Hi, Everybody

well, yesterday I had 510 yards to pump. after all I got the job done but the pump took a beating. the first truck I primed  went pretty good second truck was the beginning . the deal was that the pump is not suking or pushing concrete . in my pump I have a switch normal, A, B I switched to A  didn't work I switched to B It worked  after 30 minute trying to push that concrete . then It would like ten strocks and skip one tell finish .

now I spoke to my friend operator for the 07 schwing they have nothing but schwing  6 of them well, he had the same problem that his pump was choking and he had to work with it pumping alittle at atime.

any idea?    I have pics of pump on job sites would like to post can anyone explaine to me how to do that?

Thanks in advance . 

I have had this problem in the past, not sure what it is with limestone itsegregates in the hopper and you cant get the conveying cylinders full. i ask the batchers to ver sand the mix that seems do the trick.Of corse at first the batcher says the computer says its a pumpable mix, i tell him to bring the computer to site and let the computer pump it..

Thats all we use here in florida the problem is most likely the rock it is a porous rock (has small holes in it) the rock must be sprayed with water for days prior to batching if not you will not be able to add enough water to make it pumpable because as soon as you pump it the water is forced into the rock leaving dry cement and sand to be pumped and we know that doesnt work to well. on the other hand you can also get it too wet. yep , thats right too wet. and youll struggle to pump that aswell.

Lots of limestone in Iowa. If thee material was not graded well it seemed to create more trouble than other types of rock. Bridging in the hopper was common. The problem was getting the cylinders to load. You spend lots of time with the agitator in reverse. Some of the trouble came from the rm trucks, or procedure. Mix the load after getting it to the correct slump, mix it fast and then stop the drum, no slow mixing. When it is time to discharge the truck - do so. Sometimes you will need to stop about 1/2 way through and repeat the program.

Good luck... and don't raise hell with the concrete guys, the problem comes from the quarry.

Thats right, the concrete supplyer is trying to go cheap I always pumped there concrete but now that all the concrete supplyers are combeating on thier prices so gus what they sell you the uglyiest material

Also, Schwings with accumulators throw so fast they wont burp air like they should! I find that if it starts missing a stroke,wait for the next missing stroke to finish,then back up one stroke.If it burps and changes tempo, like a previous post said, reverse your agitator, then see what happens!

Don´t the RM mix the load in full speed atleast 1 min before unloading in the pump ?

They are told to do that when they revers to the pump or when they see that they are next on deck...

All mixers should do it that drive for the company I work for....But do they ?