New hose problems. Any help?

[Chris Dall]

Bought grippas 6mm I/d hydro hose 100m.

Pumps always run at 100psi (I love my water) but I'm getting gash flow through this hose. Gone from WCW 8mm I/d. Pumps fine as it's going well with my other 8mm I/d hose. Can't work out why I'm getting such a poor flow??? It's going about 50%

 

[Adam curtis]

Have u got a digital flow controller if so try adjusting that or do a auto cal

Sent from my iPhone using Window Cleaning Forums mobile app

 

[Chris Dall]

No controllers I'm afraid, 100% all the time

 

[Green Pro Clean Ltd]

So you have no flow controller just a pump running flat out? Your wondering why you're getting less water flow through 6mm hose pipe than you were through your 8mm hose? Is that it?

 

[Chris Dall]

Thought I'd add both pumps are fine with my 8mm hose so not a pump issue I doubt

 

[Chris Dall]

Yes

So you have no flow controller just a pump running flat out? Your wondering why you're getting less water flow through 6mm hose pipe than you were through your 8mm hose? Is that it?

 

[Chris Dall]

2mm surely can't make a difference?

 

[tlwcs]

2mm surely can't make a difference?

over how long!

 

[Chris Dall]

I understand it's going to restrict the flow, but when I went from 12mm I/d to 8mm I/d had no change what so ever. I drop another 2mm and this.

 

[doug atkinson]

2mm surely can't make a difference?

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

 

[spruce]

Have a look at this @Chris Dall

Water - flow through pipes

I realise its steel pipe but I see the flow rate difference between 6 or 8mm bore steel pipe is considerable. 6mm 0.022 as opposed to 0.056 liters per sec 8mm. 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.

 

[Chris Dall]

That makes a lot of sense thanks, dont know how some people can work with such little water on the windows!! Personal preference i understand.

Just didn't realise 2mm would have such a large impact.

For sale : 6mm Grippas Hyrdo heat hose lol

 

[tlwcs]

That makes a lot of sense thanks, dont know how some people can work with such little water on the windows!! Personal preference i understand.
Just didn't realise 2mm would have such a large impact.

For sale : 6mm Grippas Hyrdo heat hose lol

I'll buy 50 metres if you really are selling

Tony

 

[Chris Dall]

It's a 100m hose! Don't really fancy cutting it up. £78 I paid, used for one house. Yours for £40

 

[tlwcs]

It's a 100m hose! Don't really fancy cutting it up. £78 I paid, used for one house. Yours for £40

Where abouts are you Chris? And is it on a reel or of the spaghetti type

 

[Chris Dall]

Portsmouth mate. I can spool it up for you and post tho

 

[tlwcs]

Portsmouth mate. I can spool it up for you and post tho

Cool, price it up and if reasonable, I'll take it

Tony

 

[spruce]

That makes a lot of sense thanks, dont know how some people can work with such little water on the windows!! Personal preference i understand.
Just didn't realise 2mm would have such a large impact.

For sale : 6mm Grippas Hyrdo heat hose lol

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.

I know we have touched on the difference between microbore and minibore on a previous thread last year;

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

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