Cargo securing for the economically minded
The primary objective of cargo securing
is to control the cargo in a way that stops it starting to move
This is post number 30 in a series of cargo securing advice and useful hints to assist in promoting safer operational conditions.
Once a load is allowed to start moving it becomes virtually impossible to stop it turning into some kind of battering ram!! Very often the cargo pack can be higher than the front bulkhead. The cargo is often set at a distance from the front bulkhead due to perhaps weight distribution reasons. In either situation there will be open space in front of the cargo where it will not be contained and be free to move. Top over ‘friction’ lashing straps will work well with many types of cargo but directional lashing need to be added for some loads.
If the load comprises steel pipes or rods and only top-over friction lashings are used then there is a very definite danger that some elements within the load will start to move when the vehicle slows and or brakes are applied. This is due to the Friction coefficient of metal surface being quite low, around 0.2. Low friction coeffivient directly limits the ability of top-over lashings to apply sufficient lashing force. It is essential to lock together and retain all the elements within the structure of the cargo pack. Even if the top layer or corners of the cargo stay in place some of the other elements within the structure of the load may be free to move due to a low friction coefficient between the cargo elements.
Example of FIX Steel, a direct lashing system for heavy objects.
In the photo the yellow strap is an indipendent top over lashing strap not connected to the fabric. The red straps are integral parts of the FIX Steel direct lashing system.
For example, sheet metal, girders, timber, machinery are challenging loads to secure. Some form of additional restraint is therefore required to stop and block the cargo before it can start to move. Possible solutions include direct lashing methods as the FIX example shown above. Alternatively use temporary bulkheads that are suitably load rated and position them immediately infront to the cargo. You can also block cargo movement with pallets. Of these three options direct lashing offer the greatest flexibility. It can accommodate a wide range of varying load positions. Direct lashing is easy to install – fitting directly to the load and attach to standard deck mounted lashing points. It can also be stowed away when not in use. All cargoes need to be assessed individually to ascertain the possible danger that they may represent to enable selection of the correct securing system.