Pumped my first load of 1.5 " stone today after three years with my machine. I was wondering if there is any difference in ware factor compared to 3/4 stone?

Thanks,

Seed

good question I just started a job with all 1 1/2 inch aggregate I think the wear factor would be a little higher

Most definitely there will be a higher wear factor especially if you have corse sand....

I have found that if the proportions/grading are correct that it is easier to pump. Less surface area to cover + overall grading is usually improved. Pressures should go down, not up.

While pumping 'non spec' mix on a nuclear job we would sometimes ask the plant to replace 150# of 3/4" with the same ammount of 1 1/2" to make the mud easier to pump.

I guess it depends on the type of rock. The limestone I pumped in Houston back in the day was pretty tough on teh pipeline, grate, hopper, skin....whatever it touched

There was 3/4 blend is this stuff. It pumped great! How much more ware could there be? For example 30,000  yard pipe ware with 1.5 Agg is what?  25,000 yard pipe?  

WEAR is determined by the gradation of the fines usually, the size of the large aggregate,(stone), doesn't because if it is a pumpable mix, the fines should cover and suspend the stone. Bob is right though about PUMPABILITY being enhanced when there is a blend of different size stones. 

good question seed.  the big booms out here seem to see 1 /12 once in a while.  i thought that big rock is cheaper put in a cheap 'pumpable' mix.   

So it is the sand that wares the pipe?

Yes it is the sand, the cement and the fly ash that produce the most wear.

Nice schooling Captain Vic! Thanks!

Seed,

There are just a few factors in the what wears out my pipes category.

1.     The velocity of the material in the pipes – more speed = more pressure

SPEED KILLS

2.   The hardness of the fine aggregate. For a good understanding of this part of the problem go to Google and enter

Mohs scale of material hardness.

" Speed Kills " I guess the faster we pump the more we have to charge!

Thanks everyone!

Seed,

The 'yardage' charge does charge more for pumping faster.

Simple math - bad example, but you get the idea

1 hour pumping @  $100.00 per hour

=$100.00

***********************

1 hour pumping @ $95.00 per hour + $1.00 per yard = $100.00 @5yph

@100yph the hour cost the customer

$195.00. You are paid more to pump fast

ps - just an example, the above prices are WAY LOW ;~)