Cooling welded connection

[The Haymaker]

I want to baby my grass and don't believe in violence so a softer blade would be more nicer

That's why I don't use a weedeater I don't believe in whip's

Okay I'll stop for now.

Don't give the PETA granola munchers any ideas!

E

 

[tthopskin@yahoo.ca]

Extreme differential cooling can crack, or strain the metal and make later cracking more likely. It is more of an issue when thick and thin are joined. When I need it quick I use a spray directed to favor cooling as uniform as possible down to a reasonable temp - then dunk to cool to touch.
larry

 

[AlbertaDan]

This is just a question I have. I seen some people to cool down welded piece by dumping it in water to be able to work on it sooner.
I always feel it should cool down on it's own.


What do you think?

Where i work (as a pipeline builder) we do a lot of welding. All of our welding is cooled slowly. when metal cools too quickly it can shock the material cauing microscopic cracks. Over time and use these cracks get bigger. Eventually leading to a failure of the weld.


Do you want to be on the machine when your FEL fails while loading something? Or how would you feel if a failure ended up hurting a family member? The few extra minutes may save a lot of grief later on.

 

[AlbertaDan]

Same as with drill bits. That's why most grinders have a water troth.

Anyone know a simple way to reharden drill bits?
Is it as simple as getting them red hot and quenching in water?

JB.

If you heat them up to red then dunk in oil to quikly cool you will harden them. But this process also makes them brittle.

Then you have to temper them so they wont break the first time you use them. This is done by heating to a specific temp then SLOWLY cooling.

**Note** all those neat colors when you heat steel represent a different temperature---light brown being coolest and bright blue being the hottest before turning red then orange.