A1 and MO

Date 03-10-2006 11:45

I would like to know what A1 or MO signify after the rod designation?
I know what the B2, B3 and L stand for, but have never really knew what those stood for. We are also using rod now that has 4HR after the 7018. Does this signify it can be out of the oven for 4 hours?

Thank you in advance

Mike

By jwright650 (*****)

Date 03-10-2006 12:35

Mike,
About the 4HR...http://www.lincolnelectric.com/knowledge/articles/content/20faq.asp#1

http://www.lincolnelectric.com/knowledge/articles/content/lohy_des.asp

About the A1...page 44 of this pdf. ...http://content.lincolnelectric.com/pdfs/products/literature/c210.pdf
John Wright

By chall

Date 03-10-2006 12:51

That's what I call a good response.

Charles

By G.S.Crisi (****)

Date 03-10-2006 14:04

A1 means that the electrode coating contains 0.5% of molybdenium (chemical symbol Mo).
Giovanni S. Crisi
Sao Paulo - Brazil

By gerold

Date 03-10-2006 15:50

A1 and MO are the same thing. A1 is the AWS designation, while MO is a manufacturer's trade name. So while the can of electrodes may read E7018-MO for example, the AWS designation is still listed on the can (usually in small print) as E7018-A1. I wish that manufacturers would not do this as it adds confusion for some welders.

The H4R designation, which is explained well by the links from jwright650, is typically allowed to be exposed for a maximum of 9 hours out of the electrode oven before requiring a rebake, depending on which code is used and the company policy/procedures.

Chris

By jwright650 (*****)

Date 03-10-2006 16:05

Some mfgs like Lincoln, ESAB and others use their own suffix designations to add to the confusion.
John Wright

By MBlaha

Date 03-11-2006 21:06

As always, I knew I would not be let down. Thank you so much everyone. The links were most helpful as were everyones response's.

Thanks again

Mike