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8mm to 6mm?

[emoji23][emoji23] i had the latest van done up by the shop and didn't realise they put 8mm instead of the 6mm I got on other... [emoji23][emoji23] MASSIVE difference!! stay away from 8mm.. for the reasons above [emoji1312][emoji1312]and more!

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Morning all, I have recently changed my reel hose from 8mm to 6mm , its lighter, more flexible and a lot easier to wind in.Have any of you switched and did you have any problems with pressure etc?

Many thanks

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That's interesting to know. I have always used the 8mm and wondered if there was much of a difference in performance and use between the two. I have also been considering buying the electric PowerUp HD reel from Waterworks but the HD reel only takes 100m of 6mm and not the 8mm, so I would have to buy new hose to go on it, then change all my connections. However the 8mm hose will fit on the regular PowerUp reel (Cloverleaf) model.

I was curious to know if there was any pressure difference between the two diameters of hose. I haven't switched yet but its looking like ill have to if I want the PowerUp HD reel ....and if its quite a bit lighter, easier to work with, that may tip the balance.

Ta for sharing the info that you have discovered.

 
just changed all mine from 8ml -5ml and I sat and worked out that we would be around 27% down on the flow rate so we now run on full all the time , our controllers don't have any of the cal rubbish to mess about with , so apart from the lower flow rate there been no problems at all

ive used 6ml befoure for ages with no problems

 
Question am I right in thinking (which I don't do very often) if you started from pump to brush with 5mm you would get less flow rate and pressure? even though the tube in the pole is only 5mm? I know that house pluming can be 22mm 15mm and micro bore starts of big and reduces. In the end the water will hit 5mm restriction?

just a question for a Monday afternoon guys

 
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Question am I right in thinking (which I don't do very often) if you started from pump to brush with 5mm you would get less flow rate and pressure? even though the tube in the pole is only 5mm? I know that house pluming can be 22mm 15mm and micro bore starts of big and reduces. In the end the water will hit 5mm restriction?just a question for a Monday afternoon guys
its all down to the now quick the water can be pushed or draw throw the pipe doesn't matter how big the pump is as there a max speed water will travel down diffent size pipes there a good bit of sicnce to it

that's why fire engines use use half a foot pipes and not micro bore

 
It is less effort to pump through 100m of microbore and then skinny pole hose than it is to pump through just pole hose all the way

 
Can see your point Daveyboy but is there much difference in pressure /flow between 6mm and 8mm to the pole hose from the pump?

I'm just starting with wfp and this seems to be one of my first problems which is best to go for 6mm or 8mm on the reel to the pole?

 
Can see your point Daveyboy but is there much difference in pressure /flow between 6mm and 8mm to the pole hose from the pump?

I'm just starting with wfp and this seems to be one of my first problems which is best to go for 100m 0f 6mm or 8mm on the reel to the 5mm pole hose?

 
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Can see your point Daveyboy but is there much difference in pressure /flow between 6mm and 8mm to the pole hose from the pump?I'm just starting with wfp and this seems to be one of my first problems which is best to go for 100m 0f 6mm or 8mm on the reel to the 5mm pole hose?
Yes there is as 6mm is roughly half the size of 8mm hose, so the the flow will be restricted. The pressure is the same as that's what the pump delivers.

Another poster on the other forum couldn't understand why a difference in 2mm hose size (8mm minibore to 6mm microbore) should make a difference in flow. Doug Atkinson from Daqua posted this in reply

It does -------, makes at least 30% reduction in flow

Take a look at this;

Water - flow through pipes

I realise its steel pipe but I see the flow rate difference between 6mm and 8mm bore steel pipe is considerable. At 4 bar the flow through 6mm pipe is 0.022 liters per second. The 8mm pipe its 0.056 liters per sec at the same pressure. So a 6mm tube will only allow fractionally less than 1/2 the volume of water at 4 bar. Our hose coiled up around a hose reel will probably reduce those figures a bit more.

Hot water will have a higher (or is it lower) viscosity (less dense) so will flow better through a smaller diamt hose. So most hot water users happily use microbore hose.

http://www.frca.co.uk/Documents/100308%20Physics%20of%20flowLR.pdf

Interesting read these 7 pages.

Look at the difference between Laminar flow and Turbulent flow. Once fluid in a tube reaches a certain speed it become turbulent. Once it becomes turbulent it requires 4 times the amount of pressure to double the flow rate. Fluid through hose coiled on hose reels won't be laminar in flow but turbulent.

To calculate the area of a circle the formula is

A = π r2

A 6mm id hose is fractionally more than half the size of an 8mm hose.

A 3mm jet is a little more than twice the size of a 2mm jet.

A 1mm jet is about 1/4 of the size of a 2mm jet.

 
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Well I must have super pump . Changed from minibore to microbore about 5 years back . The flow didn't change . Changed from microbore to pole hose a few months back. Still no change on the flow . The vzristream has been on number 4 all the time . Same pump as well .

 
At flow rate of 4 on a Varistream we get about 2 LPM of water at the brush. Microbore hose should handle that without to much issue. So you probably won't notice a drop in flow rate between microbore and minibore at those settings.

But the water will be flowing faster through the hose than it would with minibore. A faster flow rate will make turbulence inside the hose a greater possibility.

Well I must have super pump . Changed from minibore to microbore about 5 years back . The flow didn't change . Changed from microbore to pole hose a few months back. Still no change on the flow . The vzristream has been on number 4 all the time . Same pump as well .
 
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Well I must have super pump . Changed from minibore to microbore about 5 years back . The flow didn't change . Changed from microbore to pole hose a few months back. Still no change on the flow . The vzristream has been on number 4 all the time . Same pump as well .
As long as its all set up correctly (calibration etc) you shouldn't have any problems. I use microbore and am on the same shurflo pump after 9 years :thumbsup:

 
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