Seeking guidance....

[lkconcrete]

Hey everyone...was just surfin around and stumbled upon this site. I opperate a batch plant and drive a front dis for a precast company and have a few questions.

First, how do you keep the trucks so clean. The prob i am having is that our plant dusts a lil when the cement is being added, so any moisture that contacts the truck like rain or spash from the hose drys before wash at the end of our pour. Even if i rinse the dust off before pouring it still builds up over time.

Second, our batchplat is an older Ross setup. All manual. Agg and cememt are mixed in the truck. Probs I am am having sometimes are balling, and sometimes i will get batches that stick to the fins real bad. refered to as head pack???

Batch design is as folows:
Cement 640 p yard
3/4 rock 700 p yard
3/8 chip 600 p yard
Sand 1676 p yard

Chemical:
3oz air
76oz 555 plastisizer
fiber.

Water dependant on agg moisture content. All chemicals from Grace, mix is supposed to be semi SCC. In the past we had probs with water seperation due to not enough fine materials in the mix, though since we have upped the sand, i have not had many probs with seperation and bleed.

Sorry for my long newbie post! Any tips or thoughts would be greatly appreciated!

Thanks!

[Mort]

1. Constant washing. There's really no secret other than that.

2. I dunno. We wet batch, so unless we're not aligned properly (or the batchman pours it in too fast), its pretty clean. And what was the question?

Welcome aboard.

[BillyCement]

Get a long-handled brush and some cleaner. We used to use muriatic acid to clean the outside of the mixer. Now we use a non-acid based cleaner. I'm sure your employer has some kind of cleaner available. You've got to keep up with it every day or your truck will look 100 years old in a week.

[gant]

Learn your truck.. I know all the spots the cement and other aggregate likes to hide on my truck after I'm loaded.. I just in all the spots where everything likes to hide and rinse the fenders, drum, pedestal, wheels/tires, chute hopper, etc.. I just have a system that I use and it works.. also I try to wash my truck once a week with acid.. we're so busy that I havent had time and some ass-hole used all the acid.. this guy takes 45 min to wash his truck down after each job.. we call his truck the show truck...


about the balls and everything maybe slow down your load percentage.. I know they slowed the load down to 90% on my truck because it balls bad.. and our batch man holds out some water till the end to rinse down the fins for us..

[lkconcrete]

Would like to slow down the cem discharge from the batch plant, but it is auger fed and only has one speed. Tried reducing the pipe size where it comes out only to find it jams it up. Gonna try

I will have to get them to get some muriatic acid. We have a drum of HCL but it is a bit strong. Also tried some of that mud slide remover that worked pretty good. How are you applying the acid, with the brush or a sprayer?

[gant]

we have the drum of acid out by our 2" hose that we use to wash down our trucks and we have the acid and the fleet wash hooked up to a pump.. you can run just acid or both or just fleet wash and it comes out a sprayer

[lkconcrete]

Got the acid out on our older truck....starting to look better already.....

[db2179]

The batch balls can come from few things. We have a dry batch plant and have to slump our own loads if the batcher batches way to dry and you and alot of water to fast you get nothing but batchballs througout the load. As for cleaning your truck down time is cleaning time we also used to spray our boosters with form release but can't do it no more so now i will spray pam on thethe truoble spots on my truck when i no i have to run dirty.

[lkconcrete]

I tried using our form oil a few times though thought it made a mess so I stopped.

As far as the balls go, our mix is pretty wet with lots of plasticizer. I usually add 75-90% of the water first, then coarse aggs then the fines. In the last few days I have found that adding the cement later in the load has made less balls and less head pack. I started adding cem when almost 90% of my aggs were in.

[lafargeslave]

balling can also occur when the chemicals dont actually go into the load due to for instance running out of the stuff or the actuating valve not cycling and so none is dispenced. also some dry batches are not in the habit of putting in half the water first then the rest of the material. without having water in there first you run the risk of dry packing, which is worse than balling. at least balls come out of the truck. a drypack can stay in there for several loads before it breaks out. wet batches can also produce balling, although it is usually only with certain mixes or again a misbalance of the chemicals added.

[concretejoe]

There are many theories about the cement balls. You are never going to be able to eliminate them. You can help to reduce them by experimenting. You need to adjust your plant to how it runs. Every plant is different. They typical process should be as follows (10 yard load):
1). Water goes in with exception of about 20-50 gallons.
2). Agg starts
3). After about 2000lbs of agg then cement starts
4). Cement is completed with about 2-5,000lbs. of agg left
5). Remainder of agg goes in
6). Remainder of water goes in

Mix, serve at about 65 degrees.

I have found that this scenario helps to reduce the number of cement balls.

As far as cleaning the truck goes, try just using a wet brush throughout the day. You don't need acid all the time. Especially if it is recent.