"shantia" wrote in message
...
what is unclear?!
as I said , its a turbine part , so tolerances are strict , if you
need it , the deviation in diameter is not more than 0.15 mm in 1860
mm , in inch :0.006 inch in 73 inch
is it clear now?

I re-thought this because something has been nagging at me. Because you said
"sheet" I've been thinking in terms of plate. This isn't a plate-rolling
job. It's a ring-forging job.

It could be ring-forged and then machined. You'd have to start with a
complete ring but you'd have a fairly low-stress part after machining. Then
you might be able to achieve your tolerances.

Search on "ring forging." I think you'll find what you're looking for. You
might even make your projected cost.

Sorry I floundered around on this. I usually can identify the process needed
for doing odd jobs, after decades of reporting on practically the whole
metalworking field, but sometimes we trap ourselves into one line of
thinking when we should be looking at another. Once I thought of it as a
complete ring, it jarred my thinking.

This job is right up the alley for ring-forging.

--
Ed Huntress