How does hose lenght effect vacuum?

[knighty]

Anyone know much about vacuum hose and how it effects the air pressure/suction/vacuum/whatever ?

New thermoformer going in at work, imagine a machine making packets of bacon but they're vacummed flat 6 at a time.

The vacuum pump is pretty big/noisy so I'd like to mount it further away from the machine but I've got no idea how line lengths effect a vacuum. Googke results are all scientific stuff not real world results.

I'd like to run short flexi from pump to about 8m of hard plastic tubing, 90' bend, 1m of hard then flexi to the machine

Would be nice to have an idea if it'll work before I do it all!

Flex on the pump right now is 65mm id

 

[minimutly]

Vacuum is like pressure (sounds silly but it's just air at relative pressure to atmosphere). So if the pump runs continuously there will be no issues. If it's start stop you will have a delay.

 

[Erie Fred]

Can you add a tank where the pump sit's now ?
Relocate the pump further away, tank handles the initial surge.

 

[addjunkie]

Vacuum is like pressure (sounds silly but it's just air at relative pressure to atmosphere). So if the pump runs continuously there will be no issues. If it's start stop you will have a delay.

Id agree with that, not sure on the flexis though, they may collapse under vacuum.

 

[Kram]

For your machine is the vacuum valved or when ready, do you just turn on the pump?

Using a valve and having the pump running in advance, it will give you more volume of vacuum and so it will have more "pull".

If your only applying the punp at the correct time, it will take longer to vacuum the extra volume and could take significantly longer to reach the desired pull. However it looks like a decent sized pump.

What is the flow rate of your pump and the volume of the existing and new systems?

 

[knighty]

Pump runs all the time, vacuum goes on/off by a valve.

I could mount a tank near to the valve, but I don't think there's enough space for a tank big enough to make a difference.

Valve is roughly open 3 seconds closed 7 seconds, repeating

I was worried about the pressure difference across the length, my thinking being airlines are ok with a few psi drop when you run 130psi to start with... but vacuum can be 14psi ish at best? (Air pressure at sea level?)

Guess work from me tho, I've never done vacuum stuff before


Ill get some high pressure 100mm tube and use that as much as I can

 

[Dozzer]

Pump runs all the time, vacuum goes on/off by a valve.

I could mount a tank near to the valve, but I don't think there's enough space for a tank big enough to make a difference.

Valve is roughly open 3 seconds closed 7 seconds, repeating

I was worried about the pressure difference across the length, my thinking being airlines are ok with a few psi drop when you run 130psi to start with... but vacuum can be 14psi ish at best? (Air pressure at sea level?)

Guess work from me tho, I've never done vacuum stuff before


Ill get some high pressure 100mm tube and use that as much as I can

Vacuum is mainly down to evacuation volume,
If you keep the valve in the same place, ie nearest the packaging station. then only the initial start up will be a bit longer.

 

[hotponyshoes]

Pump runs all the time, vacuum goes on/off by a valve.

I could mount a tank near to the valve, but I don't think there's enough space for a tank big enough to make a difference.

Valve is roughly open 3 seconds closed 7 seconds, repeating

I was worried about the pressure difference across the length, my thinking being airlines are ok with a few psi drop when you run 130psi to start with... but vacuum can be 14psi ish at best? (Air pressure at sea level?)

Guess work from me tho, I've never done vacuum stuff before


Ill get some high pressure 100mm tube and use that as much as I can

Vacuum works the same as positive pressure.
The pipe/hose causes friction with the air and reduces the flow rate.
You'll notice it in an air tool as you are constantly pushing air through and constantly loosing flow.
So 130psi at the compressor might only be 110psi at the working tool.
If you fit a pressure gauge at the tool end you'll see 110psi when the tool is running. But when you stop the tool you'll see the pressure creep up to 130psi.

Same with vacuum, a longer (or smaller) hose will reduce flow but you'll still get down to whatever the pump is capable of eventually because your chamber is sealed.
You may need to change your cycle time from 3/7 to 4/7 or something.
Easy way to test would be to add the extra length of line into the system while everything else is still in place.
Or, do the maths, I'd guess there is a caculator for it online somewhere.

 

[Bornfree]

Looks like a busch vac pump. I've still got the long lengths of feeler strip for setting the rotor clearance. Great pumps really well made.

