LPG Pipeline Size Calculation

Dear All,

Greetings of the day,

I have few queries on LPG cylinder/vessel installations at industrial customer location.

1.How to calculate the Liquid LPG Pipeline size?

2. How to calculate the Vapour LPG pipeline size?

3. What should be the maximum velocity of liquid and Vapour LPG inside a pipeline ? there various data on net saying, for liquid and vapour LPG the velocity should not exceed 2 & 9 m/s respectively. But i want to know, where the same has been written, any specific code or book which says the same .

it would be a great help if you all could through some light on the above request.

regards,

Iqbal