fuel return

I replaced the 3 fuel lines. 89 ram 50 I noticed that the return line pumps fuel back yo the tank is this normal? The return line comes off the tank right next to the main fuel line. The vent is the top of the tank correct? And the little check valve goes
To the vent line? So the return line is it supposed to dump fuel back to the tank at idle

That sounds correct to me. There also different sizes the big one is suction.