helping my gf with her physics lab hw and there's one question i don't quite understand.
When assembling large buidlings with steel frames, why would one heat the rivets before using them to join the pieces of steel? [IMG]i/expressions/face-icon-small-confused.gif[/IMG]
because hot rivets can be hammered and thats how they hold. when theyre hot theyre more pliable...so theyre easier to flatten...you know what i mean?
when you heat a solid, the molecules expand, making it softer...making the material easier to work with than when its hard.
Because they set better and tie the frame in tighter when they cool. It also allows both the frame and the rivet to conform to one another. Hope this helps. I did framing for a while.
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[hr]Originally posted by: PbFoot
because hot rivets can be hammered and thats how they hold. when theyre hot theyre more pliable...so theyre easier to flatten...you know what i mean?
when you heat a solid, the molecules expand, making it softer...making the material easier to work with than when its hard.[hr]
Molecules that make up the steel move fast when heated (goes for most objects). Faster moving molecules help for less stable form. Less Stable form = easy bending. Also, temperature has something to do with size. Heated objects will tend to shrink, but when cooling, it expands (gets larger). ex: jar full to the lid with water. Put it in the freezer and the jar will break, why? water expands when cooled. Steel is also like this because it has a liquid form. It's often seen as a solid object, only because it's freezing point is so much high.
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[hr]Originally posted by: astropunk
i dunno. but logically it would seem that it would make for tighter joints... and would set to the specific shape of the metal being joined...[hr]
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[hr]Originally posted by: astropunk
i dunno. but logically it would seem that it would make for tighter joints... and would set to the specific shape of the metal being joined...[hr]
I definately already stated that. [hr]
yeah. i noticed afterwards.. LOL.. i didnt' read the post before answering... and didn't bother changing the post...
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[hr]Originally posted by: XxSoVeReiGNxX
Heated objects will tend to shrink, but when cooling, it expands (gets larger). ex: jar full to the lid with water. Put it in the freezer and the jar will break, why? water expands when cooled. Steel is also like this because it has a liquid form. It's often seen as a solid object, only because it's freezing point is so much high.[hr]
ACTUALLY...heated objects expand and cooled objects [/i]shrink[/i]. water is the only substance that goes the opposite way. and also, not to jump all over your shit, but every substance has a gas, liquid, and solid form...so steel isnt very special. but steel is commonly in solid form because its melting point is so high, not its freezing point. sorry bud...if youre trying to answer a question, at least make sure you know what youre talking about.
I did framing for a while.
