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Which concrete pump?
The Basics
I include more detailed information to inform you about your choice on my waterproof concrete page here.
The cheapest to hire is very often a 4" line pump. You can haul the end around. It takes 3 men just to move it. You can remove sections to make it shorter but you have to drag it side to side as you progress. The end full of concrete weighs about 100kgs, so you cannot pick it up. The thick pipe is very resistant to being bent into a curve. Bending it can require 4 or 5 men. A line pump and 5 extra men might make it the most expensive option.
It depends on how many relatives will work for free and whether they will ever help you out again.
It starts off deceptively easy.
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But it soon becomes a continuous struggle.
Too much here. Not enough there.
A line pump usually comes with a mix of steel pipes, rubber pipes and bends to pump 30m. They will bring more if you order and pay for more.
Never use a line pump unless you have no choice. And never for walls.
These are boom pumps. They do most of the work for you. They cost the most to hire but you save on labour.
A word about what size boom pump you will need.
The pump in the photo above is a 42m pump if you measure 42m from the ground beneath the truck to the tip of the double bend when the boom is straight up in the air.
This means it won't reach 42m.
First, it articulates almost 4m from the ground. Leaving 38m.
And it must set up its outrigger before it can raise its boom. Another 4m lost from the start of the boom to the tip of outrigger. Leaving 34m.
Finally, the outrigger must be a safe distance from any excavation. This might be another 2m. Its reach beyond the edge of the excavation, in this case, is not 42m but 32m.
You might find that a 32m pump is a reasonable cost but a 42m pump beyond your budget and expectation.
Common sizes would be 16m, 20m, 24m, 28m, 32m, 36m, 42m, 52m, 62m and Camfaud have a 72m. I list most suppliers at the bottom of this page.
Your pour might be so small, and the concrete delivery truck able to get close enough, that you don't need a pump. Just the delivery truck chute and perhaps a bit more chute you make up on site.
But either will leave you with quite a lot of raking by hand. Increasing labour costs to have enough people to complete the raking in good time.
The cost of getting concrete to where it is needed, compacted and finished, in good time before the concrete begins to set, is a combination of labour and pump.
Arranging your concrete, concrete pump, and labour, to complete the pour quickly, can mean more men paid a full day but who only work hard half a day before the work is done.
In my opinion this is wasteful on a domestic site.
Different on a big commercial project where they can be pulled off something else they are doing and return to it in the afternoon.
The best of all worlds would be a pump that costs a bit less than the boom and might not need more than 2 people.
The worst would be the concrete going too stiff before your team had it in place and nicely finished - and you had to hammer it out where it was wrong, throw away concrete and steel, and replace it costing another day of plant, of labour, as well as materials.
Mixamate have pumping mixer trucks. I go into more detail on the page about waterproof concrete here. The Mixamate lines are only 3" diameter. A lot lighter and more flexible.
If you only have one truck, it is mixing for 6 minutes then pumping for 6 minutes, giving two men 6 minutes to spread and finish what just arrived before more comes out. If you have 2 trucks, they pump alternately but after 17m³ they will both be empty and you have a while to get the finish you want before more concrete arrives.
I go into more detail on the waterproof concrete page.
These same two men filled their walls on their own. The wife didn't stand around in pink boots that time.
They chose Mixamate, a Mixamate pump, and a boom pump as well. But no additional labour.
Pomphrett, 13 in the list below, have a particularly good flexible tremmie pipe that threads between the two faces of steel reinforcement allowing the concrete to trickle continually to the bottom without spraying off obstructions, and at a manageable rate.
To fill walls properly, you need the boom overhead and you need to lower the rubber pipe a short way between your layers of wall steel reinforcement. That is necessary to shoot the concrete between the steel to the bottom rather than pouring against the steel which will spray concrete in every direction and you will only get stones at the bottom. That is called honeycombing and it will leak.
These are the numbers I have stored in my phone.
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