Greetings to the Forum. As a young engineer and recent college graduate I hope you all will help me fill in the gaps that college left. And there are many.

One of the many projects in which I am employed is a Clean-in-Place system for conveyor belts. Due to this particular system's requirements there is very little clearance between the spray bar and the conveyor belt, not enough room for conventional nozzles. Is it possible to cut a pipe such that the holes/slots will spray in a nice flat fan pattern? Thus far we have been unsuccessful.

Insights welcome,

Michael

 

Hi Michael,

I would use the spray jets that farmers use on their sprayers - you can get different fan angles - and the ones I have used before are about 10mm diameter roughly. Below is an example. The picture shows you what they typically look like. The second picture shows you the "performance".
If you pop into the local farm shop - I am sure they will have a selection.

http://www.alibaba.com/product-detail/Brass-fan-jet-spray-nozzles-brass_1991771259.html

http://www.steinen.com/industrial/usa/english/fan-jet-nozzles.php


Hope this helps.

 

Lochnagar,

Thank you for your response however I don't believe these will work. The problem is that the distance between the spray bar and the belt is only approximately 1". Nozzles might not even fit, let alone have enough room for the spray pattern. Is there a way to drill/groove/machine a pipe or tube along its longitudinal axis so as to achieve a flat fan spray?

So far we have tried slotting a 5/8" tube with a 0.025" and a 0.012" jewelers saw, neither produced a fan. Which, in hindsight makes sense.

 

This might be an opportunity to make a 3d printed part with integrated spray nozzles.

Or.

I would make a 2 piece "tube" that bolts together. Machine a pocket in one part for fluid flow. bolt on a flat plate to seal.
Along the edge of the part machine shallow recesses for the water to spray out.
You will have to experiment with the length,depth, width and angle of the sides to get the spray pattern you want.
A smear of RTV on the surfaces before bolting together will seal it.

 

Hi Michael,

I have personally used this type of nozzle for cleaning a pipe - and the distance between the pipe and the nozzle was of the order of 25mm. All you have to do is drill and tap your pipe to accept the nozzle. From memory the nozzles are very in-expensive.

If you think laterally, if the distance of 25mm is perceived as a "problem" - and without a picture it is hard to see if this is, or is not a problem, then rotate the pipe with the nozzles fitted inside - so that instead of the water striking the belt at 90 degrees - it strikes it at say 45 degrees - so you will now have 1.41 x 25mm = 35mm between the nozzle and the belt.

It is always a good idea to post a picture of the problem - so that everyone can see the "issues" - but hopefully the above is of some help.

 

All right, I'll draw something up quickly here.

Lochnagar, are you saying that for the end of the nozzle to the cleaning surface was 25mm or the end of the pipe that will receive the nozzle to the cleaning surface is 25mm?

 

Hi Michael,

The total length of the nozzle I used was 23mm - but this obviously includes the thread, and the hex section, and the spray section. It had a NPT thread, and so when it was fully screwed into the manifold - which would be the pipe in your case - the nozzle protruded out by 12mm. From the front of the spray section to the pipe was 25mm. However, if you look at the data sheet I gave you a link to above - you can get shorter nozzles than the ones I used in my application.

Just reading your text above - I am getting the impression you are talking about fitting a nozzle in the end of the pipe - i.e. the nozzle and the pipe share the same axis.
However, in my application, I drilled and tapped the delivery pipe - so that it was like a manifold - thus the axis of the nozzle was at 90 degrees to the axis of the delivery pipe. I would have thought this method would be of more use to you - if you are cleaning a wide belt.

As I said above - there could be merit in rotating the delivery pipe (using my method of the manifold above) - to 45 degrees - since not only will this give you more room - but it will "cut the debris" you have off the belt.

Hope this helps.

 

Let me know if you can see these two pictures.

https://www.dropbox.com/s/53r91i48deew9bo/CIP Demo.JPG?dl=0
https://www.dropbox.com/s/gr8r40jmsj88zcb/CIP Demo2.JPG?dl=0

The first picture is a side view and the second shows the underside at an angle. There is more to this system but I cut it out for simplicity. The belt is about 5' long and travels perpendicular to the longitudinal axis of the pipes. The operating temperature of the system is somewhere below 200F, it is sitting in an oven around 300F but the water should be keeping it pretty cool.

Lochnagar, it is funny that you thought that. Your previous messages led me to believe that you were the one fitting the nozzles on the end. Our original idea was to go with a manifold tilted about 60 degrees from vertical. That would allow about 2" of space.
I hope that clears things up. I'll follow through with everyone's suggestions, though I welcome anymore that you have.

Thanks

 

All the spray bars I have come across - have been a tube (i.e. a manifold) with nozzles screwed in perpendicular to the axis of the tube - which is what I originally suggested - like in the pictures in the link below.

With your idea of a full length slot - you will not be able to build up the pressure you need - to get a "nice fan shape" - and to get effective cleaning.

http://www.mcgearyengineering.com/

Hope this helps.

 

I guess I wasn't very clear in what I was planning to do. Lochnagar, what you describe is precisely what I am trying to do. That slot was just a visual aid. Regardless, I think we will go with a deflected nozzle. There is a little room below the pipe and this will increase the distance from spray to belt.

Thanks for your input. Even though I wasn't able to get everything across clearly you still helped me find what I needed.