Hey Mr Tan, regarding to your question- "the problems and constraints of Cantilever Racks used in warehouse or distribution centre".

> The cantilevel rack is less effective in space usage as it uses many number of
aisles. In a warehouse, it is most ideal to have as minimal number of aisles as
the space used of the aisles could be use to accomodate more products.

> It has low storage density. Products that are heavy in their mass, are not able to
be supported by the cantilever as there is only a limited weight allowance a
cantilever is able to endure.

Although the parallel-flange beam section is being adopted by the art since it is a more economical section for most purposes. However, the parallel flange itself is weaker than the tapered flange which creates problems in the use of the cantilever racks of the indicated type because of the increasing possibility of failure of the column flanges. While this problem is partially overcome by the design shown in U.S. Pat. No. 4,065,089 because the point of load is at the root of the fillet of the flange as compared with the tip of the flange, there are other problems created with the loading at the root fillet such as penetration failures in light flange columns from the point loading of this construction. Also, this construction is undesirable in that it is necessary to mount all the cantilever arms on the column from the top down.

A limitation of the prior art cantilever rack constructions is their capability of carrying very heavy loads. Under these heavy load conditions the prior art devices are subject to the possibility of column flange tip failure and failure of the connector between the horizontal arm and the column flange.

Unlike all the above racks, cantilever rack does not have vertical members or columns in the front of the rack to limit the width of the loads to be stored. As the name implies, the storage levels are cantilevered from a rear vertical support only.