Electrode SFA Numbers ans allowance

[thandion]

Good evening,

I have a procedure based on stick SMAW electrode E7018-G-H4R SFA 5.5 numbered.

Am I allowed to use SFA 5.1 numbered E7018-1 H4 electrode instead. Is it strictly essential variable or are there some variations. Code is API 1104, but couldnt find in it.

Thanks,

 

[bernoullies123]

Refer to 5.4.2.6. For (a) no need to re qualify (b) for you to confirm.

 

[thandion]

Thank you, mine is X60 material so I can change electrode in same group.

 

[denlow60]

SFA 5.1 E7018 -1 H4 and SFA 5.5 E7018 - G - H4R electrodes are not in the same group .

 

[DekDee]

They are both Group 3 as per Table 1 and material is acceptable as per (b) so as bernoullies123 has stated - no requalification necessary.
Regards,
DD

 

[denlow60]

Hoi DekDee ,

yes these are in a group , but the mechanical properties between X60 and E7018 - 1H4 are incorrect .
just look at this pdf.

Denlow

 

[thandion]

Yes denlow60,

Their mechanical strenghts are different and normally I wouldn't prefer to use SFA 5.1 on X60 pipe. But due to the procurement issues this was my only choice and looks like API 1104 allows it.
Regards,

 

[DekDee]

denlow,
Not sure where your electrode Table comes from ? - no identification.
I only have very old copies of SFA 5.1 and SFA 5.5 but the Tensiles and Yields are almost identical.
E7018 (5.1) TS = 482 Mpa Yield = 399 Mpa
E7018-G (5.5) TS = 480 Mpa Yield = 390 Mpa

There are only two essential variables noted in 5.4.2.6 and thandion complies with both of them.

The paragraph that I think you are alluding to has "should" (recommended practice) and not "shall" (mandatory).

If his original PQR for the SFA 5.5 electrodes complied with the tensile and yield requirements of API 1104 and his mechanical properties for the SFA 5.1 are nearly identical (actually slightly higher) then there is no reason why his SFA 5.1 cannot be used.

Just remember - the mechanical properties listed in SFA 5.1 / 5.5 are minimum only.
I went into my database and grabbed the first batch certs I could find.
Kobelco E7018 (SFA 5.1) TS = 560 Mpa YS = 500 Mpa
Kobelco E7018-1 (SFA 5.1) TS = 565 YS = 483
Cheers,
DD

 

[denlow60]

DekDee ,

5.4.2.6 Filler Metal
The following changes in filler metal constitute essential variables:

a) a change from one filler metal group to another (see Table 1);

b) for materials with a SMYS greater than or equal to that of the material specified as API 5L Grade X65, a change in
the AWS classification of the filler metal (see 5.4.2.2).
Changes in filler metal within filler metal groups may be made within the material groups specified in 5.4.2.2.
The compatibility of the base material and the filler metal should be considered from the standpoint of mechanical properties.


here is a other file: BPVC 2013 SECTION II, PART C and the first file is also BPVC 2013 SECTION II

 

[denlow60]

I verged the file here it is