It's raining in the lab

Published: Tue, 10/29/13

"John, I was first team All-State. I can put the ball anywhere
I want to. I'll make it rain out here."
- Jeremy Grey in Wedding Crashers (played by Vince Vaughn)

We recently had a big snow here in beautiful Butte, America.

We're at a mile high, so we should expect nasty weather, right?

Anyway, it's also raining here in the lab.

Well, not actual wet rain.

It's raining sand.

Yes, my friend. Sand.

I've been doing a lot of crush tests lately.

Part of the process is loading the crush cell (it's a small but
heavy cup-like cylinder of steel) with an even layer of sand in the
bottom.

Then you put the piston in (a heavy solid cylinder of steel that
fits perfectly into the crush cell), that rests on the
"disc" of sand, and you crush in a hydraulic press.

Here's the deal: that top of the sand "disc" needs
to be as smooth and as even as possible.

That's where my pluviator comes in.

The pluviator is a neat device made by Paragon machine company.

Your pour the sand in the top of it, after you assemble the pieces.

The assembly rests on top of the crush cell, like a little tower.

The sand then "rains" through two mesh screens, causing
it to fall in a distributed shower through the tower.

This nice shower of sand creates a perfectly level disc of sand in
the bottom of the load cell.

Now we can be sure that each crush test compares "apples to
apples" with the same flat surface of sand.

It takes a bit more time and effort, but the crush tests come out
very close to each other.

For instance, I will often do a crush 3 times at one pressure, and
then average the percent fines produced.

Most of the time, these separate crushes result in very similar
results.

I really believe that has a lot to do with the pluviator
"making it rain."

If you want to have the pluviator make your sand rain, and see
whether or not your sand has a high enough crush resistance to be
frac sand, then head here:
http://www.globalenergylaboratories.com/