The stability of a folding box is determined by its material thickness and structure. Representative outer packaging requires only thin cardboard and simple plug-in connections. High-strength cardboard transport boxes, such as moving boxes, rely on more robust materials and an adapted design.

The traditional way of closing a box is the double flaps on both sides with gluing by glue or tape. An automatic bottom can increase the efficiency of the construction, but it also has its price. The push-fit bottom is a favorable intermediate step between these two construction methods. It is particularly suitable for medium-weight and possibly also heavy contents.

What is a plug-in floor and how is it constructed?

A plug-in bottom is not glued and it does not unfold automatically during assembly. It is the closure method for the bottom of a box and is put together in a few simple steps. There are two different constructions for this.

The plug-in bottom for normal folding boxes consists of four differently shaped flaps. On the long sides, a C-shaped flap and a trapezoidal flap with an attached rectangle face each other. The side flaps are irregular pentagons with slanted sides. They have a mirror-inverted structure.

The side flaps are folded in first. Then fold in the C-shaped long flap. Finally, insert the tip of the trapezoidal flap into the recess of the opposite flap.

A trained employee can assemble a carton with a push-fit base in just a few seconds. What is particularly advantageous about this design is that it can also be easily unfolded again. To do this, the center is pressed in until the trapezoidal tab slips out of the C-tab.

The flaps can then be folded up and the box folded back together. Moving boxes also have a push-in bottom. This one has a completely different structure. The flaps on the short side are split in the middle to create four narrow strips.

The tabs on the long side have a fold halfway. First, the narrow double strips are folded in. Then insert the halves of the long flaps into the slot. Then turn the moving box around and fold in the protruding ends of the flap.

The flaps still have a stiffening effect, so that they reliably bring the carton into shape. Enclosing the side flaps gives the carton base a triple thickness. This makes it particularly stable.

If an even higher load capacity is desired, you can additionally stabilize the bottom with an inserted reinforcement bottom. It can then be carried hands-free without the heavy contents breaking through the bottom.

However, remember not to load the box too heavy so you can still carry it. Your back will thank you.

The assembly of moving boxes is more complex than that of normal push-floor boxes. However, a trained employee can also do this in a few seconds.

What are the advantages of the plug-in bottom?

The plug-in bottom has the following advantages:

• Assembly possible without glue or tape
• easy assembly
• High load capacity

Assembly without additional tools or aids makes the plug-in bottom carton almost as efficient as the carton with automatic bottom. Few additional handles are required for its assembly.

This makes assembly slightly more time-consuming, but still much more efficient than cumbersome handling with adhesive tape. By eliminating the need for gluing, the plug-in bottom carton is also cheaper to produce.

The assembly of plug-in bottom cartons is child's play. With a little practice, it is done in a few seconds. This also applies to the particularly robust moving boxes.

Correctly mounted, a normal plug-in bottom has a self-wedging design. If it is loaded from above, the tabs press more firmly into each other.

The peg bottom of moving boxes is even more stable and can not break or crack in normal use. The peg bottom design is particularly suitable for medium and heavy loads.

How to properly assemble a plug-in bottom?

A normal plug-in bottom is assembled with the following steps:

1. Unfold box.
2. Fold the tabs of the cover loosely inward.
3. Turn carton over so that the bottom side is facing up.
4. Fold in short side flaps.
5. Fold in the C-shaped long flap.
6. Fold in the trapezoidal long flap.
   
7. With a slight pressure on the rectangular tip of the trapezoidal long tab, it slips under the recess of the C-shaped tab.
8. Turn carton over, fill and seal.

Moving boxes are built as follows:

1. Unfold the box and fold the flaps of the lid inwards.
2. Turn the carton with the bottom side facing up.
3. Fold strip-shaped, lateral double flaps horizontally inward.
4. Insert a long tab through the slot of the double tabs.
5. Repeat the process with the opposite long flap.
6. Turn carton over.
7. Fold the long flaps outwards and press them in firmly.
8. Press in finger holes, fill carton, label and seal.

The construction of the top of pegboard cartons is completely different from their bottom. The lid has only a sealing function, which is to prevent the contents from falling out.

For this reason, you must always pay attention to the correct carrying direction when transporting removable floor boxes. In the case of moving boxes, this is determined by the handle holes. If it is no longer clearly recognizable in the finished box, you can mark the carrying direction with a "Here above" sticker.
 

In the case of cartons with a removable base, you must pay attention to the correct carrying direction when setting up the carton!

For which products and industries are boxes with tuck-in bottoms suitable?

Cartons with automatic bottom are quickly assembled, but this bottom quickly sags under loads. Therefore, these packages are usually reinforced on the inside with an additional cardboard sheet or on the outside with a pallet.

