Recent content by MechEng1977

Thanks guys, so the American spec banned them or is there a reduction factor if I use them? I am assuming a bolt with a washer welded or Two nuts sandwiching a washer is preferable? What about just threaded rod alone? I don’t see this as a recommended solution

msquared48, not sure I understand your joke but I will say its too bad they don't because there are some hot ones in my building!

Great info guys, I appreciate it!

Hello, I am on the Board of Directors for my condo in Toronto and I'm wondering what is the code for the Make-Up air for a condo hallway. Is it dictated by ASHRAE or by the local building code? What is a typical value for such measurement. I assume it is listed in Air Exchange / hour? Is...

What baffles me is if pin-holes are really that detrimental, then the coating industry as we know it would not exist! I don't buy it. In my experience at a pin hole locations the material corrodes to a surface rust and then stops corroding. There is no etching of the metal.

Ok so I should cool the steel from the critical temp no quicker than 10 seconds and no longer than 166 minutes?

Yes I understand that, I'm not that slow. I don't understand a) how is the cooling rate constant? b)If we take a constant cooling rate of 40C/s, it means that from 730C to 0C, it would take 18.3 seconds. That doesn't match the x-scale which says 10^2.

What I don't get is the 40°C/s and the 5°C/s it doesn't match with the time scale on the x-axis?

This is what I don't understand: fact is, any coating be it Zinc, Phosphate, Epoxy has the potential for developing areas of 'pin-holes'. This means anything coated would be worst off than not coated at all? If this were true, the coating industry would not exist and automotive car bodies...

If I have a pin hole in a anti-corrosion paint, will corrosion be accelerated in the area where the pin hole occurs. The paint is applied to a 1080 Rail Steel. The Steel is currently corroding quite rapidly, and one of our ideas is to coat the steel with a anti-corrosion paint. One of the...

I am looking for a Fine Pearlite stucture after a piece of rail is thermite welded. The rail steel is essentially a 1080 Carbon Steel. Specifically the composition is: Weight Percentage, % Carbon, C 0.72 - 0.84 Manganese, Mn 0.70 – 1.25 Silicon, Si 0.10 – 1.00 Phosphorus, P...

The tumbleweed blows across the quiet desert landscape, with nothing in its path it faces a quiet isolation but hopefuly it will find a Material Science Expert to once again help its cause? Hahah Thanks for listening

Ok, so taking the engineering approach, I calculated the CE: ASTM A27 70/36 CE = 0.47 ASTM A148 90/60 CE = 0.48 (Assume no Ni, Cu, and Mo) (C=0.28, Mn=1.2) 105/85 CE > 0.48 (There is Ni, Cu, and Mo how much???) As for Grade 80/50, and 80/40 do you know the approx chemical comp??? If the...

Assuming all precautions for welding are taken (electrode, heat treat), and the weld is performed properly is the ASTM A148 - 90-60 more robust when compared to ASTM A27 - 70-36? Or is the 90-60 still more likely to crack in service. I just want to make sure the switch to the higher grade...

Compared to ASTM A27 - 70-36, can you compare weldability. I noticed the Manganese is less for A27, does that mean it welds better or easier?