vac. pump on any tanker or not?

I would assume they would have to be built to handle vaccum on them, 8,000 gallons is ALOT for a vac trailer, I would assume you would have trouble finding them in that range.

A big vac tanker would be around 6300 gallons, 150bbls.

 

I've been inside a Heil straight round vac trailer, the top dome was centered and at the 1/4 area, one per end on opposite sides there were stifiners that looked like the solid outline of a dislexic leter D welded in place, it protruded about 10" - 12" into the tank to keep the vacuum from beer caning the tank..

You don't see anything like this in a DOT 406 or DOT 407 tanker. Pump those out with the dome closed and they will suck in!

Spec tanks are pressure vessels, they are designed to contain pressure not vacuum.

Vacuum dry bulkers are also structrually reinforced to handle vacuum and pressure.

You will find vacuums w/ out the pump [designed for tractor mounted units] and belly mounted and front mounted vacuum units driven w/ a diesel or a hydraulic system...all use a tank made for vacuum.

 

everything logan and wis said. i think the point to understand is that shell material/thickness has to be strong enough to defend against the vacuum trying to collapse it inwards. many perfectly good tankers have been destroyed (sucked in collapsed) as they were being off-loaded, without venting them.

 

Why so large? most are around 5000 - 6000 gal because building them larger means more engineering to prevent them from sucking in.

It is possible but may be so heavy that the extra payload doesn't matter.

 

At 8#/gal that's a 60K payload. A daycab w/ a PTO driven Dmag vac pump mounted is going to push 17K - 19K and a sleeper will run closer to 22K.

I doubt an 8000 gal vacuum would tare under 20K so you will be real close if not over 100K especially when you add in a few thousand pounds of slush/snow.