Have a customer that wants to pump a 50/50 exposed 2" minus 6 sac. Before I test pump it will it go? Thanks for your inputs/// 

What size is the line you will be using? Is the rock crushed or is it round such as river rock.

I'll take a stab at it and say it will pump. Two inch minus for exposed aggregate? Large rock requires less cement powder. It's the sand, and in particular the fine sands that contribute to surface area that must be covered by the cement/water paste. So if it is truly a 2" top-size and a six-sack (nearly 600 lb/yd) mix, then it should pump fine, especially if the course aggregate is round and not crushed.

It is a 32 M with 5 inch metric and it is crushed agg

Also color///

I'd run 5" as far as possible then reduce to 4".  Have em up the air entrainment as much as they can and slump will make a lot of difference.  I'd say its a 50/50 chance with my Schwing 750. LOL

I would think everything will be fine. The color will ad extra slickem. I was afraid you were going to try to use 3" hose.

I think it will go. Could you do a test at the plant yard?

You don't mention yardage or system.During the pour stay on top of it,color will accelerate the mix.Also this time of the year there using hot water,another accelerant.If it's straight powder,that's another accelerant.

So if the test pour goes ok,add system,all the makings of,oh joy.During your test try to watch the mud to see how it's setting.If it's flashing at the plant,you know what's coming on the job.

The short version

A little flyash would be nice as well especially if you've got more than 50ft of hose

There is no system, 15 ft exposed wall tip hose will be 4.5. also the rock will be blended 2' minus 3/4 minus 3/8s

will def test at the yard before the job. Has any one actually pumped this before?

PUT IT IN THE BIG END AND IT WILL COME OUT THE LITTLE END!  It sure looks like it has good gradiation/cement content-all the right goodies.  Just don't get stupid with the water.  John

HAVE PUMPED THE SAME MIX BACK IN THE 70'S WITH A 4" SQUEZZER, VERY SCARY, DID'NT BLOW A TUBE.  HAVE PUMPED RECENTLY WITH A SCHWING 1000 THROUGH 200' 4" PIPE 75' 4" HOSE NO PROBLEM IF THERE IS GOOD GRADATION.  REMEMBER WITH COLOR NO FLY ASH AND ADDING WATER CHANGES THE SHADE OF COLOR UNLESS ITS WHITE.  TRY TO GET SOME COLOR POWDER FOR YOUR SLURRY OR ELSE PRIME OUTSIDE OF AREA.  SLEEP WELL.

I honestly believe you will be fine,all good advice given.I did some scary stuff at noaa in Boulder years ago.It was 3/4 minus,the fines were crusher (red) with some color.It was all with a titan 3900,pluged at turret even with slurry.

Hence the term,"it's a concrete pump not a rock crusher"

Why in the world would anybody want 2 inch rock in a wall don't they have 3/4 rock or a smaller blended mix,when they take the forms off there will be lots of holes to fill.

It has the look the architect talked the client into. It will likely be juiced up with Super-P to get it to flow past the rebar. It's an exposed aggregate wall, eh? They'll strip it an sand-blast it, I suppose. Seriously, take a couple shots of the mud, pumping and after it's exposed. I'd like to see what it looks like.

Scares me that the 2" stuff comes rollin down the chute at the end of the load and chokes everything.  Architects

Yes it is a architech / Client thing going on, I will try to take pics, looks like spring or summer.

No problem.  Bigger rock is easier to pump especially since you are using 5 inch all the way.  I've pumped 2-1/2 inch rock before without issue and ACPA spec is up to 2/3 the size of the line, I think.

Be carefull of the Super-P though; if you get the mix too plastic(over 7 inch slump), it will separate and rock up easier because with big rock the cement moves past the rock easier.

Good luck and post some pics!