ASTM A815 - Table 4 - Tolerances?

[Joe20]

Hello All,

I am not a engineer, but a purchaser of steel pipe and fittings. I want to ask the experts out there a question pertaining to common ASTM practices.

I had a metal fabricator create several swage nipples from round bar, material S32750. The round bar (raw material) MTR lists the tensile strength as 115,748 KSI. This is slightly below the minimum of 116,000 KSI for ASTM A815, Table 4. My customer's engineer is giving me a hard time about this reading on the MTR.

• In your experience, are the ASTM minimums and maximums hard numbers, or is there a +/- tolerance?
• Or is every ASTM standard different?

I have attached Table 4 as a JPG for review.

Any help would be most appreciated!

 

[ajh1]

ASTM standards generally consider yield and tensile stresses to be rounded to the nearest ksi, so your 115,748 would round to 116 ksi and would meet the criteria in the standard (barely). Watch your units. You do NOT have 115,748 ksi, but rather psi.

 

[Joe20]

Thank you for this information and for informing me of wrong unit of measurement!

My customers are mainly in South America. Where we use a period between whole numbers and decimal places, they use commas. And vice versa. So, the 115,748 KSI for them is the same as 115.748 KSI for us. I should have clarified as such.

Thank you again!

 

[CoryPad]

Significant digits is covered by ASTM E29 Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications. The result meets the requirement.

 

[EdStainless]

There are rules for tolerances on values as far as decimal places, but yes your value would round OK.
But if you had parts forged then they should have been reheat treated, and then retested.


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