overmetal tolerances

[Cmjfs]

Hello, I have a question to ask:
in one 6325-73 there are tables for the calculation of overmetals and tolerances for sand castings. I can't understand the meaning of "maximum size of crude jet"...that is: we decided that the class of tolerance for our piece (mode of a couple limiter joint) will be t6, or of the order tens of microns....so coincident with the nominal one??? ? I'm definitely wrong.....help! I'll attach the tables in question. . .

 

[meccanicamg]

T6? But how did you read the tables?
The letters are bc... you will have a few millimeters of overmetal not tenth.

If you have a finished casting it is 55 you will have that the nominal size is up to 80 while that of the crude jet below 120. then decide according to the accuracy to b or c.

cast.... size of the molten piece that will never be smaller than the finished, otherwise you have wrong the mold.

 

[SHIREN]

T6? But how did you read the tables?
The letters are bc... you will have a few millimeters of overmetal not tenth.

If you have a finished casting it is 55 you will have that the nominal size is up to 80 while that of the crude jet below 120. then decide according to the accuracy to b or c.

cast.... size of the molten piece that will never be smaller than the finished, otherwise you have wrong the mold.

hi ing
uhhaa is about models for foundry:tongue:
is exact the soo overmetals expressed in more mm
instead according to norm in case they are in zones with corners of browse the overmetal goes on increase the size

But even if there are tables, the overmetal indicates the foundry.
for the whole series of probes in which the rules are deficiencies the tables are only indicative
Thank you very much

 

[Er Presidente]

Hello, I have a question to ask:
in one 6325-73 there are tables for the calculation of overmetals and tolerances for sand castings. I can't understand the meaning of "maximum size of crude jet"...that is: we decided that the class of tolerance for our piece (mode of a couple limiter joint) will be t6, or of the order tens of microns....so coincident with the nominal one??? ? I'm definitely wrong.....help! I'll attach the tables in question. . .View attachment 28882
View attachment 28883

t6 is the tolerance of the finished piece not of the crude, which will have the size as table.

 

[Cmjfs]

thank you so much to all! I believe I have understood....to extinguish every doubt: So it can be said that in the event that the nominal size of my piece is 500, that of the crude will be between 500 and 1250 because it must be ever bigger?
already that there are I would take advantage of your availability x do another domandina.... regarding the connection rays of the crude how do I adjust?? Is there any particular rule?? ? thank you in advance and apologize for the stupid questions... .