SAME HEAT.. DIFFERENT CHEMISTRY 1

[mnthiraviam]

I have a case where there are two bolts

1. one is 12M-1.75*45mm
and 2. another one is 12M-1.75*35mm
1.75 is thread
12M is bolt size
45 and 35 is bolt length.

Now the supplier has provided MTC for both with the same heat number but different chemical properties...

Is this possible??

 

[arunmrao]

It is a fabricated certificate, in my opinion.

 

[TonyD71502]

I agree with arunmrao. Fake certs are not uncommon, especially when you need it to say M&M in America.

 

[MintJulep]

I don't necessarily agree yet.

How different are the chemistries, and what elements are different?

Are they both "in spec", but just a bit different?

Is there any reason to expect that all of the screws came from the same wire, or even the same batch of wire?

It seems entirely possible that - rightly or wrongly - they decided that these two bolt sizes were "close enough" that they could be run through the oven together.

See Tip #7:

http://www.heat-treat-doctor.com/documents/Fasteners.pdf

 

[mnthiraviam]

@Mr. MintJulep

I have attached the MTC Copy for your reference, please suggest ur opinion now

[/URL] ]..

Regards

 

[mnthiraviam]

I have uploaded the certificate copies...

Please review and comment.

Regards
MNT

 

[redpicker]

I would contact the supplier as there is probably a typo or clerical error involved. The chemistries are different enough that I would not expect them to be two analyses from the Heat/Cast, as the documents imply. Only the supplier is going to be able to explain this to you, however,

rp

 

[MintJulep]

Ok, I agree something is not right.

Look at dates, certificate numbers, order numbers.

Also, the sizes listed on the certs do not match the sizes stated in your first post.

Lot size is listed as 50,000 parts. How many parts were tested? One of each? That's pointless.

 

[stanweld]

The chemistry on the MTRs for each heat are indicative of a "fabricated" certificate. There is no way that the sulfur contents could be so disparate.

 

[redpicker]

"Never attribute to malice that which is adequately explained by stupidity"

While it is possible you are looking at a "fabricated" certificate, it is equally likely (or perhaps even more likely) that we are looking just at a clerical error. A little more research would be needed to determine whether or not fraud is at the root.

Please, contact the supplier for an explanation. Then, you can formulate an opinion on whether or not the information on the certificate is intentionally falsafied or not.

rp

 

[gtaw]

The chemistry of an ingot or a billet is not homogenous. As a result, the chemistry of a long bar rolled from an ingot or billet will vary slightly. Some of the values listed by the material test reports provided do look "interesting" and definitely justify further checking.

Best regards - Al

 

[MintJulep]

50,000 bolts at 50 mm long + 50,000 bolts at 55 mm long --> more than 5,000 meters of rod or wire stock.

That's something in excess of 11,000 kg of steel.

And from all of that there were TWO bolts tested.

It doesn't matter if these certs are legitimate or forged. They are worthless.

 

[Aakashjha]

Before going for any conclusion , we also need to under stand, the pouring situation,
If the pouring is carried out in diffreent slab, then due to delay in pouring there may be chances for chemistry change (Minor).
I have witnessed this situation..


Regards
Aakash Jha

 

[stanweld]

The MTR's are "Certified Copies of the Original" provided by the Exporter. Could some lowly paid, clerk typist make a mistake and it not be caught by the Certifier, of course - or Not!