[hc]

Hey Boss,
I will attach some helpful links. I’ve been designing rail loading/offloading facilities for the past year so I’ve probably gone through alot of what your going through looking for answers. To offload from the bottom of rail is pretty easy. There’s a valve on the bottom of the railcar with a threaded plug. The plug gets removed and a connector similar to the dixon valve connector (see link) is attached to the rail car valve. A hose connection or loading arm connection is attached to the dixon valve. The hose is attached to your pump suction assembly. A moveable drip pan is placed under the rail car (or a permanent solution is installed) bottom valve to catch any leakage. Once everything is connected, you can open the valve on the railcar and the valve on the dixon valve connector and product can flow.
Hopefully that helps.
HC

Rail valve connector: https://www.dixonvalve.com/product/ATC40ASSAPI
Helpful video]http://www.youtube.com/watch?v=mwh3601eGKA[/url]