Jim_CMG
Industrial
- Oct 30, 2022
- 1
We are looking to produce a simple hex nut (1-1/2" hex); however there is difference of opinions regarding the proper material choice.
I would appreciate your opinions.
(The print date is 1986, if anyone finds that informative.)
The material note on the part print states ...
Material:
Carbon Steel, SAE J995,
Rockwell B91 MIN
Rockwell C32 MAX
We find in the SAE J995 specification, under Section 4. Material: (snip attachment)
"Nuts shall be made from steel conforming to the chemical composition limits specified in Table 1:"
What concerns us in Table 1 is the MAX sulfur.
Grades 2 & 5 specify 0.15 MAX. (The print does not specify a grade to produce to, just hardness.)
We also have Note 2 that states:
"Resulfurized and rephosphorized material is not subject to rejection based on check analysis for sulfur." (underline added)
Where this note applies creates a bit of confusion.
In the table we find it attached to MAX Phosphorus in Grade 2, but not to Sulfur. (see attachment)
How should we understand and apply this to our Sulfur content?
Our problem:
We have identified A311 Class B (1144 Stressproof®) as a potential material. This is a resulfurized steel produced with a hardness within the specified range.
However, the sulfur range is 0.24-0.33.
My question(s):
Does J995 Note 2 allow for the use of A311 Class B material?
How does the J995 Note 2 specification of 'Check Analysis' inform our application of the note?
[vs the Heat Analysis (Ladle Analysis) certification of the material.]
One of our camps hold that Note 2 allows A311 class B ... the other does not - pointing the the ladle vs check analysis criteria.
Our other option seems to be limited to using 1045 bar with heat treating.
(Lot size is less than 5,000. Produced from bar product on a CNC lathe.)
Your thoughts are appreciated.
Thank you for your time.
Jim
I would appreciate your opinions.
(The print date is 1986, if anyone finds that informative.)
The material note on the part print states ...
Material:
Carbon Steel, SAE J995,
Rockwell B91 MIN
Rockwell C32 MAX
We find in the SAE J995 specification, under Section 4. Material: (snip attachment)
"Nuts shall be made from steel conforming to the chemical composition limits specified in Table 1:"
What concerns us in Table 1 is the MAX sulfur.
Grades 2 & 5 specify 0.15 MAX. (The print does not specify a grade to produce to, just hardness.)
We also have Note 2 that states:
"Resulfurized and rephosphorized material is not subject to rejection based on check analysis for sulfur." (underline added)
Where this note applies creates a bit of confusion.
In the table we find it attached to MAX Phosphorus in Grade 2, but not to Sulfur. (see attachment)
How should we understand and apply this to our Sulfur content?
Our problem:
We have identified A311 Class B (1144 Stressproof®) as a potential material. This is a resulfurized steel produced with a hardness within the specified range.
However, the sulfur range is 0.24-0.33.
My question(s):
Does J995 Note 2 allow for the use of A311 Class B material?
How does the J995 Note 2 specification of 'Check Analysis' inform our application of the note?
[vs the Heat Analysis (Ladle Analysis) certification of the material.]
One of our camps hold that Note 2 allows A311 class B ... the other does not - pointing the the ladle vs check analysis criteria.
Our other option seems to be limited to using 1045 bar with heat treating.
(Lot size is less than 5,000. Produced from bar product on a CNC lathe.)
Your thoughts are appreciated.
Thank you for your time.
Jim