 

[hotponyshoes]

You might want to look at the chamber venting as well, get the vacuum line valve as close to the chamber as possible then a seperate (or change-over) valve to vent the chamber.
The longer line will act as a reservoir so keep as much vacuum in there as you can and you might not need an extra tank

 

[gaz1]

Anyone know much about vacuum hose and how it effects the air pressure/suction/vacuum/whatever ?

New thermoformer going in at work, imagine a machine making packets of bacon but they're vacummed flat 6 at a time.

The vacuum pump is pretty big/noisy so I'd like to mount it further away from the machine but I've got no idea how line lengths effect a vacuum. Googke results are all scientific stuff not real world results.

I'd like to run short flexi from pump to about 8m of hard plastic tubing, 90' bend, 1m of hard then flexi to the machine

Would be nice to have an idea if it'll work before I do it all!

Flex on the pump right now is 65mm id

can i ask what is inbetween the pump to the sealer

the vacuum side of it maybe set for whats within the pipe and the box seal of the packaging

so only pulls out of the pipe and the seal system

or it comes down seals and sucks all of the air out fast and seals the bag at the same time as by what your time settings are

fitting a tank or longer length of tube may cause more suction on the food items when they are sealed

 

[hotponyshoes]

can i ask what is inbetween the pump to the sealer

the vacuum side of it maybe set for whats within the pipe and the box seal of the packaging

so only pulls out of the pipe and the seal system

or it comes down seals and sucks all of the air out fast and seals the bag at the same time as by what your time settings are

fitting a tank or longer length of tube may cause more suction on the food items when they are sealed

He said the pump runs all the time so the extra tube won't make any more suction.
It might just slow everything down a bit so he won't have enough level of suction before the cycle time completes.

 

[gaz1]

He said the pump runs all the time so the extra tube won't make any more suction.
It might just slow everything down a bit so he won't have enough level of suction before the cycle time completes.

yes i read that but with 2 ways you create more suction

both the longer length pipe and also a tank fitted will cause a better suction as more air has been pulled out of the piping/ tank system

but that can damage the food with the packaging

if they know what air was within the system after the valve and what air was within the sealing section including the pipe

then a twin valve system could be used as air would only be pulled out of the tube to match what was between the valve and the sealed bag system

 

[hotponyshoes]

yes i read that but with 2 ways you create more suction

both the longer length pipe and also a tank fitted will cause a better suction as more air has been pulled out of the piping/ tank system

but that can damage the food with the packaging

if they know what air was within the system after the valve and what air was within the sealing section including the pipe

then a twin valve system could be used as air would only be pulled out of the tube to match what was between the valve and the sealed bag system

If the pump runs all the time it's either aiming for absolute vacuum or it will have a relief valve
.
I'd be very surprised if the amount of vacuum in the packaging chamber was regulated only by the cycle time as A, it would require some tricky setting/calibration and B, be dependent on not only the full load of 6 packs being loaded each cycle but the contents of each package being the same volume which would be virtually impossible with a natural product like bacon.
Generally, with food packaging you aim to remove 100% of the air for product life. If the presentation aspect of the packaging won't support full vacuum you replace the air in the package with an inert gas like nitrogen.

 

[hotponyshoes]

I'm not clear from the op's post if he's actually packaging bacon or if this is for a machine that just makes the packaging the bacon goes into later?

 

[RichardM]

You could also look at putting the pump in an acoustic cabinet.

 

[knighty]

lots of questions answered all at once so the post isn't a mile long with quotes...

no idea on the flow rate / suction power of the pump

it's probably sucking out 3 or 4 litres of air each cycle max

valve isn't moving

the packets are formed out of a sheet of plastic which feeds along like a big conveyor, that film is punctured around the edges, a top film goes on, air is sucked out from between them through those puncture holes, then a top plate comes down clamping the top film onto the bottom and sealing them against each other (with heat)

weirdly, the machine as it came would suck from inside the packets and on the bottom of the packets at the same time... so counteracting itself.... I had to adapt it to work properly

it's packing pet food, minced meat

there's no nitrogen flushing, it's setup so we could if we wanted, but there's no need, vacuum all the air out works better for us

pump away from the area is the best way forward, stops someone steam cleaning it and killing it or hitting it with a forklift etc.


I had a terrible time after I bought the machine, bought it in an auction but guaranteed working, wasn't cheap at all... new they're the price of a nice house, used they're the price of a cheap house :-o

it was stripped down for transport, I thought I'd be proactive and get the manufacturers out to re-assemble and service it.... £1800 for one guy for 2 hours to tell me it'll take a team of engineers and week to reassemble and there's a bunch of faults with it, dead pneumatic valve block, a heater shorting out, lots of dead sensors etc. etc.

