By Colin Rice
Colin Rice Exploration Drilling Advisory - www.colinrice.co.za
One often sees guards placed on drill rigs that are either totally inadequate or are totally over engineered. For a guard to be effective it must be purpose designed and manufactured from appropriate materials.
This is the third article in Part 1 of our Technical Series on Guarding and Safeguarding. Click here for an outline of the entire Technical Series on Guarding and Safeguarding.
The previous article discussed the components of a drilling operation that should be guarded or barricaded. This article discusses the design and construction of these guards and barricades.
The design and material of construction of a guard will depend, to a very large extent, on the purpose of the guard. Guards are erected for three purposes:
to prevent a person from making contact with a moving, rotating or hot component, or,
to prevent a part of a failed component impacting a person, or,
for both of the above.
Given these three possibilities, we can now begin to define what the characteristics of a good guard are – I suggest that a good guard would have the following characteristics:
The guard must be manufactured from material that will allow the guard to adequately meet its purpose, (a guard to prevent a person from touching a rotating part of a machine can be made from relatively light gauge material but a guard to prevent a failed drill rod for example, from impacting a person would be made from very much stronger material).
When in position, the guard must still allow visual access to the component being guarded.
The guard must be removable – we cannot weld a guard to the drill rig or any other piece of equipment.
A guard must only be removable using a tool (a spanner, screwdriver or allan key). The method of attaching and securing the guard cannot be a clip or a bolt with wing nuts for example.
Barriers, or barricades, are generally set up a distance away from a machine to prevent access to an area of the drill site and so must be of dimensions and of a construction that ensures that they can effectively meet their purpose. For example, barrier tape can be used to demarcate an area of the drill site but is completely ineffective in preventing a person or animal from falling into an open sump. These areas should be barricaded with “hard” barriers” such as fencing.
Barriers must however also be easily portable so that they can be readily transported from one site to the next. They must therefore be robust enough that they can tolerate constant packing and set-up cycles yet they must be light enough that they can be easily transportable.
With the above in mind let’s look at some examples of guards and barricades – both good and bad.
Take a look at the next article in this series for some examples of a range of barriers and guards.