4130 overlay help 1

[robietherobot]

Trying to adjust my variables trying to qualify a few procedures
4130 625 overlay base material 4130 hardness readings 233

welding variables
24 jls avg
625 stck
4 hrs PWHT
hardness came back high haz cam in as high as 319

trying to keep them between 220 and 250
Need assistance please

 

[metengr]

Assistance? You provide no meaningful information.
- 4 hrs PWHT at what temperature?????
- preheat temperature ????
- base metal thickness ????
- what is 24 jls? Joules? Your initials?

 

[robietherobot]

24 joules was the average heat input

4 Hrs pwht at 1150 1190 dictated by client

Pre heat was 400 inner pass never reached 600 average was 495

Base material was 1.25

Over lay material consisted of 309/316 over lay
625

 

[metengr]

PWHT temperature was inadequate for your required base metal HAZ. You need 1250 deg F for this hardness range. Go back to your client and discuss it. My question is what was the original heat treatment condition of the 4130? Was it quenched and tempered?

 

[stanweld]

24 joules per inch? Why so low?
How many layers?
Where does 309/316 come from? You indicated that the overlay was Alloy 625 (ENiCrMo-3) with the SMAW process.

 

[robietherobot]

quenched 1625 2 hrs water
temper 1250

We have to comply with nace as well as API 6 A

Joules are dictated in their spec for a max heat input and it is 26 joules so I am very limited.

PWHT is dictated as well they define the upper limits as well as the lower limits so i am limited there as well

The haterial hardness was 235 before we started the welding.

We have to perform a short PWHT CYCLE 4hrs as well as a LONG 16hrs it the short cycle right now just got results in and the readings in the HAZ are above the required limits

We have to qualify a stainless as well as a ENiCrMo-3 over lay

 

[metengr]

The haterial hardness was 235 before we started the welding.

So, let's think about this for a minute, you are using a 220-250 BHN range after welding for acceptance yet the original material was supplied at 235 BHN. This means your original 1150
deg F PWHT must be increased to as close to the original tempering temperature as possible to remain below 250 BHN. You have little choice.

 

[robietherobot]

I was thinking that if i used a coupon that is around 220 and tempered welded the overlay I may be able to reach what they require does this soud feasible

I am at a loss due to the constraints in their spec.I have met their hardness requirement before but the PWHT was 1225 and they rejected the procedure

 

[metengr]

I was thinking that if i used a coupon that is around 220 and tempered welded the overlay I may be able to reach what they require does this soud feasible

What? I have no clue what you are asking. If you mean starting over with 4130 material at 220 BHN, and temper bead welding to achieve your 220-250 range, I doubt this will work. Why? I don't think you understand temper bead welding.

PS I sure hope your weld procedure specifications and reports are not written with poor grammar and misspelled words.

 

[robietherobot]

I came here for assistance.I apologize for my typing and I also apologize for anything you might not understand,or any thing I may not be explainning to you properly.

I have welded 4130 on many occasions and never had the problems i am currently haveing, with the specifications I am trying to adhear to.

I am only asking for assistance not to be nit picked on every little thing I type.

I just wanted to see if any one had sudgestions.I am running out of options on how to achieve what they are wanting.Sorry to waste your time.

 

[metengr]

I was not trying to nit pick, I was only providing peer review. Go back and discuss this issue with your client. If you can present your situation by stating that you either need to use a higher tempering temperature for 4130 to start OR increase the PWHT temperature using the current material, they should understand. Good Luck.

 

[jbeckhou]

Robie

Are you welding a ring groove or flat plate?

API-6A-NACE requires a 197-235 BHN hardness range for 4130 75k material. We used the following parameters for 316/625 overlay.

Preheat, 400 F Min, Interpass, 400 to 600 F max.
Preheat Maintenance, 400 F min, during welding.
PWHT, 1150 +/- 25 F. (this is a typical PWHT) PWHT temperature cannot exceed base metal tempering temperature.

If your welding a groove, I would recomend adding 1/8" material to your test plate. After welding and PWHT, face off 1/8" This will help prevent hardness issues in the HAZ. If your welding a plate, weld 1/8" higher, face off 1/8".

If you do a search for "Hydril ASME welding", you will find a paper called Engineering Material and Process Specification. Very good paper, should help with alot of your questions.

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