How to determine maximum diameter & length of Roll Film with core 3 inch using Tim's Diameter Calculation

Why it will be the important things for an Engineer or Packaging Development people ? When an Engineer and Packaging Development people starts to develop a new packaging, there are not enough information about how length of the packaging roll to be determined and how weight of the packaging roll to be determined. In fact, The Packaging Development must optimize the length of the roll film to reduce down time by changes roll and the otherside, not exceed the specification of the packaging machine like a maximum outer diameter unwind unit and maximum load capasity of unwind unit.

Maximum diameter unwind unit is a maximum diameter unwind unit at certain packaging machine that varies from one another to ensure the packaging roll rotate in normal condition at unwind unit.

Maximum load capasity for unwind unit is a maximum load of the packaging material that can handle by unwind unit to ensure no damage happen causing overweight at unwind unit.

If said, Your packaging machine has a maximum diameter unwind unit is 350 mm max and max load for unwind unit is 25 kgs, for an example the packaging material that you must develop having structure like : BOPP20/ink/adh/CPP40, width of film = 160 mm, core 3 inch, thickness of core is 9 mm. From this information, you can determine how length and how weight the roll must be by following this steps and using my formula named TIM'S DIAMETER CALCULATION below.

Step 1. From the structure of film, you can get some information like :

• Total thickness = 20 + 1 + 1 + 40 = 62 microns
• Density of BOPP film = 0.91 g/cm3
• Density of CPP film = 0.91 g/cm3
• Gsm adhesive = 2 gsm ( commonly )
• Gsm ink = 1 - 2 gsm ( commonly ), 2 gsm for Full Block Design
• Weight of core 3 inch ( thickness 9 mm ) = 195 g/100 mm

Step 2. Using my formula to determine maximum length of Roll film allowed :

TIM'S DIAMETER CALCULATION FOR CORES 3 INCH :

Max length(M)={[max.diameter(mm)exp.2 - 8836 /[thickness(microns)x1.274]}

= [(350)exp.2 - 8836]/[62 x 1.274 ]

= 113664 / 78.988

= 1439 meters tolerances 1% in length

So, The Engineer and Packaging Development must determine the length of packaging roll must below 1439 meters, for an example 1300 or 1250 meters/roll.

Steps 3. The next steps is to ensure that the weight of the packaging roll not exceed the max load capasity of unwind unit. For this case, we choose 1250 meters/roll for an example from previous steps. Then, please using this formula :

For film(Kg)=[length(M)xwidth(M)xthickness(microns)xdensity(g/cm3)]/1000

For Adhesive or Ink(Kg)=[length(M)xwidth(M)xGsm(gsm)]/1000

For Cores(g)=using extrapolation for this data :

Weight of core 3 inch ( thickness 9 mm ) = 195 g tolerances 5 % in weight

For this cases :

• For BOPP Film(Kg)= [1250x0.16x20x0.91]/1000 = 3.64 Kg
• For CPP Film (Kg) = [1250x0.16x40x0.91]/1000 = 7.28 Kg
• For Adhesive (Kg) = [1250x0.16x2]/1000 = 0.4 Kg
• For Ink (Kg) = [1250x0.16x2]/1000 = 0.4 Kg

Width of cores must wider than width of film, for this cases 160 - 0 + 2 mm. We choose 162 mm.

• For core (Kg) = [162/100]x195 = 315.9 g = 0.316 Kg
• Total weight (Kg) = 12.04 Kgs

So, The Packaging material roll for 1250 meters can be applied because the weight of the roll = 12.04 Kgs, not exceed the max load 25 kgs, and the maximum outer diameter roll not exceed the maximum outer diameter unwind unit. Good Luck !!

Adding information for density of the packaging material :

Material Density (g/cm3)

Aluminium foil 2.72

PET 1.4

PVC Shrink 1.2

Nylon 1.15

LLDPE 0.92

BOPP 0.91

CPP 0.91

PVdC 1.7

Note : For next articles, I will give another formula to determine the same cases like it, but using different diameter cores such as core 4 inch and 10 inch. Commonly used in Pulp & Paper Industry.

From the author :

Hopefully, this articles usefull for You. Well pleased to sent this FREE information to any people and let Anytime, Anywhere, and Anypeople using this site : http://www.interpak.blogspot.com/ as a references for Packaging & Printing Issues.

Regards,

Mr.Timothy

Marking Code for Plastic part II

This International Code has been made just only for two reason :

• To know the kind of plastic to be used


• To prevent Hazard that happen from uncontrolled using

This International Code has been socialized by The Society of Plastic Industry in 1988 at USA and any other Organization like International Organization for Standardization ( ISO ) has adopted it.


How to check The Code :

1. The Code placed at the bottom of the packaging
   


2. The Code appears as a triangle form



3. There is a number at the center of the triangle



4. There is a type of plastic to be used below the triangle



5. There is a seven number and add with three more number addition, so totally there is a ten number for The Code
   

Properties :

The plastic with This Code number 1 with GREEN color, made from PETE or PET ( Polyethylene Terephthalate )

• PET plastic not stable in warm to hot condition. The skin of Polymer will be damaged and changes to be a Carsinogenic particles that causing a cancer for longterm. Not recommended to be used for warm to hot liquid.


