Multiple Small Trench Shields vs Longer Trench Shields

There is a saying or phrase associated with Abraham Maslow that goes something like “When the only tool you have is a hammer, everything begins to look like a nail.”  This is true in the trench shoring and shielding world as well.    When the only tool you have is a trench shield, every job is a trench shield job, no matter how deep or how big.  When all you have is a slide rail, everything is a slide rail job, no matter how small or how large.

Looking further into this, if a market is only use to having smaller trench shields in it, say 8’ tall x 10’ or 12’ long, contractors will find a way to make due with these smaller shields.  However, let’s look at these smaller shields a little more in depth. If a contractor needs to lay a 20’ long pipe, it can be done using a 10’ long and a 12’ long trench shield, providing 22’ of total trench shield length.   This is good, the full length of the pit fits within the trench shields, allowing for crews to work in a safe area around the pipe as needed.  But as the diagram shows below, lowering said pipe is easier said than done.  To do so, the pipe would have to be snaked in the shields, under the spreaders in the middle, severely cutting into a crew’s productivity.

Small shields

 The reasoning for using the smaller boxes is a valid one, not every crew has access to the larger machines commonly found in the United States.  In Latin America for example, the most common size machine is a 20 ton excavator.  For that size machine, the use of these smaller shields makes sense, as such; the market is flooded with them.

There is an alternative to this, which still provides crews with a safe working area, while allowing them to use the same, 20 ton excavator is to use a longer shield.   Pro-Tec Equipment is able to achieve this combination of shield length and reduced weight, while still bearing a usable depth rating.

Long Shields

 

With a shield of this length, crews are able to easily lower the 20’ pipe into the shield without having to snake it around center spreaders, increasing crew efficiency and productivity, while still providing a safe working environment.  

Interested in more information?  Contact Pro-Tec Equipment here.