The idea of foldable containers is not so new. In the past several designs have been proposed. The majority of these ideas however never passed the phase of patent granting. Only two concepts have achieved the phase of pilot/testing and market introduction and are currently still available: the Six-In-One container and the Fallpac container.

Six-in-One container

The   Six-in-One   (SIO)   container is a fully dismountable 20ft   dry freight box that  once dismantled,   can   be   folded,   stacked six high and interlocked to the   exact   dimensions   of   a standard 20 ft x 8 ft x 8 ft 6in container. It was launched about sixteen years ago by Six-in-One Container Co (SCC),  a Swiss concern with a marketing base in  France. Since introduction about 2000 units have been manufactured. A shortcoming of the first series of the   SIO   was   its   maximum   gross   weight  of   20   tonnes,  while   standard   boxes   have   a   gross weight of 24 tonnes. In the next generation, the carrying capacity was increased to 24 tonnes, which left only one significant difference with the standard 20 ft container: the higher tare weight, which is about 500-600 kg heavier for the SIO.

The most striking characteristic of the SIO is the absence of hinges, other than the standard door   hinge.   The   SIO   incorporates seven separate elements  with locking  devices.   Simple production  and  reduced manufacturing costs were   important motives to  choose  for  this construction based on dismountable parts. Avoiding the use of hinges was believed to be a key factor for success,  because   of   well-known   problems   with   hinges   (i.e.   corrosion,   frost, bending).

In figure 1 the main steps of the (un)folding procedure are shown. To fold a container a three-person   team   with   a   forklift   is   required.   SCC   claims   this   process   takes   approximately 15 minutes. To simplify and speed   up   the   mounting/dismounting  process   an   assembly  jig  was designed, enabling handling productivity to increase from four to six containers per hour. Initially,   SIO   containers   were   only  available   for   sale.   In   order   to   market   the   product   more successfully,   containers   could   also   be   leased   from   the   early   1990s.   In   addition,   the   SCC company   was   willing   to   organise/operate   the   assembly   and   dismounting   processes.   In   this way containers could be delivered erected to the shipping line user, so the customer would notice almost no difference in using a standard box or SIO container.

Although about 2000 SIO containers have been produced – of which the  actual number of units still in operation (i.e. being mounted and dismounted) is unknown – one can not speak of a great success.   Their market share is far too small compared to conventional  container volumes.

To find out the reasons for the lack of market penetration, several experts were interviewed, including representatives of companies that used the SIO. Practical experiences demonstrate that   particularly   the   costs   of   folding   and   unfolding   the   container   are   a   strong   barrier.   In practice   folding   and   unfolding   takes   far   more   time   than   claimed   by   the   manufacturer.   To insert the walls and doors is a time-consuming and difficult process, particularly when parts are slightly damaged.

Vulnerability   to      damage     proves    to  be   a  serious   concern     for  potential    users,   particularly because   these   kind   of   containers   are   often   used   in   areas   where   containers   are   usually   less carefully handled. In addition, theft of container parts is   a   serious   problem   in   certain   areas (i.e.   Third   World   countries).   According   to   companies,   susceptibility   to   damage   and   theft make this system vulnerable. Furthermore,   companies   are   of   the   opinion   that   the   purchase   price   of   the   SIO   is   too   high. Compared with the standard box prices, which have dropped enormously over recent years, the   SIO   is   about   3.5   times   more   expensive.   However,   one   can   debate   this   argument   by considering the exploitation costs of the container in relation to the total costs of the container logistics.

Last   but   not   least,   problems   may  arise   regarding   the   integration   of   the   SIO   in   the   existing logistic chain. Most striking are the equipment problems existing container depots might have in handling a bundle of SIO containers, whose handling requires more time and space.

Fallpac container

The     folding   technique     of  the   Fallpac   container    is  quite   different   from    that  of  the   SIO container. The Fallpac is a 20 ft dry freight box which combines dismountable and collapsible features. The roof of the container is dismountable, the remaining elements are foldable. Four folded units can be stacked inside a fifth assembled unit for empty transport (see figure 2). In this way the Fallpac container has also the same dimensions of the 20 ft standard box. The maximum gross weight of the Fallpac container conforms to ISO standards (24 tonnes), but   its   tare   weight   is   approximately   4000   kg,   which   is   about   1700   kg   heavier   than   the standard 20ft container.

To   fold   or   unfold   the   container   two   people   and   a   forklift   are   required.   According   to   the Swedish manufacturer (Fallpac AB), the box can be folded within 10 minutes. Because the folding technique incorporates folding side doors, the container is suited for side loading as well as end loading. In the original design there was a problem with leakage through the side doors, but this has been solved in the more recent design.

The first Fallpac container dates from the mid eighties. Since then some design changes have been introduced. In addition to the basic design a prototype of a fully-automated version has been launched recently. For the manual version   a   small   test   series   of   containers   have   been produced   and   tested   with   customers,   including   Swedish   Rail.   These   tests   took   place   many years by now and did not result in succession. Technical problems or serious disadvantages have not been reported, except its high tare weight. Serious problems with the hinges have been reported neither. The successful flat racks might have served as a good example for the folding   technique   that   has   been   chosen.   However,   experiences   with   the   Fallpac   have   been small-scale.

The high tare weight might be an obstinate barrier itself, particular as it comes to transporting and handling a bundle of empty containers. This indicates possible problems of integrating the container in existing logistic processes: this seems not only a problem for the Fallpac, but for the SIO container too. Last but not least, it seems that the very limited application of the Fallpac can be attributed to little marketing and insufficient promotion of the distinct features of the concept.

2 3