next wed. we have to pump from a 32m into a 42m then pump an elevated deck. what is the best procedure to do this. should we just hook up the 32 to the 42m's pipe and do it like that, or should we just pump into the hopper of the 42.

i would also like to know. but take some pics if you can, would love to see them!

hey john our company tends to do the pump to pump a lot we have never done from boom to boom because we have big line pumps but the safest way is to plug into the deck pipe.

also this is a 5000 psi mix. it has 1750lbs of rock and 7 sacks of cement.

what would be the best way to prime?? a yard of grout?

whats the best way to clean the boom

how much pressure will be on the concrete? does my 1200 pump kit have enough to push it through my boom and the 42m

There are advantages to both the

pump into the others hopper and

plug into the deck pipe of the second pump

If you are pumping volatile concrete it is much faster and easier to get both machines clean if each of them has a full hopper and can either recirculate or suck a sponge. It is also the biggest mess and takes coordination and cooperation and good communication.

Pumping into the deck pipe is cleaner and easier to make the pour. Sucking a sponge is harder and sometimes takes a bit of air pressure while the other machine is pumping in reverse.

If you do the "plug into the deck pipe" program you need to think about the fact that the back end of the second pump is about 3,000 or more pounds lighter than usual. I would suggest filling the hopper with sand and water if you plan on reaching out over the front.

Either way THINK!

This is not an everyday deal and change creates safety concerns. ;~)

hey there johnthomas, i have done both ways. it depends on what equipement you have available on site and if you can blow the boom of the 42m out on the site. circulating should be possible if you are hooked into the deck pipe as long as you don't drain to much concrete out of the 42m boom, kink the hose and tie it off as kwick as possible, then swing the boom over the hopper of the 32m. unless your using extra pipeline you should reach. the best case senerio would be consistant delivery of mix, weall know how often that happens. if by chance you think that service will be interrupted, you might consider having 5 or 6 bags of cement powder in case you have to wash out and reprime, both or just the 42m. you 1200 kit in the 32m is ample to pump through both pumps.

Hi John,oh joy.Both ways has it's own problems but Bob had the best idea of sucking a hardball with a touch of air assist.Keep in mind a good blow out cap with dump valving for saftey.I cannot stress the importance of that issue along with good communication.I thought does not cut it there,you need to know exactly what is going on.I have an old friend in Atlanta with many years experience that was severly hurt because of a mistake with air blowout.

Very interesting with great information! I have to ask,  What is the safest way to pull this procedure off. Is to have great communication and just pump into the hopper? -3000 lbs of weight! That is good some facts Bob! I have pumped like this before it is messy but no one got hurt!

Whatever way works for you is the best.

Roy, I had, I am shamed to say, forgotten about David's accident; what a waste. Now there is a guy that knew about pumping concrete. With that in mind I want to say that all blowout caps are not created equal.

Every once in a while, when blowing out, the sponge will slap back against the blowout cap. (usually because the air is bypassing the sponge).... so you turn off the air, open the relief valve and either no-or a small bit of air comes out... or... the air is comming out and stops abuptly. CAUTION!!! this indicates that the sponge was pushed (WITH BYPASSED AIR PRESSURE) up against the air discharge port. If you take the clamp off you will get hit in the head by the clamp and either die or wish that you had.

REAL/professional air (or water) blow out caps have TWO SEPERATE PORTS one for input at the dead end of the cap; and one for bleed air positioned at least one foot (up-stream) from the end cap. The reason for this is if the sponge is driven back by bypass air it will go to the end cap and alow the bypassed air to continue to bleed from the system through the upstream discharge port.

MAN, THAT IS IMPORTANT!!!

If you are bleeding air out of a system and the air comes to a sudden stop you have a big ass problem!!! DO NOT OPEN ANY CLAMPS TO SEE WHAT IS GOING ON!!!

If you have a doubt about your blow out cap, or its use call CONFORM orACME AMERICA OR YOUR PUMP MANUFACTURER.

I know that many of you are sharper than I am, no question. Please get on this thread and let us know what you do to keep this from happening to you.

Thanks Manny for reminding me about this. This is, if not handled correctly, a sure trip to either the operating room or the morgue.

Please be careful; close is not for hand grenades or air pressure.