Gingle
We are all in the same boat
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- Thread starter Gingle
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Buy a quality brand. I bought some from Toolstation and then that evening read on here about not buying cheap DIY shop rods. Can I get an arc with them, no. Can I get an arc with the quality rods that I got, so very yes.
If you want to see what rubbish is I'm more than happy to send you some of the Toolstation ones, they are of little use to me
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If you want to see what rubbish is I'm more than happy to send you some of the Toolstation ones, they are of little use to me
.
Gingle
We are all in the same boat
- Messages
- 453
- Location
- England uk Cambridge
Thanks, and a good named rod please , at a reasonable price. Bought toolstashion rods , are a bit hit and miss
Esab, Murex, Lincoln, Oerlikon, Elga, Bohler
Memmeddu
Member
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Fincord ,saf fro (probably the same as Lincoln since they acquired air liquide)
Feet 'n Inches
Out of the rat-race at last
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- Devon, GB
I've never had any problems with Siftrode. I bought some 2.5s recently, the flux coating is now coloured green - they work a treat.
Thats because they have changed supplier.......possibly chinese as most (or all) European manufacturers stopped doing green. The green dye is Chromium Oxide and we all know Cr is bad for you so why put some in just to make it coloured. Manufacturers have a very limited choice of colour additives because most dyes burn away at the baking temperatures (especially low hys) so red is iron oxide (and you will get some of that even if its not added) and a blue called Lake Blue which for a quirk can take the heat.....its relatives, yellow, green, red cant stand the heat.........you can get a yellow iron oxide but its expensive.....incidentally the Lake Blue is the dye used for Denim..
they are more rebadged stuff.....the problem being the next box maybe a different make altogether
Robert Mullins
Member
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- Salisbury, uk
Low-hydrogen? When steel is molten, as in the weld pool, it readily absorbs hydrogen, as it cools, and begins to solidify, it rejects the hydrogen immediately, resulting in a weld deposit filled of miniscule 'worm holes'
6013 have a tensile strength of 60 000 lbs, 7018s have a tensile strength of 70 000 lbs, hence the removal, and control of hydrogen levels is to increase the weld tensile strength:
Hydrogen is present in water, H,2O, hence the need to keep all electrodes dry, preferably warm/hot; oxides, nitrides, carbides will also affect weld quality, this is why all plate, and weld area should have all mill scale, rust, paint, , oil, grease water, cutting fluid removed prior to attempting the weld
6013 have a tensile strength of 60 000 lbs, 7018s have a tensile strength of 70 000 lbs, hence the removal, and control of hydrogen levels is to increase the weld tensile strength:
Hydrogen is present in water, H,2O, hence the need to keep all electrodes dry, preferably warm/hot; oxides, nitrides, carbides will also affect weld quality, this is why all plate, and weld area should have all mill scale, rust, paint, , oil, grease water, cutting fluid removed prior to attempting the weld
7018s have a different chemical base to 6013s which results in a much cleaner weld. Its that which gives the higher strength, not just the removal of hydrogen. If you look at the weld metal analysis 6013s will have lower Silicon and Manganese and thats because their chemical base (acid) wont allow the recovery of these elements, whilst the alkali base of a 7018 will (the Si Mn will be higher)....Its the Si Mn that increases the strength
spaffmonkey
Forum Supporter
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Stay clear of super6 rods also. Had nothing but issues with them. Currently using boc premium rods and bohler rods far better.
Just to make it clear. In steel hydrogen has good solubility in Austenite (the phase thats non magnetic used to advantage when heat treating without a thermomemter)....but it has limited solubililty in ferrite (the phase that forms as it cools...the magnetic bit) so the majority of the hydrogen is released at the first phase change (when its hot and wont crack)....this is why you preheat...it keeps it hot so the hydrogen can escape......any hydrogen remaining when cool can build up and reach a pressure that cracks the steel....this is why its called sold delayed cracking as it can take 72 hours to build up.....any remaining that isnt enough to make cracks can still affect the strength...it can form defects that cant bee seen on x rays etc but are there after fracture ...they are known as fish eyes.......time will release all the hydrogen and it can be helped by heating at 250 for 12 hours..
Steel doesnt do this "When steel is molten, as in the weld pool, it readily absorbs hydrogen, as it cools, and begins to solidify, it rejects the hydrogen immediately, resulting in a weld deposit filled of miniscule 'worm holes'".....this is Aluminiun.
here endeth the lesson ...sorry to preach
I just thought I should corrrect thing for anyone reading this who wants to know
Steel doesnt do this "When steel is molten, as in the weld pool, it readily absorbs hydrogen, as it cools, and begins to solidify, it rejects the hydrogen immediately, resulting in a weld deposit filled of miniscule 'worm holes'".....this is Aluminiun.
here endeth the lesson ...sorry to preach
I just thought I should corrrect thing for anyone reading this who wants to know
Robert Mullins
Member
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- Salisbury, uk
HYDROGEN
Hydrogen is absorbed into mild steel during the arc welding process with covered electrodes. The hydrogen is present in the composition of many flux coatings, and in it's moisture content, the presence of this hydrogen reduces the tensile strength of the weld
Hydrogen can diffuse out of the iron lattice when in the solid state resulting in the lowering of it's mechanical properties:
Heavy ****; learning curve
Robert Mullins
Member
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- Salisbury, uk
The science and practise of welding: A C Davies: seventh edition
Ive got the 8th edition and it says something similar but not quite what you quoted
Its says "the presence of this hydrogen reduces the tensile strength of the weld"
As I put earlier you can get what are known as fish eyes which are caused by hydrogen and will reduce the mechanical properties, but these can be eliminated by heating to 250 C for 12 hours or simply by waiting....a tensile test piece sat on a radiator for a week will do the trick
So what it says is correct but it fails to say that the loss in mechanicals is only temporary.
https://www.twi-global.com/technical-knowledge/faqs/faq-what-is-a-fish-eye-and-how-does-it-develop#:~:text=A 'fish-eye' is,inclusion, or other small defect.
And that bit that ive highlighted is how hydrogen reacts with Aluminium.....I hope you didnt get that from AC Davies
