Basic question: Can I connect 300# nozzle with a 150# line?

Hi experienced guys, I mean, everyone (everyone has more experience than me)

I have an exercise where a 300# vessel nozzle has to be connected to a 150# pipeline.
Can I do this in real world?
I mean, my pipeline has all components (valves and flanges, etc) with rating 150# but when it reachs the vessel I need a 300# flange to connect to this nozzle. Is that right?

Thank you.

Thank you so much.
So a vessel nozzle and a flange with different rating I can connect , but can I connect, for example, a 150# flange with a 300# flange?
I've checked flange tables and I realized the outside diameter and number of bolts for a certain diameter are different. Then, I conclude we cannot connect them. Is that right?

Thank you again.

Thank you so much.
So a vessel nozzle and a flange with different rating I can connect , but can I connect, for example, a 150# flange with a 300# flange?
I've checked flange tables and I realized the outside diameter and number of bolts for a certain diameter are different. Then, I conclude we cannot connect them. Is that right?

Thank you again.

That is correct, a Class 150 flange will not match up with a Class 300. You need to match the tank nozzle with a Class 300 flange. It is usually allowable to go up in flange rating, but I would be curious on why the vessel has a rating requiring Class 300 and the connecting piping is only rated for Class 150.

Thanks a lot again.
No, no. I am not planning to connect 300# vessel to a 150# pipe. This just coming from my confuse student mind.
Thank you again.

Hi...if you have an idea about the P and ID a 300# vessel nozzle must be connected to a 300# line also. If there is a case that there are two different ratings, u need to verify if the line or the nozzle is correct. Check the consistencies of both side.