Boxcomp Program Help
Boxcomp is a compression estimation program for corrugated packaging. Boxcomp is provided here to aid you in assessing the optimum board grade for your pack. The standard RSC (Regular Slotted Case - FEFCO 0201 style pack) without hand-holes or other perforations is the default style. By editing the program code you are able to add any style to Boxcomp's style drop-down menu.
Every effort has been made to make Boxcomp as accurate as possible, however, due to the wide range elements that can effect a pack during its distribution cycle, no warrantee is either given or implied for the results provided by the program. As always, empirical testing prior to manufacture is recommended. Also please note the information on general accuracy of the McKee formula, given elsewhere in this file.
This program is set up to calculate the compression flute perimeter for R.S.C. / 0200 series FEFCO styles as a default. The program can also calculate the compression strength of any pack design. This is achieved by changing the flute perimeter figure (see below) to match that given by the design you wish to model. The most accurate method of doing this is to compression test a number of packs in a know grade and then use the program to calculate different perimeter values until the one which matches your result is found. A quicker, but less accurate way is to add up the size of the various vertical flute wall, in the made up pack and use that figure.
The flute perimeter is the figure calculated from the various vertical flute walls, that are in the made up pack. This is set in the "Edit Style" feature. For an 0200 series FEFCO style this is typically the length X 2 plus the width X 2. The calculated figure may be overridden during the calculation by putting a tick in the Override box, in which case the value typed into the Perimeter text box is used instead.
This is indicates the units of measurements which the program will use. When Metric is selected the paper grades will be shown in grammes per square meter, weights will be shown in kilograms and measurements will be shown in millimeters. When Imperial is selected the paper grades will be shown in pounds per square foot, weights will be shown in pounds and measurements will be shown in inches.
Enter the weight of the pack when it is full with product.
The total number of packs, including the bottom pack, which are stacked on top of each other.
The total length of time that the packs are stacked on top of each other.
The total number of pallet units or unitized loads that are stacked on top of each other.
The weight of pallet or unitizer used, if the stack contains more than one. Typical weights for standard pallets are 20 Kg or 44 lbs and 34 Kg or 75 lbs.
The percentage of print coverage on the pack.
The maximum relative humidity conditions to which the packs will be subjected. This figure will typically be between 70% and 90%.
The Percentage reduction for the various handling types: Machine, Semi-Machine and Hand. Machine handling usually causes the least amount of pack damage and Hand type handling causes the greatest CFL reduction.
Distribution - The percentage reduction in CFL that you want applied for each stop in the distribution chain. An accurate figure will usually require quite a bit of research on your distribution chain.
Some products are capable of supporting some and occasionally, almost all, of the weight on the pack. These products are typically cans and bottles. The additional strength of these packs can be factored in by selecting the appropriate figure for whatever the product will support.
The pattern in which the packs are stacked, either in column format, with the walls of one pack directly on top of each subsequent one. Interlocking stacked packs do not have their walls stacked directly on top of each other, but offset in the manner of bricks in a wall. The latter provides a more stable load in transit, but the former makes better use of the pack's compression strength.
This is the figure with which the initially calculated compression strength is multiplied to give the case failure load amount that the Boxcomp program tries to match or surpass. This figure is set at 2 as standard, less sophisticated programs use a safety factor of 5, but this is unnecessary with Boxcomp. The safety factor should be raised in relation to the amount and known accuracy of the information you are giving the program. Export packs will often benefit from a slight raise in the safety factor.
The grade safety factor is the safety factor that the calculated grade provides and should be compared against the safety factor the program has been asked to look for as a minimum. Sometimes a grade that provides a figure slightly less than two will suffice. A grade with a safety factor of less than one will lead to certain collapse of the stacked packs.
This option enables the user to factor in the effects of the distribution chain on the pack. Please note that it will require considerable empirical data gathering and research to accurately gauge the percentage drop in compression strength per stop in a particular distribution chain. The 2% shown as a default represents a relatively arduous pack distribution cycle.
The Unitizer Size drop-down menu enables you to choose from a list of the most popular unitizers sizes. The pack's outside (External) sizes are shown in the text boxes to the left of the drop-down menu. These outside sizes may be amended if necessary. N.B. This feature is not fully implemented and so is largely redundant in the current version.
Required Case Failure Load
This is the minimum compression strength that Boxcomp has calculated the pack will need to be able to withstand. The figure is shown in the weight units chosen in the "Units of Measurement" drop-down menu. The Required Case Failure Load is used to calculate the grade safety factor, which should be compared to the chosen Safety Factor. Any grade which is not at least the equal of the chosen Safety Factor should not be used without careful consideration.
The Recommended Grade and indeed ALL grades in Boxcomp are shown in the form:
Burst Value | Edge Crush Test | Liner and Fluting weight and type
Burst Value : The Mullen burst test value is shown in the first section of the grade display. When using METRIC units the burst value is shown in Kilo Pascals and is an exact value. When IMPERIAL units are in use a nominal figure is shown in Pounds per square Inch. The grades indicated will all provide a minimum of the stated burst value.
Edge Crush Test : The Edge Crush Test value is shown in the second section of the grade display. When using METRIC units the Edge Crush Test value is shown in Kilo Newtons per Meter. When IMPERIAL units are in use the figure is shown in Pounds per linear Inch.
Liner and Fluting weight and type : The Liners and Fluting are shown in the last section of the grade display. When using METRIC units the Liners and Fluting are shown in the format:
single wall material.
300K/105FR/115T/105FR/280T/BC for double fluted material.
The weight values (115, 300, etc.) are shown in Grammes per square meter.
When IMPERIAL units are in use the figures for weight values (24, 69, etc.) are shown in lbs per 100 square feet:
24K/26SC/24K/B for single wall material.
42K/26SC/24K/26FR/69K/BC for double fluted material.
The material types are shortened as follows:
K = Kraft
T = Test
FR = Fully Recycled fluting medium
SC = Semi-Chem fluting medium
Break down of the material's make-up:
| | | | | |
Outer Liner | | | | Fluting type
Fluting Types are shown last in the board material's make-up. If the material is double fluted then the outer type shown is shown first. Therefore, in the above example the "B" type is the fluting medium laminated to the Outer Liner. Common fluting types are as follows:
A = A flute, approximate flute caliper 6mm / 0.24"
B = B flute, approximate flute caliper 3mm / 0.12"
C = C flute, approximate flute caliper 5mm / 0.2"
E = E flute, approximate flute caliper 2mm / 0.08"
The fluting types where given there designations as they were developed, which is why they do not appear to run in order. "D" has now been completely superceded by "E" flute.