PIPING DESIGN VS OPERATION AND PROJECT COST

[franky]

What is your preference, when you make a project and you have to install manual valve and check valve at a pump discharge. Will you prefer to install it before you increase to the line size or after? Before means to increase your operation cost due to increase of pressure drop and premature usage of your seat or after meaning a bigger valve and higher cost on the project.

I will like to receive your preferance and what will be the exception and at wich size you will thing to save money on your project cost.

Thanks to everyone, who will participate to this debate !!