Cooling welded connection

[Inkomodius]

I must agree with everyone who says not to quench, the only time I have quenched is if the engineer has spec'd it in the weld procedure. Which has to this time been never. And as far as quenching between passes, that is a lot of thermal cycling before it ever sees a load. Quenching causes internal stress fractures at the microscopic level, and vibration and shock loading turn them into cracks, turning into a failure. Right now I build bridges, I have built trailers, been on a pipeline, and in most cases if the atmospheric temp is to low you have to pre and post weld heat treat them. And that includes mild steel. This question is best left for an engineer but my thoughts are if your going to invest time and money into something, let it cool and do it right the first time.

 

[mechanic]

Using water on your welds will make them brittle. If it something critical don't use water. it will weaken your weld. Doing weld test in school we always laid the welded metal on the concrete floor and let cool on it's own.

 

[20 20]

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?

I allways thought this was a good idea NOT! If it is just a simple weld I'll let it cool on its own. You'll be running the risk of crack welds/metal. I did have to weld a track pad on my dozer once and actually had to put it on a flame for a couple of hrs. Then slowly turn the flame down, that weld has held great with no cracks.

 

[schmism]

small brackets and BS stuff i usually dump in a bucket so i can wire brush them, and paint them and have them in service in 5 min.

on the other hand when i welded my bucket teath on, i preheated both the bucket area and tooth, welded and again used heat to keep it warm while i beat on the weld with a ball peen for 2 min

 

[killdozerd11]

small brackets and BS stuff i usually dump in a bucket so i can wire brush them, and paint them and have them in service in 5 min.

on the other hand when i welded my bucket teath on, i preheated both the bucket area and tooth, welded and again used heat to keep it warm while i beat on the weld with a ball peen for 2 min

Backhoe teeth can only come off when back stroking the bucket they only push tighter on there mount's when digging and your going to have to grind those welds off when the teeth are replaced so your going a little overboard.

Most buckets use pins to retain teeth on there mounts
so when the operator has to replace them only require a hammer and punch and maybe a pair of vice grips and a few minutes

Instead of a welder, grinder, etc and a lot of minutes
It took me awhile to get my father to see this fact but even he finally came around

But back to the subject if the weld is something NON stress cool it fast if you want
But if it is going to be under any kind of stress i don't advise it

When i took my my certs we were not permitted to do any thing with our coupon once you turned it in for testing you could do anything you wanted to a practice coupon but not your cert coupon and i never seen anyone dunking there coupon in water

 

[ihuntbear]

on cast iron I pre heat and weld with a 7018 rod then rap it with insulation to slow down cooling

 

[killdozerd11]

on cast iron I pre heat and weld with a 7018 rod then rap it with insulation to slow down cooling

On castiron ?????????????????? 7018 ??????????

NI-rod / Beryllium copper / Brazing. Yes.... been there done that

But 7018

 

[schmism]

ok to be technical.... bucket teeth shanks were welded

the teeth themself are pin on.

Most buckets use pins to retain teeth on there mounts
so when the operator has to replace them only require a hammer and punch and maybe a pair of vice grips and a few minutes

 

[killdozerd11]

ok to be technical.... bucket teeth shanks were welded

the teeth themself are pin on.

DUHHHH
The factory usually uses a welded on type of mount.... yes
though i have seen a few that were bolt on

As far as teeth most use spring pins of one type or another but i have seen teeth that mounted with a dimple formed on the tooth and the mount mostly on tractor rippers but those don't work well at all

If you hit them going back wards for any reason they come off
But even the ones on dozers that are pinned on will come off with to much back force and cat teeth and pins are not cheap

I grew up with 2 backhoes and a lot of other equipment and trucks and tractors
Then went into the Operating Engineers now i'm semi retired
Been around the block a couple of times

 

[Transit]

Shock cooling is not a good idea. I have seen shock cooled weldment shatter like glass.