Plug-in bottom cartons, especially moving cartons, are designed to hold their shape without additional external reinforcement. This makes this type of carton ideal for loading medium-weight products when the carton is still to be moved manually afterwards.

In Europe, this is regulated by the "Regulation on the implementation of individual EC directives relating to the EC Framework Directive on Occupational Health and Safety" in Article 2, where the "Load Handling Regulation" is found. This specifies 20 kg as the absolute maximum with which an adult man may lift and move a load by hand without aids.

For a regular load, an upper limit of 5-10 kg for women and 10-15 kg for men is allowed.

For the plug-in bottom carton, it follows that in exceptional cases it should be loaded with up to 20 kg, but as a rule with a maximum of 10 kg. This makes it still portable by hand without the need for additional lifting equipment.

This high load-bearing capacity makes the plug-in bottom carton ideal as an outer packaging with smaller containers. These can in turn be filled with the efficient automatic bottom cartons. The outer packaging absorbs the pressure loads so that they can no longer deform.

When filling the tuck bottom cartons, the volumes of both containers should be matched to each other so that as little space as possible is lost. At the same time, the maximum weight should not be exceeded even when seamlessly filling the tuck-bottom carton.

When the 20 kg limit is exceeded, lifting equipment becomes necessary. For cartons, this usually means palletizing. Cartons can only be lifted to a limited extent by tongs due to their limited lateral rigidity.

Hooks and eyelets on the top are also ruled out because the cardboard paper cannot support point loads. However, with the use of pallets, the stability of the bottom of plug-in bottom cartons becomes superfluous.

This shows that the efficient use of tuck-bottom cartons requires some planning and design. Used optimally, however, this type of carton is a valuable contribution to the efficient handling of series products of all kinds.

No matter whether in landscape or portrait format, large or small, from one box or the other. If you have any questions, please feel free to contact us.

What are the alternatives to the push-fit floor?

Plug bottom cartons are one of many types. It offers specific advantages that do not exist in other types. If these advantages are not mandatory, a peg bottom carton can also be replaced by the following alternatives:

• Standard folding box with gluing
• Ready box with glued base
• Automatic floor
• Single carton with insertable tabs.

Standard folding cartons with gluing offer similar advantages as the carton with tuck-in bottom. They have a high load capacity and are versatile. Their assembly is somewhat more complex and requires the additional use of adhesive strips. This makes the solution a little more expensive.

Ready boxes with glued bottom do not need to be built up. They come from the factory ready for filling. These boxes also have particularly load-bearing bases. Their disadvantage is that they take up just as much volume when empty as after filling.

As a result, efficiency and transport costs suffer until the time of their use. A solution to this is offered by slightly conical prefabricated boxes that can be nested. However, these again have disadvantages after filling, as they cannot be stowed seamlessly in a container.

The automatic bottom is a solution for efficient and quick assembly of a carton package. The bottom unfolds automatically and provides sufficient load capacity for many products. However, it cannot match the stability of a glued standard carton or a box with a tuck-in bottom.

Single cartons with tuck-in flaps have the advantage that you can open them on both sides. However, they are only designed for very light contents. As a rule, these cartons are transported lying down so that no pressure is exerted on the flap closure. A typical example of these carton types is packaging for medicines.

Conclusion

The tuck-bottom carton is an ideal solution for the efficient provision of particularly load-bearing carton packaging. For normal insertable trays, machines are now even available which perform the set-up automatically.

In the case of moving boxes, the boxes still have to be assembled manually up to now. In sum, the pegboard carton is particularly suitable for loads that are moved manually and reach the maximum permissible load limit of 20 kg.

For heavier loads, lifting equipment must be used, which in turn requires additional measures such as palletizing. In this way, the tuck-bottom carton closes the gap between lightweight outer packaging and heavy transport containers.

FAQ

1. How heavy can you load plug-in bottom cartons?

   The Occupational Health and Safety Ordinance sets the weight of a load for manual shifting at a maximum of 20 kg. Cartons with a removable bottom can withstand this load. This applies especially to the particularly robust moving boxes.

2. How long can you store products in pegboard cartons?

   The storage time of tuck-bottom cartons is as long as of any other type of carton that is not palletized. Palletized cartons have the advantage of being a few centimeters from the floor. This makes them less sensitive to spreading wetness. In principle, however, cartons are only suitable for long-term storage of products under certain conditions. These include low humidity and as little sunlight as possible.

3. Are tuck-bottom cartons more expensive than regular cartons?

   Plug-in bottom cartons are slightly more expensive than standard cartons of the same size and load-bearing capacity. However, they require no or much less adhesive tape for assembly. It therefore depends on the application which solution is more favorable.