ASTM A 217 WC 6 Welding

[TWR2]

Good afternoon:

I am looking for proper weld rod to use on ASTM A 217 WC 6 cast alloy. Castings are hightemperature use, not used pressure containing service.

Best Regards,

TWR2

 

[GRoberts]

E8018-B2 or ER80S-B2. Are you going to PWHT? It is necessary for this alloy with a few exceptions. If you are doing one of the exceptions, you can use 7018-B2L.

 

[metengr]

I would not recommend using any L grade weld rod for repairs to these types of castings if used for elevated temperature service only because of reduced creep strength in comparison to the base metal.

 

[TWR2]

The castings are large (2000lbs) and in a remote area. We will do some weld repair to build up non critical areas of the casting.
I would like to do the repair on the shop floor. The castings will then be placed in operation (600-800 deg F)

Pre and Post HT would be limited to shop capability.

 

[arunmrao]

Are these girth gear castings? You can use wrap around induction heaters in the weld repair zone for pre and post welding purposes,

Chocolates,men,coffee: are somethings liked better rich!!
(noticed in a coffee shop)

 

[TWR2]

No they are not gear castings.
Thank you for suggestion of wrap around heaters.
Am trying to establish if there is a rod that can be used with out haveing to post/pre heat treat. The area of weld is non structural.

GRoberts- you say "If you are doing one of the exceptions, you can use 7018-B2L" What are teh exceptions.

 

[arunmrao]

TWR2
How about qualifying weld electrodes,by making test coupons of the ASTM A 217 gr WC 6 and joining them with different electrodes. You could then get specimens and test for all the mechanical properties and microstructures that you are seeking.



Chocolates,men,coffee: are somethings liked better rich!!
(noticed in a coffee shop)

 

[TWR2]

arunmrao

Again a viable option,though timely. Looking for a simple quick solution easily applied in the field.

Not concerned with structural strenght,as there is no structural demands on area, or adjoining areas.

 

[stanweld]

You could try the NBIC Method 4 temper bead welding techniques to make the repairs. Review QW-290 of ASME Section IX.

 

[metengr]

TWR2;
SA 217 WC6 is weldable with E8018 B2. I would suggest that if your repairs are considered minor (not structural) and are under 1/2" nominal deposit thickness, and if you don't have time and what you state is accurate regarding service use, you can use the following suggestion for weld repair to this casting, at your own risk;

1. Apply a local preheat of 400 deg F.

2. Use 3/32" E8018 B2 (low hydrogen) weld electrodes (SMAW process) and deposit 2 passes over the entire excavation surface and extend 3/16" on to the original surface of the casting surrounding the excavation.

3. After the first two passes have been deposited, switch to a 1/8" diameter electrode, E8018 B2 (low hydrogen) and finish filling the excavation while remaining on top of the first two passes.

4. Add one additional pass after the excavation has been completely filled again while remaining on top of the original 2 passes, which will be subsequently ground off to make the weld repair region substantially flush with surrounding base material.


5. Perform a final wet fluorescent MT or liquid penetrant inspection of the weld repair region.

 

[TWR2]

Thank you gentlemen for your insight, I greatly appreciate it.

Regards,

TWR

 

[GRoberts]

"The exceptions" being one of the few exeptions where PWHT is not necessary. The 7018-B2L will have a lower hardness and less prone to cracking in the weld & HAZ due to lower strength and thus lower stress placed on the repair area. However, as Metengr mentions, the B2L electrode can compromise creep strength if used in the wrong situations.