Dry concrete in Redi-mix truck

make sure you have the key and signs stating you are working in there. A guy got killed just before I went to work at one company. They can be razor sharp. I had a mixer that was specialized for mixing grout. Concrete would stick to the specialized fins. Fall off when I put the admix in for pump crete, land on the pump screen.

You can "rock it out" Have them load it with rock only and spin it and empty it.
Wash the fins really good when washing out.

 

I forgot about the rock out method A+++ way to do it without crawling in and sweating it out.

 

if you spray out the fins good after every unload, then about a wheelbarrow full a year. if you are lazy with the hose, a yard every couple months.

it is WAY easier to spray a hose, than hammer a drum.

i have seen men with trucks that wouldn't hold a full load, because of the built up concrete in the drum. those fellows should be fired.

 

Uh, I worked for a Concrete, Aggregate, Excavating, and Underground company for a decade ... Drove a mixer for a few years solid. My personal truck, I would hop in the drum and chip it out twice a year ... and get maybe, MAYBE a wheel barrow or at most a 1/4 to 1/2 yard out of it (which was always up front where I couldnt get to when washing down). Did this is in Arizona, where heat is definitely an issue curing your load on a job site. And I was one of the chosen few that had to run lots of low slump "go off in the drum" chemicaled loads.

We had 2'' wash hoses after our batch plant. It was standard practice to batch stiff, and have the driver adjust the slump. This allowed us to hose off the back fins right after being batched (dry batch). When done at the job site, I would climb the ladder, wash down the charge hopper, discharge hopper, and every fin I could see. If there was any clingers ... I would do my best to dislodge them. Always used a brush to clean my chutes ... every time. If I was stuck on a job site for an extend period of time. I would clean em up to keep from having to chip the chutes later. If I emptied out at the job site, I'd always open up the add water line and fill the drum with water, and run it out when I got back to the plant (would do the same if I knew we were trashing whatever was left in the truck).

I always kept the truck clean ... its easy to keep it clean, really difficult to get a handle on it after it gets out of control.

If you get a load of shotcrete, powder gunite, or have a load that goes off in the drum ... or just as a maintenance thing (if you cant keep build up in the drum under control) you can have the batch man run 5000lbs of 3/4 in dry rock into the truck, let it tumble for a half hour (run it to the back and front a few times too) ... that will grind off build up if needed.

 

The problem is when you get a dry load like curb mud and they take a long time to unload, and then use most of your water before you realize it, thats what mucks up the fins.
The first time I climbed through "the hole" I said "oh crap" but once you are inside its not too bad. Actually if you get in there every couple of weeks and beat the fins with a big hammer you can keep on top of it. Of course once build up starts, it kind of perpetuates itself, concrete sticks to itself better then a slick metal fin.
Flowable fill was the loads I liked the best, slop it up real good and let it fly, and easy cleanup.
Concrete truck was my first trucking job, but since moved on to precast concrete products.

 

I drove cemet truck for 5 years. We never had to chip out our drums. The owners hired a company to do it. 3 yards is a lot. since most trucks here are now 10 to 10 1/2 yards. I had a old mack that was 11 1/2 yards. What we did here was dam near filled the drum with water. if you had any left over at the end of the day. all that water will seprate the concrete. We go to the waste area and spin the drum and all the crap will come out. then we dump the water in the water tank and spun that out. The drum will be clean. our trucks can go a year without being chip out doing that way.

 

Yeah like the others have said already, making sure your washing down the fins really good after getting loaded and keeping on top of it and washing up all the fins after getting unloaded. You can usually get a good angle by holding the hose at the bottom part of the drum and spraying up into the fins that way it falls off and you can hit the back fins better. The first time I started to climb into the drum I got all scared thinking it was gonna be that tight all the way back, but once you get all the way in you can stand up in the back and start whacking away. But once you get loads like I've had the last two days, 7 loads of 1.5 inch slump curb mix for a curb machine it starts to build up on the back of the fins then after that it builds up no matter how good you wash down. Also its real fun when you get a load of well grout, just water and cement, now that will build up the fins bad. That curb mix is crap, have to have the drum on full discharge and splash the water every 10 or 15 seconds for it to even come out of the truck. Also when chipping you gotta find that sweet spot on the fin with the hammer, you start hitting the part of the fin on the corner where it starts to go straight and the stuff falls right off. Also it's best to do it when the drum is dry, lots of dust but if its wet then you come out looking like you were mud wrestling.

 

Yes this is a must, your company should have a kit that has two signs. One goes on the steering wheel, and one goes on the door that says man in drum. Also either put the keys to the truck in your pocket, or give them to the batchman. Also make sure you depressurize your water tank so one of the other drivers that likes to play jokes doesn't come by and turn your water on ya while you're in the drum.

 

Hydrochloric acid works wonders......But you have to be careful.....It will etch the drum...

 

that what we had was acid. it does work wonder. When it comes to chipping. One guy has to be outside of the drum with the keys in his pocket making sure no one try to start the truck. The good thing. our company hire out to have the drum chip.