Recent content by beds87

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    Back pressure on a pipe by squeezing it shut

    The pipework does need to be changed every few days but the cost and time of swapping a pipe out against a PLC controlled festo solenoid valve. The pipework can also be changed when each product is swapped out and then cleaned out when the nozzle is changed.
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    Back pressure on a pipe by squeezing it shut

    Those 200 bottles per min is shared between 4 nozzles so each nozzle operates 50 times a min
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    Back pressure on a pipe by squeezing it shut

    The issue is we are dosing 200 bottles of product per min of varying specific gravity and weights. We have tried a wide array of mechanical valves yet nothing can keep up or doesn't drastically wear over a short period. When the nozzle size is correct to the product there are no leaks. It's...
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    Back pressure on a pipe by squeezing it shut

    I understand what you are saying now. So I could: Before each batch is pumped out I could use a tube the same length and diameter as the dosing unit tube, place a nozzle on, dip it into the product and block the top end and drop nozzle sizes until it doesn't drip.
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    Back pressure on a pipe by squeezing it shut

    You have now lost me. All that is currently tested on each batch of product is the weight and specific gravity. Is there a way to calculate surface tension using the specific gravity? Any further tests I would need to implement. I know the weight so could calculate density. I was then...
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    Back pressure on a pipe by squeezing it shut

    To calculate this for each batch someone would need to place a tube into a known level of liquid and determine how higher past the original level the product had reached. Is there a more simple solution?
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    Back pressure on a pipe by squeezing it shut

    So to calculate the nozzle diameter. I'd first need to calculate the surface tension of the liquid using; S = (ρhga/2) Then re arrange your formula above to give d Is this correct?
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    Back pressure on a pipe by squeezing it shut

    The reason for the rollers is that there are four of these dosing units fed from a manifold which is higher than the dosing units. Although there is no applied pressure from the pump on the product it seemed to drip out more freely due to the amount of product in the pipeline going back to the...
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    Back pressure on a pipe by squeezing it shut

    For some reason it has flipped the photo while uploading the left side is the sump side, this is not left to right but actually top to bottom. Left side is where the product is delivered to via a servo drive so an exact cc is delivered. The PLC then triggers the rollers to actuate and close...
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    Back pressure on a pipe by squeezing it shut

    Hopefully this works.
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    Back pressure on a pipe by squeezing it shut

    I quite possibly didn't explain myself very well so I have drawn it up. Would the roller rotating upwards and closing the pipe work create a backwards pressure to hold the product below the rollers within the nozzle with enough force to stop that product dripping out? There is no mechanical...
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    Back pressure on a pipe by squeezing it shut

    Hi all, I'm new to the forum and was after a bit of guidance. At work we are looking into purchasing a new dosing unit, however I'm unsure if the design that has been drawn up is going to work. The units design revolves around the principle that a flexible tube is compressed closed by...
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