Dear all,

Is there any limitation for max. hub thickness allowed for self reinforced nozzles with reference to shell thickness?
(As per shell DEP std, max hub thickness is limited to 2 times of shell thickness.)



Regards
Vgsh

_________________
Vijeesh

No, but it is useless to put material outside the limit where material can be used for reinforcement.
MG

Dear Mr Gonzaga

Thank you for your reply.
Here one of our nozzle (30") is not getting passed because the stress ratio is >1.
Shell thickness is 80mm & hub thickness is 160mm.
Am asking about can i increase the hub thickness further more. Is there any limitation for this thickness compared to shell thickness?

Thanking you in advance.

Vgsh

VGSH

There are some doubts in your problem.

Which stress ratio is more than one ? If it is 3S limit there is some probability that decreasing hub thickness can help? Are you talking about pressure loading or nozzle loading? What is the stress that exceeds (membrane or bending) and at which location?

What about putting a pad or insert plate for shell? More detailed information including temperature and material can help to suggest solution.

If you analyse for thermal loading, you may find stresses increase with thickness also.

Please provide more details for further discussions

Regards

_________________
R.SRINIVASAN
Sr. VICE PRESIDENT
Head, Design and Engineering
PED,ISGEC,
YAMUNANAGAR
HARYANA -135001
INDIA

Dear Mr Srinivasan

I was talking about the nozzle loading.
The nozzle size is revised and hence the problem is solved.
Thanks for your valuable effort & information

Regards
Vgsh