Anyone ever worked or tested out for catapillar?

[Pete.]

21% it doesn’t work like that either. Which is why you get throat gages as well as leg gages because the 2 don’t go hand in hand mathematically

Yes it does more or less unless you're comparing two different weld profiles. There will be a small ratio difference between two convex welds vs two concave welds bit the cross sectional increase is there or thereabouts.

 

[Pete.]

Having sat down and done a bit of geometry it seems that concave welds are barely affected by a small increase in leg length but convex welds are affected quite a lot, with triangle fillets in between. The chord depth is the biggest influencing factor.

 

[TechnicAl]

We used to supply Cat worldwide. I was asked to spend some time at their plant in Tosno near St Petersburg in Russia. All told I was there a month. Their productivity and quality needed improvement. There was lots of little things they were doing wrong but the main one was that every station had their gas turned up to the maximum.
Obviously to help I had to know their tolerances and they would NOT fail a weld for being 1mm too big....1mm too small would fail

 

[Pete.]

We used to supply Cat worldwide. I was asked to spend some time at their plant in Tosno near St Petersburg in Russia. All told I was there a month. Their productivity and quality needed improvement. There was lots of little things they were doing wrong but the main one was that every station had their gas turned up to the maximum.
Obviously to help I had to know their tolerances and they would NOT fail a weld for being 1mm too big....1mm too small would fail

That seals it then either they used it as an excuse to blow him off or the guy is telling a story.

 

[Richard.]

Yes it does more or less unless you're comparing two different weld profiles. There will be a small ratio difference between two convex welds vs two concave welds bit the cross sectional increase is there or thereabouts.

Pete it really doesn’t mate. I’m talking practically from a welding point of view. There are so many variables with so many effects you won’t come close to working it out without knowing the facts behind the conditions.
An increase in weld toe can be as simple as turning up the voltage slightly and everything else kept the same. Same with turning it down can decrease it. Not because it puts more or less metal in the joint but because it can displace it with wetting out and reduce throat thickness. The material going in is the same it’s just been spread out with voltage.
Process and position do the same thing. A vertical up mig weld using exactly the same conditions in the flat position will produce two different leg lengths entirely but as the conditions and speed are the same the volume of metal going in will be the same. We can’t calculate x amount of extra metal in the joint because we don’t know the reason for the increase in leg and it certainly doesn’t have to contain extra metal to increase it.

 

[Pete.]

I understand that Richard but the OP simply says that his welds were 1mm too big, not that the profile was wrong or any of the other factors. If he upped the voltage causing more wetting out and reduced throat that would affect the profile - then all those factors might have added to his fail, but he doesn't say it.

I think it's just some bullwash story used to excuse the fact that his welding wasn't up to scratch. So many people can't handle being told "sorry, you're just not good enough".

 

[Richard.]

I think it's just some bullwash story used to excuse the fact that his welding wasn't up to scratch. So many people can't handle being told "sorry, you're just not good enough".

I absolutely agree.
And yes profile changes are exactly where I was going with it and not always exceeding weld metal volume.
Even stick out changes (granted fairly excessive) can change the profile of a weld to increase the leg size but keep actual volume the same by as you rightly say changes to the profile. The important thing to realise here is like machining welding has tolerances. But unlike machining those tolerances are massive in comparison because it’s controlled by a human hand and not an accurate piece of equipment. 1mm is quite acceptable providing the toes are well blended and no undercut. I think as you say there was more to it.

 

[TechnicAl]

I understand that Richard but the OP simply says that his welds were 1mm too big, not that the profile was wrong or any of the other factors. If he upped the voltage causing more wetting out and reduced throat that would affect the profile - then all those factors might have added to his fail, but he doesn't say it.

I think it's just some bullwash story used to excuse the fact that his welding wasn't up to scratch. So many people can't handle being told "sorry, you're just not good enough".

Next time you are near any of the Big Yellows have a look at the welding.....

 

[Richard.]

