Nozzle Trivia

[Scott Stone]

No idea on the speed (velocity) the water is leaving the nozzle.

Second questions answer, I think spinning the nozzle into or away from the surface to be cleaned does not significantly affect the velocity the water hits the cement for typical surface cleaner nozzle heights.

The velocity is so high at 1 to 1.25 inches from the nozzle that it maybe insignificant.

However as the height increases beyond 1 to 1.25 inches the spinning speed affects the velocity the water hits the surface exponentially.

I think your assessment is wrong. Here is the reason why. I am going to use a metaphor to explain it. If someone hits your arm with a glancing blow, the impact is not too great. If it is a direct blow, it hurts a bit more. If someone is on a bicycle hits you, assuming the same force, impact will be the greatest. Since A nozzle directed into the rotation will by necessity be powered, the net impact will be reatst. It will also be. Larger because. It does not. NeeD water forCe to propel the spray. Bar.

 

[810f250]

I think your assessment is wrong. Here is the reason why. I am going to use a metaphor to explain it. If someone hits your arm with a glancing blow, the impact is not too great. If it is a direct blow, it hurts a bit more. If someone is on a bicycle hits you, assuming the same force, impact will be the greatest. Since A nozzle directed into the rotation will by necessity be powered, the net impact will be reatst. It will also be. Larger because. It does not. NeeD water forCe to propel the spray. Bar.

What you are saying is true Scott, about impact with respect to direct and lancing blow.

Impact: The force or impetus transmitted by a collision.

Assuming the same gpm, psi, nozzle size, temp, etc (parameters) , just switching surface cleaners from motorized (turbo twister, which turns the water into the dirt, similar to when you are removing gum with a wand{this is the standard setup} ) to non-motorized surface cleaner (which turns the water away from the surface)

A direct (straight down) impact has only one component of force (y plane)

A lancing blow (angled in a non-motorized or sometimes in a motorized surface cleaner {standard setup} ) has a smaller component of force in the y plane because it now has two components of force both in the y and x planes

The components of force produced in the nozzle fluid stream by the pressure washer is almost the same for motorized or non-motorized surface cleaners, provided that the nozzle arm orientation angles are the same and all the other parameters.

However it is more efficient use of a pressure washers cleaning units to drive the stream into the dirt(Turbo Twister), than away from the dirt.


The question Tom asked was about the effect on velocity of the fluid if it is rotated into the surface like a motorized surface cleaner compared to a non-motorized.

I believe that the Velocity if the fluid is not affected significantly, thus the Impact is the about the same.

Motorized units can be setup two ways.
Setup 1) angled nozzle stream rotated into the surface (See Figure)
Setup 2) a straight down rotated nozzle stream. (I think Jim's is set like this)

In Setup 1) the Impact depends on the angle of the forward lancing blow and to some small extent the rpms of the motorized unit same parameters. The manufacture probably has the two variables optimally set. (Turbo Twister is 15 deg forward orientation at 1500 rpm).
The advantages of this turbo twister setup is getting the fluid stream to perform a lifting action and secondly any particular spot experiences this lifting action from two different directions. (right then left depending on the direction of rotation or forward/backward motion of the motorized surface cleaner)

In setup 2) you cannot achieve a higher impact than straight down for the same parameters

I hope this is helpful to all.

 

[810f250]

Any more responses to this pole?

 

[Tony Shelton]

Any more responses to this pole?

I had my doubts about you Nigel with all the science and calculations.......but now I know you really are a pressure washer......it's Poll. P-O-L-L. :woot::thumbup:

 

[810f250]

I had my doubts about you Nigel with all the science and calculations.......but now I know you really are a pressure washer......it's Poll. P-O-L-L. :woot::thumbup:

So much for my English. lol

What effect does switching from 2 arm to 3 arm have on impact from each nozzle? ....; if both the sets of nozzles in the 2 arm and 3 arm bars are the same angle.

Example: For a pressure washer pump like General's TSF2021 8 gpm at 3600 psi.

Running a Surface cleaner with 2 nozzles at 15 degrees in the 2 arm

or Running a surface cleaner with 3 nozzles at 15 degrees in the 3 arm

Which has a potential better cleaning capacity? (Greater Impact)

 

[810f250]

Why do you think, most are impressed when they move from 4 gallon per minute (gpm) 3500 psi machines to industry standard 5.6 gallon per minute 3500psi machines?


Impact increases by?

 

[810f250]

Stainless Steels Nozzles Anyone?

About how much more resistant to wear is a hardened stainless steel nozzle to a regular stainless steel nozzle.

Whats on your lance?

 

[Christopher]

The more nozzles you have, it divides your flow (gpm's) by each nozzle where the pressure stays the same.

