Repairing cast A351 Gr. HK40 baffle plate
Repairing cast A351 Gr. HK40 baffle plate
(OP)
Admin please delete the duplicate of this post submitted earlier without a subject.
Hello all,
We are revamping some old ethylene furnaces. A baffle plate (18mm thick casting - ASTM A351 Gr. HK40) has broken loose in the Hot steam superheat pipes area of the furnace above the firebox. So for being able to pull the new hot steam tubes in place our construction wants to have an ad-hoc solution to the issue by basically "glueing" the baffle plate together. I'm saying glueing meaning welding but without any proper assessment, WPS/PQR and not even consulting for a proper filler material. So they just used what was at hand from fillers and that was ErCrMo-3... 65% Ni... The ASTM recommends to use matching filler for casting repairs but in this case we have 65% Ni of the filler against 20% Ni of the plate... I'm not a welding engineer or metallurgist but something is telling me that this isn't right.
However, I understand the urgent need for them to be able to pull these pipes on time and to finish the project on schedule... as usual - our client doesn't seem to care (as we are providing them Mech. guarantee for 2 years at least). So we are welding without WPS/PQR and client approval... They said they'll preheat to 200 Deg C (in order to avoid the need for PWHT). Unfortunately we do not have Er 310H consumable available here, which I think would be best to be used in this case. What we have in stock besides above is Er 308H, ErNiCr-3.
Please tell me:
- what would be the best suitable material from the available ones in our stock?
- if we preheat to 200 C, do we still need to do PWHT?
- Any other thoughts?
Thanks to all in advance
Hello all,
We are revamping some old ethylene furnaces. A baffle plate (18mm thick casting - ASTM A351 Gr. HK40) has broken loose in the Hot steam superheat pipes area of the furnace above the firebox. So for being able to pull the new hot steam tubes in place our construction wants to have an ad-hoc solution to the issue by basically "glueing" the baffle plate together. I'm saying glueing meaning welding but without any proper assessment, WPS/PQR and not even consulting for a proper filler material. So they just used what was at hand from fillers and that was ErCrMo-3... 65% Ni... The ASTM recommends to use matching filler for casting repairs but in this case we have 65% Ni of the filler against 20% Ni of the plate... I'm not a welding engineer or metallurgist but something is telling me that this isn't right.
However, I understand the urgent need for them to be able to pull these pipes on time and to finish the project on schedule... as usual - our client doesn't seem to care (as we are providing them Mech. guarantee for 2 years at least). So we are welding without WPS/PQR and client approval... They said they'll preheat to 200 Deg C (in order to avoid the need for PWHT). Unfortunately we do not have Er 310H consumable available here, which I think would be best to be used in this case. What we have in stock besides above is Er 308H, ErNiCr-3.
Please tell me:
- what would be the best suitable material from the available ones in our stock?
- if we preheat to 200 C, do we still need to do PWHT?
- Any other thoughts?
Thanks to all in advance





RE: Repairing cast A351 Gr. HK40 baffle plate
RE: Repairing cast A351 Gr. HK40 baffle plate
Using a higher grade Ni electrode is helpful in reducing cracks during welding.
No preheat required.
Caution, my comments are general in nature to HK40 grade casting, but not specific to parts in ethylene furnace.
_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year
RE: Repairing cast A351 Gr. HK40 baffle plate
Arunmrao, what do you mean by a higher grade Ni electrode? Like ErCrMo-3? It has 60% Ni - is that what you mean?
Metengr ErCr-3 was also my suggestion from what we have at hand. However, since they are going to be pulling 16 meter pipes through this plate I hope this structure will withstand this. Again, this is totally of the records / ad-hoc solution (at least our guys try to make everyone see it that way).
Arunmrao, definetly carburising has taken it's toll on the plate but a weldability test showed no cracks using ErCrMo-3 filler with 200 deg preheat.
RE: Repairing cast A351 Gr. HK40 baffle plate
RE: Repairing cast A351 Gr. HK40 baffle plate
The fact that a 18 mm thick casting has cracked must ring alarm bells. The casting has possibly embrittled due to carburisation and exposure to high temperatures.
You may drop test a new 18mm thick casting ,it will not crack.
_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year
RE: Repairing cast A351 Gr. HK40 baffle plate
RE: Repairing cast A351 Gr. HK40 baffle plate
You can use the higher nickel-base filler. However, you stated earlier what you have on hand for weld repair. If you decide to purchase ERNiCrMo-3 for repair I would purchase the matching filler metal as mentioned in your earlier post.
RE: Repairing cast A351 Gr. HK40 baffle plate
RE: Repairing cast A351 Gr. HK40 baffle plate
_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year