Improving the system/reducing downtime

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Improving the system/reducing downtime

Postby Flexforlife » Fri Mar 01, 2019 12:27 pm

Hey guys! This is my first post and i have a lot to know and ask! Promise the next ones will be a lot shorter :smile:

I just have a couple of questions (more than a couple :wink: ) that would really benefit the company im working in. At the moment, the company is struggling to put a system especially in the printing department (out of 3 other departments) we work in polyethylene , polyester and BOPP.


So.. the main problems(P) that are causing downtime are as follows:

P1- We a lot of damaged aniloxes. Mostly vertical cuts and bumps that appear with every anilox rotation
P2- Some aniloxes are blocked therefore ink transfer rate is reduced. We have a laser cleaning machine but they say it damages aniloxes so it can only be used once every 6 months. Is this true?
P3- Operator has to visually check each plate to know which unit to place it in, knowing that each plate has the color written on it (Ex: Magenta plate has magenta written on it and the order file says magenta should be in unit 3 so operator places magenta in unit 3).
P4- Each doctor blade chamber has two tubes at the top of the chamber. When the return valve is clogged these tubes let out excess ink that is not returned to the bucket which causes the Ink to start spitting from those tubes at high velocity dirtying the machine and wasting ink.
P5- Doctor chamber explodes spilling ink all over the machine (Usually happens with highly viscous inks like white and gold)
P6- Operators dont know how to solve some of the problems. Through trial and error they keep wasting resources until the problem is solved without knowing what the defect and the root cause of the problem are
P7- Sometimes we have to stop production because a line of ink appears between each bag and the other (We call it joint but i dont know what the term is). Usually happens after cleaning

My questions(Q) are:

Q1- What causes damage in aniloxes and how do i prevent it?
Q2- What is the optimal anilox system? Are aniloxes arranged according to the order being printed or aniloxes for every machine?
Q3- How do the operators usually know which plate goes into which unit? Do you order the plates according to the unit they will be placed in? Labels on carts?
Q4- How do you solve the problem that happens in P.4?
Q5- How do you prevent doctor blade chamber explosion? Do you change the blade according to running time? Is there another way to prevent it?
Q6- How do you usually solve problems when they occur? Trial and errror? Experience in spotting defects and knowing what causes them?
Q7- Ink lines that appear between bags? Did it ever happen where youre working?

Thank you in advance!!
Flexforlife
 
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Re: Improving the system/reducing downtime

Postby donaldwal » Fri Mar 01, 2019 6:13 pm

all operators have to learn through trial and error.... Sadly this is what divides the good from the chaff ….
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Re: Improving the system/reducing downtime

Postby longtimefan » Fri Mar 01, 2019 7:04 pm

Anilox cuts sound like score lines.. They can appear from the blades on your chambers.

Little tiny slivers come off the blades.. You can look into magnets you put in your buckets.

Also hard chunks of ink could cause same lines, and some sort of filter has to be put in your lines.
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Re: Improving the system/reducing downtime

Postby longtimefan » Fri Mar 01, 2019 7:10 pm

Water or solvent ink?

When your ink explodes? What is the viscosity?

What aniloxes are you using with those?

Are your chambers enclosed with seals on the edges?

The tubes you mentioned, are they drain hoses on each end of the chambers?
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Re: Improving the system/reducing downtime

Postby longtimefan » Fri Mar 01, 2019 7:12 pm

The lines between bags? Little confused on that statement.. Maybe you mean tracking? Rubbing off.

What type of press is this?
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Re: Improving the system/reducing downtime

Postby longtimefan » Fri Mar 01, 2019 7:26 pm

Google flexographic troubleshooting... Many pdf files to help.

Laser cleaning is recommended for 2 tiles a year is what I have heard, but ask the maker of your cleaner.

Plates, can you use an engraving tool to mark them? What you explained, seems to be the standard procedure.

Visually check blades at every clean up.. Any dips or defects change out.. When brand new, write down the date and monitor footage used. After a while can get an idea how long they can last.
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Re: Improving the system/reducing downtime

Postby Flexforlife » Sat Mar 02, 2019 8:55 am

longtimefan wrote:Water or solvent ink?

