interpretation of MS33649 port drawing callout

[mikeyanxu]

Hello,

Need some help understanding a drawing callout of a hydraulic port.
Drawing callout is "PORT PER MS33649-05 MACH"
What does the "MACH" mean? Machined?

Thank you

 

[monkeydog]

Did you look at MS33649?

 

[mikeyanxu]

Absolutely. It is superseded by AS5202.
There is not a word about the callout "MACH".
I wonder if it is covered in ARP 4296 which is referenced on AS5202.
My company's cheapo IHS subscription doesn't include ARP4296.

 

[3DDave]

MACH is an abbreviation for 'machined.' Is this based on a casting?

 

[mikeyanxu]

Thank you.
No, it is not based on a casting or forging.
It is an end cap for an accumulator.

 

[monkeydog]

If you looked at the MS33649 specification you would have seen there are two types of bosses. A raised surface and recessed surface. Many people confuse the recessed surface as a machined port. I suspect that is what your case is.

 

[3DDave]

Is it still superseded by SAE AS5202 "Port or Fitting End, Internal Straight, Thread, Design Standard"? Looks like it is to me.

Probably it's a notation by someone who thought it meant something, but it doesn't appear as a modifier in the original or the replacement standard.