Interested In Advertising? | Contact Us Here
Warning!

 

Welcome to Clean It Up; the UK`s largest cleaning forum with over 34,000 members

 

Please login or register to post and reply to topics.      

 

Forgot your password? Click here

davidpitts

Minibore hose for pressure washer
« on: March 12, 2009, 10:00:56 pm »
Just wondered if it would be ok to use 100m of minibore(8mm) to feed my pressure washer, I think it uses 15l per minute.

karygate

  • Posts: 694
Re: Minibore hose for pressure washer
« Reply #1 on: March 13, 2009, 07:32:36 am »
at first i would have said no chance but saying that a normal hose going into a butt and filling off that works and 8mm is not much smaller so you will have to give it a go but you must feed from a water butt or similar to keep the water flow right.
gary

davidpitts

Re: Minibore hose for pressure washer
« Reply #2 on: March 13, 2009, 08:44:16 am »
I have been having a bit of a think about this, if mains pressure is good and say for instance it delivered 30l per min at tap it would still be coming out of 100m of minibore at 30l per minute only coming out faster if you know what i mean, like when you squeeze the end of an hose pipe to make water jet more powerful, hope this makes sense.  Cheers Dave :-\

BDCS

  • Posts: 4777
Re: Minibore hose for pressure washer
« Reply #3 on: March 13, 2009, 09:05:35 am »
No hope - The pressure loss over that length in microbore will be too much, the mains pressure would have to be huge

davidpitts

Re: Minibore hose for pressure washer
« Reply #4 on: March 13, 2009, 10:20:38 am »
What hose should I use if I am connecting to an outside tap and what length, for the jobs I have done up to now I have used 30m of half inch, Cheers Dave.

BDCS

  • Posts: 4777
Re: Minibore hose for pressure washer
« Reply #5 on: March 13, 2009, 01:06:38 pm »
I'd use 1/2" but you could proove your microbore by connecting it up at home and measuring the output over a minute

drivewasher

  • Posts: 380
Re: Minibore hose for pressure washer
« Reply #6 on: March 13, 2009, 01:07:27 pm »
The only way really to ensure your machine gets 15 Litres a min is to draw from a tank/butt via a 20mm suction hose as short as possible but no longer than 4 metres

If any tap only gives 14.5 litres a min at the end of a hose then you will be slowly damaging your machine if connected directly to machine. You will find on  a lot of jobs the water level in the butt will slowy fall indicating water delivery of less than you need
I'm always in the poo, it's just the depth that varies

drivewasher

  • Posts: 380
Re: Minibore hose for pressure washer
« Reply #7 on: March 13, 2009, 01:19:38 pm »
What hose should I use if I am connecting to an outside tap and what length, for the jobs I have done up to now I have used 30m of half inch, Cheers Dave.

It all depends on the site really. I did 160 metres of flags yesterday. A 1960's bungalow on a big estate. I could P quicker than the tap. My 280 litre tank (whilst it's still flling) emptied and stopped me in about 20 mins. I started brushing up etc and brewing up while tank refilled for about 20/25 mins (tank not full to the stop) then started again.
I recon job took 1.5 hours at least longer than if tap delivered 15+ litres a min.
Also just say tap did give you 15+ litres a min then if custy puts washer on or runs inside sink tap then your flow will slow. Also on an estate for example about 3.30 pm or around lunch time all other properties are active with drawing water so yor flow drops even more.
Morrell of this story is use a tank or a butt!
I'm always in the poo, it's just the depth that varies

BDCS

  • Posts: 4777
Re: Minibore hose for pressure washer
« Reply #8 on: March 13, 2009, 06:00:46 pm »
I assumed that everybody uses a water butt of some description

davidpitts

Re: Minibore hose for pressure washer
« Reply #9 on: March 14, 2009, 06:49:27 pm »
Another thought I had on this (I'm probably talking a load of rubbish) could it be possible for the p/washer to suck the amount of water it requires from the mains , much the same way a booster pump does to force water through the filters for purifying water.