When your ink explodes? What is the viscosity?

What aniloxes are you using with those?

Are your chambers enclosed with seals on the edges?

The tubes you mentioned, are they drain hoses on each end of the chambers?


Solvent ink

The viscosity is usually between 16-19 sometimes less sometimes more depending on the ink used

Explosions usually happen when were using 170-200 cpi aniloxes.

Yes rubber seal on both sides

Yupp! struggled with the term on this one. Theyre not hoses though, more like 20cm plastic tubes
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Re: Improving the system/reducing downtime

Postby Flexforlife » Sat Mar 02, 2019 8:57 am

longtimefan wrote:The lines between bags? Little confused on that statement.. Maybe you mean tracking? Rubbing off.

What type of press is this?



Will post a picture showing the defect. But its not tracking or rubbing off

Its a Miraflex CM
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Re: Improving the system/reducing downtime

Postby Flexforlife » Sat Mar 02, 2019 9:06 am

longtimefan wrote:Google flexographic troubleshooting... Many pdf files to help.

Laser cleaning is recommended for 2 tiles a year is what I have heard, but ask the maker of your cleaner.

Plates, can you use an engraving tool to mark them? What you explained, seems to be the standard procedure.

Visually check blades at every clean up.. Any dips or defects change out.. When brand new, write down the date and monitor footage used. After a while can get an idea how long they can last.


No they usually mark them using a marker. I think ill just order them in a standard way using labels for each unit. Might save some time!

I think the blade wear will differ depending on ink density. Do I have to measure it for each color? (Some colors are higher in density than others Ex: white compared to yellow)
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Re: Improving the system/reducing downtime

Postby Flexforlife » Sat Mar 02, 2019 9:08 am

donaldwal wrote:all operators have to learn through trial and error.... Sadly this is what divides the good from the chaff ….



:(
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Re: Improving the system/reducing downtime

Postby Flexforlife » Sat Mar 02, 2019 9:16 am

longtimefan wrote:Anilox cuts sound like score lines.. They can appear from the blades on your chambers.

Little tiny slivers come off the blades.. You can look into magnets you put in your buckets.

Also hard chunks of ink could cause same lines, and some sort of filter has to be put in your lines.



Filter in lines? Can you explain a bit more?
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Re: Improving the system/reducing downtime

Postby Flexforlife » Sat Mar 02, 2019 9:34 am

Flexforlife wrote:
longtimefan wrote:The lines between bags? Little confused on that statement.. Maybe you mean tracking? Rubbing off.

What type of press is this?



Will post a picture showing the defect. But its not tracking or rubbing off

Its a Miraflex CM
Last edited by Flexforlife on Thu Apr 18, 2019 9:20 pm, edited 1 time in total.
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Re: Improving the system/reducing downtime

Postby longtimefan » Sat Mar 02, 2019 11:40 am

Those are plate lifts, or plate ups..

Seem of plate not staying down.

You can trim it off, or make sure back of plate is clean and sticky back is good
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Re: Improving the system/reducing downtime

Postby longtimefan » Sat Mar 02, 2019 11:42 am

This is one type..

What type of pumps or ink delivery do you use?
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Re: Improving the system/reducing downtime

Postby longtimefan » Sat Mar 02, 2019 11:44 am

Flexforlife wrote:
longtimefan wrote:Google flexographic troubleshooting... Many pdf files to help.

Laser cleaning is recommended for 2 tiles a year is what I have heard, but ask the maker of your cleaner.

Plates, can you use an engraving tool to mark them? What you explained, seems to be the standard procedure.

Visually check blades at every clean up.. Any dips or defects change out.. When brand new, write down the date and monitor footage used. After a while can get an idea how long they can last.


No they usually mark them using a marker. I think ill just order them in a standard way using labels for each unit. Might save some time!

I think the blade wear will differ depending on ink density. Do I have to measure it for each color? (Some colors are higher in density than others Ex: white compared to yellow)

Density shouldn't affect blade wear.. Anilox will and whites will.. Aniloxes under 550 will wear blades faster then 1000..
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