I’ve never been in CAT myself but I’ve been into JCB plenty of times and they are likely to be done to the same standards. There’s no question they make a lovely job of them on the most part which you’d expect from an operation like that.

 

[TechnicAl]

I’ve never been in CAT myself but I’ve been into JCB plenty of times and they are likely to be done to the same standards. There’s no question they make a lovely job of them on the most part which you’d expect from an operation like that.

Do you think so.....In my opinion some of them are not very good.....often the joints arent filled but they are so over-engineered it doesnt matter.

 

[Richard.]

Do you think so.....In my opinion some of them are not very good.....often the joints arent filled but they are so over-engineered it doesnt matter.

Tbh Al I wasn’t there looking at them in too much detail to really tell. You could very well be right but from a walk around and a nosy at the processes things seemed to be put together quite well. Closer inspection may tell a different tale

 

[TechnicAl]

Tbh Al I wasn’t there looking at them in too much detail to really tell. You could very well be right but from a walk around and a nosy at the processes things seemed to be put together quite well. Closer inspection may tell a different tale

I once ran some training at one of the Digger manufacturers.....probably late 90s....you wouldnt believe some of the topics that were raised....Id best not say too much.....but as I said before the over engineering covers the strength and powder coating covers the aesthetics.

 

[Kent]

Thing is read and respect what they want. I remember a load of stuff Comming back from bnfl years back used fuel rod containers I think they where but just drawings of job let's to us.
Stiches had a length and if I rember correctly the length tolerance was insane and this is before we had the electronics of today
Read the drawings, study the wp and do as it says. Why? Because it don't matter if its just copy and paste a jobsworth or a very real need for reasons over your pay grade

Do as it says or don't take the job on

 

[TechnicAl]

Thing is read and respect what they want. I remember a load of stuff Comming back from bnfl years back used fuel rod containers I think they where but just drawings of job let's to us.
Stiches had a length and if I rember correctly the length tolerance was insane and this is before we had the electronics of today
Read the drawings, study the wp and do as it says. Why? Because it don't matter if its just copy and paste a jobsworth or a very real need for reasons over your pay grade

Do as it says or don't take the job on

BNFL were famous for it.......They were cladding the inside of steel tanks with stainless sheet at Sellafield....they were using sticks and they specified they had to be used straight from the oven....but ovens werent allowed as the steel feet may contaminate the stainless sheet and the heat generated may oxidise the surface....there were lots of meetings

 

[addjunkie]

BNFL were famous for it.......They were cladding the inside of steel tanks with stainless sheet at Sellafield....they were using sticks and they specified they had to be used straight from the oven....but ovens werent allowed as the steel feet may contaminate the stainless sheet and the heat generated may oxidise the surface....there were lots of meetings

Sounds familiar a procedure you cant follow, written by an engineer, reviewed by another, and given to the man who can, but he cant.

 

[TechnicAl]

Sounds familiar a procedure you cant follow, written by an engineer, reviewed by another, and given to the man who can, but he cant.

resolved by an Engineer.....it was the first time we put stainless rods in vacuum packs so they didnt need the re-bake....but it took a few meetings to get there

 

[Peloquin]

I went around the JCB Compact Products site at Cheadle 5 years ago and some of the welding was terrible. It looked like big paint runs in places.

 

[TechnicAl]

I went around the JCB Compact Products site at Cheadle 5 years ago and some of the welding was terrible. It looked like big paint runs in places.

They are all the same Rocester Uttoxeter Rugeley

 

[Kent]

BNFL were famous for it.......They were cladding the inside of steel tanks with stainless sheet at Sellafield....they were using sticks and they specified they had to be used straight from the oven....but ovens werent allowed as the steel feet may contaminate the stainless sheet and the heat generated may oxidise the surface....there were lots of meetings

That's where they wanted them actually I think was about 1988?

 

[owas]

Ive just got a job at a company thats main customer is JCB.
The quality of welding is actually really quite good but the test wasnt strict at all.
Bit of scrap to get the machine set up, then just a fillet weld on 6mm plate.