BDCS

  • Posts: 4777
Re: Minibore hose for pressure washer
« Reply #10 on: March 14, 2009, 06:54:33 pm »
That would cause your pump to cavitate

davidpitts

Re: Minibore hose for pressure washer
« Reply #11 on: March 14, 2009, 07:06:27 pm »
Sorry , what does cavitate mean.

karygate

  • Posts: 694
Re: Minibore hose for pressure washer
« Reply #12 on: March 15, 2009, 05:56:11 am »
like myself and drivewasher says you have to feed your water into a tank or butt to make sure you have a constant flow all the while. i do not know what cavitate means either but it is probably the same as buggering your pump up in no time. ;D
gary

Rob_Mac

Re: Minibore hose for pressure washer
« Reply #13 on: March 15, 2009, 06:33:54 am »
Cavitation is defined as the phenomenon of formation of vapour bubbles of a flowing liquid in a region where the pressure of the liquid falls below its vapour pressure. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation, and noninertial cavitation. Inertial cavitation is the process where a void or bubble in a liquid rapidly collapses, producing a shock wave. Such cavitation often occurs in pumps, propellers, impellers, and in the vascular tissues of plants. Noninertial cavitation is the process in which a bubble in a fluid is forced to oscillate in size or shape due to some form of energy input, such as an acoustic field. Such cavitation is often employed in ultrasonic cleaning baths and can also be observed in pumps, propellers, etc.

Since the shock waves formed by cavitation are strong enough to significantly damage moving parts, cavitation is usually an undesirable phenomenon. It is specifically avoided in the design of machines such as turbines or propellers, and eliminating cavitation is a major field in the study of fluid dynamics.

That should clear it up. It is my opinion that you should always be using a tank, as a reservoir, on any job, then you safeguard against the above happening on the house pipework as well.

Rob ;D

davidpitts

Re: Minibore hose for pressure washer
« Reply #14 on: March 15, 2009, 10:23:20 am »
Thanks for your replies , I will get myself a water butt , Cheers Dave.  :)

drivewasher

  • Posts: 380
Re: Minibore hose for pressure washer
« Reply #15 on: March 15, 2009, 11:52:49 am »
like myself and drivewasher says you have to feed your water into a tank or butt to make sure you have a constant flow all the while. i do not know what cavitate means either but it is probably the same as buggering your pump up in no time. ;D



He, hee,  ;D
I'm always in the poo, it's just the depth that varies

BDCS

  • Posts: 4777
Re: Minibore hose for pressure washer
« Reply #16 on: March 15, 2009, 11:53:07 am »
I use a wheelie bin

drivewasher

  • Posts: 380
Re: Minibore hose for pressure washer
« Reply #17 on: March 15, 2009, 11:57:22 am »
I assumed that everybody uses a water butt of some description

Apparently not!

Thanks for your replies , I will get myself a water butt , Cheers Dave.  :)
I'm always in the poo, it's just the depth that varies

davidpitts

Re: Minibore hose for pressure washer
« Reply #18 on: March 15, 2009, 02:19:56 pm »
When I got the pressure washer last year I went on a one day course at a place called direct cleaning services ,so I would get a good idea of all the basics , it was quite informative but alot of it was H&S but there was no mention of butts and bins , so much for training then , I think I was robbed £250 , oh well you live and learn ,  no more courses for me I'll just ask you guys , thanks again Dave. :-[

BDCS

  • Posts: 4777
Re: Minibore hose for pressure washer
« Reply #19 on: March 15, 2009, 08:42:33 pm »
If your pump has to pull the water from the hose then you are going to wear the pump quickly, it sounds like you have a pump with an internal unloader ie no return hose. to give the pump a positive feed you fill a tank with water and the feed hose is a bigger bore taken from the bottom of the tank and with an external return it goes back to the tank whilst unloading so it dos'nt get hot which also damages pumps