When you have a 2-nozzle spray bar and 5.5 gpm machine, you have 2.75 gpm's hitting the ground through each nozzle.

When you have a 3-nozzle spray bar and 5.5 gpm machine, you have 1.83
gpm's hitting the ground through each nozzle.

You have more force hitting the ground with less nozzles where when you have more nozzles, you are dividing the flow with each nozzle you add.

 

[810f250]

The more nozzles you have, it divides your flow (gpm's) by each nozzle where the pressure stays the same.

When you have a 2-nozzle spray bar and 5.5 gpm machine, you have 2.75 gpm's hitting the ground through each nozzle.

When you have a 3-nozzle spray bar and 5.5 gpm machine, you have 1.83
gpm's hitting the ground through each nozzle.

You have more force hitting the ground with less nozzles where when you have more nozzles, you are dividing the flow with each nozzle you add.

Thanks for you response Chris, for a moment there I taught this thread was ....

I agree with what you say Chris, about the force.

However, you do not always have full pump flow when you divide the gpm's of a machine by the number of arms in a surface cleaner and then use the answer as the size of tip needed.

Example I have a 6 gpm machine at 3500psi, I have a 2 arm surface cleaner, the tip that the division of 6 by 2 yields is 3.0

If I use a 3.0 tip, about how much flow can I get to my surface cleaner 200ft away with 3/8 hose?

The intent of this thread is to show how critical that little thing called the "nozzle" is. The best engine and pump is nothing with out a nozzle, because without nozzle it is not a pressure washer, its just an engine driven water pump.

 

[Christopher]

I got you now.

I was thinking that people would be using the correct nozzles for their machine knowing that they have to divide the flow for the amount of nozzles they are using so they get the correct gpm's out of their machine.

But.....

There are a lot of people out there that do not know what the numbers on the nozzles mean and some do not know how to use the nozzle chart. That should have been taught to them when they bought their machine. Many, many vendors out there do not explain that to their customers when they sell equipment, I was not told either and had to learn from someone else than who sold me my trailer rig.

People need to know what those numbers are so they make sure that they use the correct nozzles for their machines not only for the right gpm's but also the correct psi.

A lot of guys I have talked to (even recently) do not know what the numbers on the nozzles mean.

The first two numbers on the nozzle are the spray pattern like 00 means that it is a "0" degree nozzle or straight stream where the 15 means it is a 15 degree fan pattern, the 25 means it is a 25 degree fan pattern, etc....

The second group of numbers is the orifice size which will be the size for your machine's gpm's and psi. You look at the nozzle charg for your psi and gpm and it will show you an orifice size and that is the one you use for your machine. You go and get the right orifice size along with the fan pattern nozzles you like to use.

For multiple nozzles like spray bars for surface cleaners you will divide the orifice size by the number of nozzles in the spray bar.

Example: My machine is a 5.6gpm 3000 psi hot water rig so on the nozzle chart it shows that the orifice size is 6.5 so on a spray bar that uses 2 nozzles you would divide that 6.5 by 2 so you end up with 3.25 orifice size.

I have not found a place that sells the 3.25 orifice nozzles so I use the 3.0 nozzles (2 since my spray bar uses 2 nozzles).

If I had a 3-nozzle spray bar (I do on the Whirl A Way Stainless Steel 24" surface cleaner) then I would divide that 6.5 orifice by 3 (3 nozzles) and get the 2.166 size orifice but again, most places sell the whole and half number orifice sizes so I would just go with 3 of the number 2 orifice nozzles. Then I would just pick the spray fan pattern I like to use.

Sometimes I like to use the 25 degree fan pattern on the surface cleaner but once in a while the place is very dirty so I use the 15 degree fan nozzles, it is personal preference.

The nozzles not only divide the flow but will restrict the psi going through them but when you use the correct orifice nozzles for your machine you usually get the correct flow in psi and gpm's you need but you can restrict them if you don't have the correct orifice sizes either intentionally or unintentionally depending on if you do this on purpose or accidentally.

Sometimes you want to use lower psi on jobs so you use larger orifice nozzles or adjust the unloader or if it is wand work, you can use the dual-lance wand, just personal preference.

Hope this helps.

 

[810f250]

Thanks for the reply Chris, good info



Other things that most over look is the actual pump rpm.

Pumps are rated at a maximum rpm, at that particular rpm the plungers swept volume delivers a maximum gpm output, then the manufacturer calculates the maximum recommended sustainable pressure.

So if you are not certain of your exact pump rpm, you really dont know what it is outputting (gpm). The loaded engine rpm , pulley sizing or gear box ratio affect the pump rpm input. Most may have a rpm gage on the engine but we have to trust or check that the manufacturer sized the pulley right. (choosing the "correct" pulley size brings you close to the desired pump input, it still has to be fine tuned with the safe operating range of the engine).

