Heat Treat Inquiry - 4130 Material - Sour Service - Yield @ 400°F >68,500? API6A

[Macdost]

Hi,

Forged part(s) ~220 lbs. each
Material Grade - 4130
Sour service
Yield needs to be >68,500 with testing done at 400°F

At room temperature we hit ~75,000 yield for this.

According to API 6A Appendix G, for 4130 you need to de-rate the material 88% for a testing temperature 400°F, which would put us under the 68,500 (66,000)

Looking for heat treat recommendations and/or other insights

Thank you in advance!

 

[metengr]

For sour service, you would need to have this material in a fully quenched and tempered condition for a maximum hardness of 22 HRC scale, per NACE MR0175. The tempering temperature would be close to 1200 deg F for 4130.

 

[Macdost]

Water Quench – 1600°f - 5 hours
Temper – 1215°f - 6 hours
Hardness – 235 Bhn

Results:
Tensile – 400°F - 88,000 psi
Yield – Request 70,000 400°F - 63,000 psi
Elongation – 400°F - 23%
Reduction of area – 400°F - 55%

I need to get the yield up to >68,500 - any suggestions how?

Thank you

 

[redpicker]

Do you have any flexibility in the material? You will get better results with heats that are higher in carbon and higher chrome and moly.

What material form are you using (bar, sheet, tube)? Timken has a material called Impact7 which should be available from warehouses in bar form. This may be up to the task.

 

[Macdost]

4130 was the first choice, again sour service, there was discussion about using 4140.

Do you think 4140 with similar heat treat as above; Water Quench – 1600°f - 5 hours, Temper – 1215°f - 6 hours, Hardness – 235 Bhn, will work?

 

[blacksmith37]

For thick sections you need 1 1/4 Cr : 1/2 Mo or 2 1/4 Cr : 1 Mo; These materials have been used many years for 6A / MR01-75. Very similar to T 95 casing ,etc.

 

[mfgenggear]

e link about material selection. good reading

https://pgjonline.com/2010/02/12/material-selection-for-sour-service-environment/

edit : why not oil quench instead of water quench ? less distortion , may be some of the experts can chime in

 

[Macdost]

Going to try a normalize, water quench, temper. Then going to try raising the austenitizing temp, temper. Then going to try a combination of the two.
Everyone I have spoken to in real life (not online) has said the quenchent would not make a specific difference in my situation.

mfgenggear - thank you for the link