• Transparent appearence, good in clarity
  

Hazards

1. For PET Bottle Plastics not recommended to be re-used. Hazard of Toxic


2. People who works in Plastics Industry specially in PET Plastics must be aware for The Dust of Polymer that carry Anthimony Trioxide particles that hazard for :
   

• Skin irritation and breath respiration system


• For Children, making slow growth till 12 months


• For Women, making unstable for menstruation cycles

Commonly used

• 30% capasity PET plastics in the world used for Platics Bottle


• 60% capasity PET plastics in the world used for Textil
  
  
  
  
  
  
  
  
  

Code number 2 with GREEN color, it's meaning for HDPE ( High Density Polyethylene ) material
Properties :

• Clarity not as good as PET material
• Good in heat resistance
• More stiff and stronger than PET material at the same thickness

Hazards :

Not recommended to re-use because the Anthimony trioxide still released from HDPE resins as long as period of using

Commonly used :

• For milk, water, and any other container for food and drink
• So far, safely for food either in warm condition

Code number 3 with RED color, it's meaning can not recycleable. Code " V " it is meaning for PVC ( Polyvinyl Chloride ) Material.

Properties :

• Good in clarity
• Specifict plastic smell

Hazards :

PVC material contains DEHA that contamined the product packed like food and drink by direct contact through the surface of the PVC film. DEHA melting at -15oC. The product contamined not save for human that causing damage in Kidney, Lever, and any other organ complications.

Commonly used :

For wrapping product ( cling wrap ) such as food wrap, souvenir wrap, PVC Shrink for FMCG Industry, etc.

Code number 4 with GREEN color, it's meaning for LDPE ( Low Density Polyethylene ) material.
Properties :

• Strong
• Clarity not good, rather opact appearence
• Good in flexibility
• Not react with other chemical agent at temperature below 60oC
• Good in water vapor resistance
• Not good in Gas barrier

Hazards :

Not recommended to re-use because the Anthimony trioxide agent still released from LDPE resins as long as period of using.

Commonly used :

For drink and food container

Code number 5 with GREEN color, it's meaning for PP ( Polypropylene ) material

Properties :

• Good in Gas barrier
• Glossy appearence
• Stiff and strong enough
• Good in Fat and oil resistance
• Good in heat resistance

Hazards :

No hazards found, very recommende to use this material to package food and drink product like milk, water, etc. Look for this code below the packaging and ensure it before buy !!

Code number 6 with RED color, it's meaning for PS ( Polystyrene ) material.
Properties :

• Not strong
• Not Stiff
• Unstable material
• Not good in heat resistance

Hazards :

Polystyrene is an aromatic polymer that can release styrene material through direct contact to the food or any other product packaged. You can found styrene also in ciggarete smoke, vehicle smoke, and any construction material building.

Not safe for transmission system for Brain, reproduction organ in women, body growth for children, etc.

Commonly used :

Used as a styrofoam ( food container ), construction material building, etc. This material was founded by Eduard Simon in 1839, Germany.

Note : If there is no code number 6 founded below the packaging, you can identify this kind of material by burn the material and see the flame will give a color yellow-orange.

Code number 7 with RED color with " OTHER " word, it's meaning for four ( 4 ) material category like :

• SAN ( Styrene acrylonitrile )
• ABS ( Acrylonitrile Butadiene Styrene )
• PC ( Poly carbonate )
• Nylon

Properties :

• SAN & ABS good in heat resistance and chemical resistance
• Good in stiffeness
• Good in tensile

Hazards :

• SAN & ABS recommended for food and drink container
• If there " PC " word below the code number 7, not recommended for Food and drink although so many product in the market using this material today. Be Carefull ! ensure not to use this material because causing organ damage in chromosome, sperm, imunity system, etc.

TIPS for YOU !

• This code of material safe for You : Code number 2 , 4 , 5 , and 7 ( SAN & ABS )
• Not recommended to use palstic packaging that using Top print / Surface Print that can contaminate the food and drink packed. Ink produced from mineral and any other heavy metal like Pb ( Lead ), TiO2 ( Titanium Dioxide ) that causing carcynogenic desease.
• Stainless steel container, Glass bottle, plastic bottle code number 4 and 5 safe for Baby milk container
• Plastic nipple made from latex and plastic code number 7 ( PC ) not recommende used for Baby
• Not recommended to keep material plastic with code number 7 ( PC ) in hot condition
• Not recommended to re-use PET and HDPE bottle for longterm using even in cold condition like in refrigerator. Replace with using Glass or Stainless Container
• Not recommended to keep warm the food package inside plastic container using microwave. Recommended using banana leaf to package the product surroundly before placed on the plastic container inside microwave
• Not recommended to use a plastic for food plate. Replace by using Stainless Steel, wood, Glass, and Ceramic plate

What is plastics ?

Plastics is an aromatic polymer that derivaded from Natural Oil. Plastics contain Bisphenol-A, a toxic material that causing damage any organ like breast, lever, kidney, brain, reproduction organ in men and women. University of Missouri has already surveid the market and Bisphenol-A founded in 5 most brand baby milk bottle like : Avent, Dr.Brown's, Evenflo, Gerber, and Playtex !!!

Plastics already consumed more than 100 million tons a year in the world, and Amazed ! more than 95 % of total popularity in the world ever used plastic that contain Bisphenol-A.

There are two kind of plastic in the public market :

• Thermoplastic, this type will be melt in heating
• Thermosetting, this type can not melt even giving heat, and still hard after heating

How plastics influenced your health ?

• PVC plastic has a properties stiff and rigid. To make more soft, any plastic industry giving Plasticizers like ESBO ( Epoxidized Soybean Oil ), DEHA [ di(2-ethylhexyl)adipate ], PCB ( bifenil poliklorin ). Platicizer like PCB already prohibited because causing cancer for human, also for DEHA and ESBO ( commonly used as an additive for insectiside )
• Don't ever burn the plastic specially PVC. The smoke causing infertility for organ production even for men and women.