Most times a nozzle is sized based on the pump head pressure and flow, if you have a large pressure loss between the head and the end of the length of hose, your gpm maybe significantly affected.

 

[Christopher]

Very true Nigel!

I believe that the pressure loss with my machine (5.6gpm 3000psi) will be about 138psi loss per hundred feet using 3/8" I.D. Hose.

I think that my 8gpm 3000 psi machine loss is about 300psi per 100' using 3/8" I.D. Hose.

It is good to know these numbers for many reasons.

 

[Ron Musgraves]

Truly Great Thread

 

[Grime Busters LLC]

Very true Nigel!

I believe that the pressure loss with my machine (5.6gpm 3000psi) will be about 138psi loss per hundred feet using 3/8" I.D. Hose.

I think that my 8gpm 3000 psi machine loss is about 300psi per 100' using 3/8" I.D. Hose.

It is good to know these numbers for many reasons.

I have recently learned a valuable lesson with my new trailer set-up and my experience with PSI and GPM loss. And this thread along to the members who I have been in contact with have enlightened me and provided very valuable information, and as I have expressed I am very grateful.

My 2 new 9 GPM, 3500 PSI skids were suffering a 1000 psi loss at the end of 300" of 3/8" hose. Not acceptable !!!! Did some research and learned that friction loss caused by the restriction is critical to determine.

I have talked with several "experts" in the field of hose suppliers. The numbers they supplied varied + or - 10%, but this is what I have learned.

At 9 GPM, 3500 PSI, using 3/8" hose, you lose an average of 4 PSI per foot of hose, compared to 1.3 PSI using 1/2" hose. HUGE difference. Everyone agrees that there is a "curve" at a certain length of hose where you'll experience a more substantial drop in PSI, but no one agrees at which point that occurs. I was told by one "expert" that if I reduced the 300' of 3/8" hose down to 250', I would experience at least a 500 PSI increase. I tried this theory, experienced about 100 PSI increase.

All Mi T M machines at 8 GPM and above ship with 1/2" hose. Hydro Tek shipped my 2 skids with 3/8" hose. But when you go to Hydri Tek's distributor section of their website, and want to custom design a skid, they will not let you order anything less than 1/2" hose on a machine that puts out 8 GPM or better.

Since this is my first skid(s) over 5.5 GPM, I did not realize the effect of PSI loss due to friction x GPM. And apparently neither did any of the local distributors I received quotes from for this dual skid specs I required. All quoted with 3/8" hose.

Needless to say, I have ordered 500' of 1/2" 2 wire hose. 250' per reel. The cost of this misjudgment will be shared between Hydro Tek, my supplier and I.

Live and learn. PSI output at the pump means nothing, psi at the business end of your hose is the true indicator.

How does one accurately measure GPM at the business end of your hose ?

And how does one measure PSI loss caused by the spinner ?

 

[Jim@Garagecleaning]

What you are saying is true Scott, about impact with respect to direct and lancing blow.

Impact: The force or impetus transmitted by a collision.

Assuming the same gpm, psi, nozzle size, temp, etc (parameters) , just switching surface cleaners from motorized (turbo twister, which turns the water into the dirt, similar to when you are removing gum with a wand{this is the standard setup} ) to non-motorized surface cleaner (which turns the water away from the surface)

A direct (straight down) impact has only one component of force (y plane)

A lancing blow (angled in a non-motorized or sometimes in a motorized surface cleaner {standard setup} ) has a smaller component of force in the y plane because it now has two components of force both in the y and x planes

The components of force produced in the nozzle fluid stream by the pressure washer is almost the same for motorized or non-motorized surface cleaners, provided that the nozzle arm orientation angles are the same and all the other parameters.

However it is more efficient use of a pressure washers cleaning units to drive the stream into the dirt(Turbo Twister), than away from the dirt.


The question Tom asked was about the effect on velocity of the fluid if it is rotated into the surface like a motorized surface cleaner compared to a non-motorized.

I believe that the Velocity if the fluid is not affected significantly, thus the Impact is the about the same.

Motorized units can be setup two ways.
Setup 1) angled nozzle stream rotated into the surface (See Figure)
Setup 2) a straight down rotated nozzle stream. (I think Jim's is set like this)

In Setup 1) the Impact depends on the angle of the forward lancing blow and to some small extent the rpms of the motorized unit same parameters. The manufacture probably has the two variables optimally set. (Turbo Twister is 15 deg forward orientation at 1500 rpm).
The advantages of this turbo twister setup is getting the fluid stream to perform a lifting action and secondly any particular spot experiences this lifting action from two different directions. (right then left depending on the direction of rotation or forward/backward motion of the motorized surface cleaner)

In setup 2) you cannot achieve a higher impact than straight down for the same parameters

I hope this is helpful to all.

