i got a situation here, where my nozzle allowables are zero and there is no thermal displacements. I brought the allowables to 5 kg in sustained and 50 kgs in operating & design, but the seismic goes to 80 kgs. is there any way one can get to 0 kgs or near.

please provide a solution...

I am new to this forum. about me- iam a young engineer of 23 yrs.

What size are your nozzles? What are you connecting to? What code are you designing to? What is the contained fluid? What are your design conditions?

In general, you will not be able to get your nozzle reactions to "zero." Most equipment vendors today will give you real limits for loads, although they may still be difficult to meet.

If your pressures/temperatures are within reasonable limits, you may be able to place a metal bellows or rubber expansion joint at the connection and effectively produze "zero" piping loads. Pressure balanced expansion joints are also available, although considerably more expensive. They can come closer to "zero" loads.

You might also want to look at NEMA SM-23 for a discussion on allowable forces and moments on steam turbines, or API-610 for pumps. WRC-105 is a tool for calculating stresses in nozzles on cylindrical tanks that is useful for many applications.

You should send a formal request to your equipment vendor for approval of the forces and moments you have calculated with your latest run. Note that in many cases, moments are more critical than forces at terminal connections. You should include calculated moments in your rrequest to the vendor.

Use the [Search] option above to search this forum. You'll find a number of posts discuss this topic. These are particularly enlightning:

http://www.coade.com/cgi-local/ultimatebb.cgi?ubb=get_topic;f=1;t=001431#000000

http://www.coade.com/cgi-local/ultimatebb.cgi?ubb=get_topic;f=1;t=001325#000000

http://www.coade.com/cgi-local/ultimatebb.cgi?ubb=get_topic;f=1;t=001252#000013

http://www.coade.com/cgi-local/ultimatebb.cgi?ubb=get_topic;f=1;t=000895#000004

Mr.Craig:What size are your nozzles? What are you connecting to? What code are you designing to? What is the contained fluid? What are your design conditions?

8" Nozzle, connecting to Gland seal condenser, code: B 31.1 and the fluid is condensate at 100 deg celcius.

thanks for your reply. as U have said, i have sent the loads for the approval for the approval with the last run. The moments are like 50 kg.m

they have said no for using expansion joints, it would be more costly. I have used the advantage in the routing now to bring it down to this limit.