Water cooled evaporator

Dear Guys,

I have a question, at DX evaporators with for example R22, liquid of R22 after passing form expansion valve device enters to evaporator and ….. finally we join suction line to bottom of suction collector.
Suction line must joint to bottom of suction collector to carry oil by suction line.
Attachment 14613

But at any water cooled DX evaporators, liquid of R22 enter form bottom of evaporator and gas comes out from top. In this case how oil is carried by gas ? oil prefer to comes down but our suction line is at top !
Maybe you tell suction line can carry oil as result of high pressure of suction line, In some cases we have water cooled evaporators for sub-zero systems and sub-zero chillers. Twice with low suction pressure how oil comes back to compressor ?

Sincerely yours.


Attachment 14614