I reassembled it myself on a Saturday morning, there's nothing broken, everything works :-o

then to make it work the way I wanted I needed a password to change the settings.... it took 3 months to get that password out of them

had it all working just how I wanted it, then left it unplugged for a month while I was getting ready for it... the battery in the controller ran flat and it lost all it's settings.... they flat out refused to give me the settings or come out and enter them for me (and at this point I'd still been super nice to them)


so I gave up on them, ripped it all out re-wired it from scratch and fitted it with a new PLC and touch screen, it's been a hard slog but it's now 10x better than it was to start with

it's finally ready to use!

just need to get factory ready for it and move it... which would be easy if we weren't so busy in the factory already :-o


just found a photo and remembered I was quoted £100,000+ for a machine to take a single feed of meat, split it 6 ways and then drop it into the trays... so I did that myself too

photo is in my workshop so don't judge the mess in the background along side the meat, it was a test run, didn't sell any of it :-)

 

[gaz1]

ive looked them up and seen that they have a balance relief valve on them

your fine to fit a longer length pipe and also a vacuum chamber on it as that vacuum chamber will speed up the process for you as it will vacuum out more of the air faster from the machine as they will already be in a prevacuum state

 

[Turbo]

lots of questions answered all at once so the post isn't a mile long with quotes...

no idea on the flow rate / suction power of the pump

it's probably sucking out 3 or 4 litres of air each cycle max

valve isn't moving

the packets are formed out of a sheet of plastic which feeds along like a big conveyor, that film is punctured around the edges, a top film goes on, air is sucked out from between them through those puncture holes, then a top plate comes down clamping the top film onto the bottom and sealing them against each other (with heat)

weirdly, the machine as it came would suck from inside the packets and on the bottom of the packets at the same time... so counteracting itself.... I had to adapt it to work properly

it's packing pet food, minced meat

there's no nitrogen flushing, it's setup so we could if we wanted, but there's no need, vacuum all the air out works better for us

pump away from the area is the best way forward, stops someone steam cleaning it and killing it or hitting it with a forklift etc.


I had a terrible time after I bought the machine, bought it in an auction but guaranteed working, wasn't cheap at all... new they're the price of a nice house, used they're the price of a cheap house :-o

it was stripped down for transport, I thought I'd be proactive and get the manufacturers out to re-assemble and service it.... £1800 for one guy for 2 hours to tell me it'll take a team of engineers and week to reassemble and there's a bunch of faults with it, dead pneumatic valve block, a heater shorting out, lots of dead sensors etc. etc.

I reassembled it myself on a Saturday morning, there's nothing broken, everything works :-o

then to make it work the way I wanted I needed a password to change the settings.... it took 3 months to get that password out of them

had it all working just how I wanted it, then left it unplugged for a month while I was getting ready for it... the battery in the controller ran flat and it lost all it's settings.... they flat out refused to give me the settings or come out and enter them for me (and at this point I'd still been super nice to them)


so I gave up on them, ripped it all out re-wired it from scratch and fitted it with a new PLC and touch screen, it's been a hard slog but it's now 10x better than it was to start with

it's finally ready to use!

just need to get factory ready for it and move it... which would be easy if we weren't so busy in the factory already :-o


just found a photo and remembered I was quoted £100,000+ for a machine to take a single feed of meat, split it 6 ways and then drop it into the trays... so I did that myself too

photo is in my workshop so don't judge the mess in the background along side the meat, it was a test run, didn't sell any of it :-)


View attachment 502945

Is it made by Tiromat by any chance?

The food factory I worked in had an old machine that did a similar process to yours.
It had been in damp storage for years and they decided to recommission it. It had a lot of aluminium parts and every thing was seized up.
After working at it for a few days our workshop manager had a long list of parts required to get it running again.

After pricing up the parts the management decided it wasn't worth fixing and the machine was scrapped. The busch vacuum pump was kept and ended up at another factory.

 

[Jack_K]

Vacuum needs a nice large hose otherwise it will be restricted. Just think of it as low pressure.

When vacuuming refrigeration systems, it is common to fit 3/4" hoses instead of using the typical 1/4" ones. It makes the process a lot faster. Just like breathing thru a straw.