Permissible out of roundness UG 80
Permissible out of roundness UG 80
(OP)
Hi,
As per UG 80(a)(1), difference between diameters shall not exceed 1% of nominal dia.then (a)(2) says when cross section passes through an opening or 1 ID of opening from center,difference may be increased to 2%. why this extra 1% is added and how does it make any difference? In what cases it is helpful)
Thanks.
As per UG 80(a)(1), difference between diameters shall not exceed 1% of nominal dia.then (a)(2) says when cross section passes through an opening or 1 ID of opening from center,difference may be increased to 2%. why this extra 1% is added and how does it make any difference? In what cases it is helpful)
Thanks.





RE: Permissible out of roundness UG 80
The Code recognizes this per (a)(2).
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: Permissible out of roundness UG 80
Hi lingeshgdvg,
Permissible out of roundness in above stated case is not 2% of nominal dia of vessel as stated in query.
As per UG-80 (a) (2)
"When the cross section passes through an opening or within 1 I.D. of the opening measured from the center of the opening, the permissible difference in inside diameters given above may be increased by 2% of the inside diameter of the opening".
That means total permissible out of roundness for above case = 1% of nominal dia of vessel + 2% ID of opening.
& for second question regarding additional tolerance I agree with SnTman.
RE: Permissible out of roundness UG 80
yes, only after submitting the question i realised that.