after cutting a piece off.

Be warned! I have 24" of EN1A Pb here and the end is painted green. yes I did buy it from a proper stockholder, and they also looked at my freshly printed colour chart with sympathy and said, don't bother, everyone has different colours...

Neil

It all depends who is doing the welding. Generally speaking everything metal can be welded (there are a few notable exceptions) and I have never had a problem with leaded steel.

graham.

My understanding is that the warnings about welding steel that may contain lead are to do with lead poisoning rather than being able to weld it?

Regards

I understood that the lead and sulphur in the metal caused cracking and porosity in the weld rather than it being a health hazard. I think it can be done with teh right rods and gasses. Galvanized is the unhealthy one.

Edited By JasonB on 17/09/2014 08:17:44

MMA welding of leaded sulphurised and phosphorised steels is possible but not easy. MIG and TIG is a non starter. The problem is that lead sulphur and phosphorus in free machining steels, are low melting point alloys. During the welding process, the steel begins to solidify from the outside of the weld inwards, this causes the lower melting point alloys to migrate to the centre of the weld. If they are present in sufficient quantity, weld porosity occurs as they solidify and shrink and lead to what is termed centreline cracking. This will not be visible but NDT will show microporous cracks within the weld line causing a weak weld. Therefore free machining steels are deemed unweldable as they are not structurally sound.

There are ways to overcome this but there are no guarantees of the weld integrity. Using a stainless rod helps with the weld process as it helps to prevent cracking, there are also specialist carbon steel rods available.

TBH I would avoid welding free machining steels unless absolutely necessary and certainly would not use them in stressed or structural applications.