.
.
.
.



Our turbo twisters have been upgraded with a 13 HP with the sole purpose to turn the wands and nothing else. 6 HP cannot achieve the RPMS we are looking for.

Currently we are at 4,000 RPM's. Our units are usually twice as aggressive as the standard surface cleaner and is NOT recommended for cleaning " Soft" cement. We will remove the creme of the cement with one quick pass !

 

[Christopher]

Until I get my new trailer later this year or next year I will just keep on with the loss of psi with the 3/8" hose but with the new trailer I will be running 1/2" hose for the 8gpm machine so less loss of psi.

A lot of guys hate using the 1/2" hose because it is a little heavier and stiffer than the 3/8" hose but when doing a lot of flatwork, the overall benefits are worth the hassle.

If you are using very hot water, I would make sure that your hose is rated for the temps you will be running.

I agree, this is a very good thread.

 

[Christopher]

Something else to consider is your hose reels. If you are not using the Super Swivel, look inside the opening where the water comes out into the hose on the reel and see how small that opening is.

The immitation Rapid Reel hose reel (aka general hose reel) has a very tiny hole that will restrict your flow.

When I changed out hose reels earlier this year I put on a Hannay Reel that looks like it has a Super Swivel on there and I looked at the passage in the swivel and it is large, like about 1/2" since the hose reel is 1/2" so no restrictions there.

That was on my water supply hose reel to the tank. Now the tank seems to fill about twice as fast as before! The opening in the swivel is the big difference since I am using the same supply hose but added another 125' to the 100' that was on the old reel so the water tank fills about twice as fast with more hose because of that larger opening in the swivel.

Switch out the swivels to the Super Swivel brand and look inside them, the opening is a lot larger so if you change out to 1/2" hose, get the Super Swivel so that cheap brass swivel does not slow you down.

 

[810f250]

Truly Great Thread

I think so too Ron

 

[810f250]

I have recently learned a valuable lesson with my new trailer set-up and my experience with PSI and GPM loss. And this thread along to the members who I have been in contact with have enlightened me and provided very valuable information, and as I have expressed I am very grateful.

My 2 new 9 GPM, 3500 PSI skids were suffering a 1000 psi loss at the end of 300" of 3/8" hose. Not acceptable !!!! Did some research and learned that friction loss caused by the restriction is critical to determine.

I have talked with several "experts" in the field of hose suppliers. The numbers they supplied varied + or - 10%, but this is what I have learned.

At 9 GPM, 3500 PSI, using 3/8" hose, you lose an average of 4 PSI per foot of hose, compared to 1.3 PSI using 1/2" hose. HUGE difference. Everyone agrees that there is a "curve" at a certain length of hose where you'll experience a more substantial drop in PSI, but no one agrees at which point that occurs. I was told by one "expert" that if I reduced the 300' of 3/8" hose down to 250', I would experience at least a 500 PSI increase. I tried this theory, experienced about 100 PSI increase.

All Mi T M machines at 8 GPM and above ship with 1/2" hose. Hydro Tek shipped my 2 skids with 3/8" hose. But when you go to Hydri Tek's distributor section of their website, and want to custom design a skid, they will not let you order anything less than 1/2" hose on a machine that puts out 8 GPM or better.

Since this is my first skid(s) over 5.5 GPM, I did not realize the effect of PSI loss due to friction x GPM. And apparently neither did any of the local distributors I received quotes from for this dual skid specs I required. All quoted with 3/8" hose.

Needless to say, I have ordered 500' of 1/2" 2 wire hose. 250' per reel. The cost of this misjudgment will be shared between Hydro Tek, my supplier and I.

Live and learn. PSI output at the pump means nothing, psi at the business end of your hose is the true indicator.

How does one accurately measure GPM at the business end of your hose ?

And how does one measure PSI loss caused by the spinner ?

The loss is exponential Jim you would have to deterime at what point the gradient of graph of pressure loss vs hose length at a prticular size is greatest.

Real world testing is great, 1000psi is substantial. Glad to hear that you only have to fit 1/3 the bill.

 

[810f250]

.
.
.
.



Our turbo twisters have been upgraded with a 13 HP with the sole purpose to turn the wands and nothing else. 6 HP cannot achieve the RPMS we are looking for.

Currently we are at 4,000 RPM's. Our units are usually twice as aggressive as the standard surface cleaner and is NOT recommended for cleaning " Soft" cement. We will remove the creme of the cement with one quick pass !

I spoke with the owner of Turbo Twister company on Friday last, we spoke for quite a while,

I will call yours the "Twin Turbo Twister", Jim