Volumetric vs. Gravimetric filling

[rhodie]

Or rather, stated in other terms consider filling by volume versus filling by weight:

What are the advantages and disadvantages to each? I suspect it is a cost/accuracy dilemma.

 

[BLN]

I know from our manufacturing floor, it's a lot easier to measure weight than volume for high speed manufacturing.

 

[aspearin1]

There is also the whole temperature control dilemma. Density of a fluid decreases as temperature increases. If you don't keep your fluid temperature controlled, the amount of material in your outgoing packages can vary widely. Your company could consistently be losing money and/or scamming the customer. Consider also if you have an extremely viscous fluid with entrapped air. Volumetrically, you may have the same as a fluid with no air, but if you packaged it volumetrically, then your customer would be paying for all those air bubbles. If packaged by mass, the mass of entrained air would be negligible. From a process stand-point, if using an automated system, a packaging operation based on mass could be programmed to shut off or slow down once a certain numerical value where reached. Volumetrically, you'd have to rely on a float valve or electronic eye to scan when a certain volume were reached. The accuracy of this decreases exponentially with greater diameter packages. (who's getting scammed now?)
If you're talking about packaging of solids... Again I say, why pay for all that air? It's clear to me that packaging by mass is superior. (Tell that to your gas station.)

aspearin1