One of our concrete supervisors who is over our flatwork crews that looks at jobs and goes out with the pump and crews and keeps the pours going, backs in trucks, keeps the slump consistent, and wheather he knows it or not does a great job.

Doing 3 inch lines jobs off the end of the boom, He believes that placing a rubber hose between the tip 90 and the reducers lessens the chances of plugging

What do yall think?

Pour It Out Tink Burns ; )

Realistically it may be true.I would say mixes plays a roll.wouldn't you? I mean a good mix and the reducer tends to stay full more.It may be worth a chance to play it both ways just for grins,recording the outcome.

I have done it both ways seems to be 6 one way 1/2 dozen the other,if hes doin a good job humor him I dont think it will hurt you either way unless a weak hose shows itself on a plug but in the end its one more piece of larger line before a reducer cuttin down on your smaller line but to me its what makes your job easier and keeps him happy and feeling important.

I always like to use short rubber line between the tip and smaller size reducers, that way if you do plug (which will most likely be in the reducer) you can disconnect and pinch off the rubber line from the boom while dealing with the plug, then when you go to reconnect your system you do not have a flow of concrete draining from the boom to get in the way/create a mess.....

i run 4in off my boom if they wont to go down to 3in 5/4 off the boom 1or2 of 4in then down to3.pray for grout pump on slow..if we are pooring a pan deck in side.

always put a 5 inch off the boom and then reducer. just seem eaiser if something happens and to move around :)

16 cell thats a good idea about pinching off the hose. Otherwise you have to drain down the pipes on the floor. Last week I had two plugs in the 2.5" and yes i had to wait for the drainage and mess.

thanks for the replys, but, no answer to my question,,,    does the hose reduce the chance of plugs?

reduce the chances of a plug, i can not think of a single reason why it would.  it could have other benefits, id like to hear what your guy has to say.

No, the internal friction factor of a hose is approx 3 times greater than steel.

if you are running a 5/5.5" boom line then you would probably be overloading the boom by adding a full flexible then a reducer then your 3 "flexis.  A hanging reducer is always easier to prime thru tho, even on a pipeline.

 The only thing that reduces the tendancy to plug is the mix. As a rule when Im down to 3" it is a peagravel 3/4- mix and, it is wetter, wether with plasticizer or, water. I prefer the platicizer. Also I like to add a screen on my hopper grate to keep the nasties out. This is especially true here since they are starting to use hotwater mix and, the fin chaff pops off for the first couple of weeks. I have had drivers try and, pull off the screen and, we have gone round and, round over it. I use the standard garden fencing for a screen and, havent had a single plug using it.  

It's alot easier to prime through a bigger hose, and like 16 CELL said, cleaner if you plug.
I like to prime through a 4-5" and then hook it up to a 2.5-3", mainly because my aircuff is that size.
But it's just another case of 'See what you get and take it from there'.

hey to flat change your colors cant read them replys

 Since a rubber hose creates more friction it draws more fines or cream to the interior walls than steel. Which would make the concrete more consistant just before it's reduced. Makes sense so I'd say 'yes' it probably helps.

Anybody who answered that question, except murf, had better not bash anybody on this site for running double ended hoses, swinging trusses etc.  Its a moot point what it does the one certain thing is you have exceeded the permissible working weight no matter what make of machine.  If plugs are that big of a problem use a larger diameter hose.

granddad not sure where your coming from?  nobody mentioned lifting the reducers attached the the double ended hose.  you are correct, i didn't read it being suggested in this discusion...

hey TooTall, long time no hear. 

Grandad, the hose is used for connecting to smaller reducers eg. 3-2.5/2.5-2 which are laid flat on the ground and not supported by the boom, the weight of a 5-4, 4-3, and a short double ended hose is well within the manufacturers specs.... From what you are saying the only other way to do it would be to hang several consecutive reducers from the boom (which would be same same weight as less reducers and a short connecting hose)... or I suppose the last option is running X amount of 5 inch line... which is unheard of on 95% the the pours in our region, as we are fortunate to have some "small line friendly" mixes up here

just to clarify... 5-4 reducer 55lbs., 4-3 reducer 40lbs. 6 foot double ended 3 inch hose 80lbs., (all weights are for said items filled with concrete) and 30lbs. in clamps... Total weight-205lbs. even our 40M Putz. (which is one of the most severely weight restricted booms out there) has a load rating of 210lbs..

Be carfull cause hoses absorb moisture from the mud more than steel pipe so to much rubber can dry out the mud and cause you to plug. The less you hang off the end of your boom the safer it is.

very friendly small line mixes out here.  75% of my line jobs are 3" hoses off the boom.  not such an issue now, there is no way my back and the concrete gangs backs can take 3.5" - 4" hoses day in and out.  if we are useing pipe, 5".  get great 2" and 2.5" line mixes off the boom as well.  i try and use one size of hose to reach the job if possible.  

love Ocean out here. delivers some very nice, very pumpable concrete mixs.  just wish they would type on the bill the ratio of rock, sand, cement and additives instead of keeping it a secret.