Crucial and universal component of the electrical networks, the steel strap fulfills the mechanical fixing function. Used along the pole, it enables to fix various equipment and accessories. The strap adapts to all kind of pole: wood, metal, concrete, polymer, … However, several types exist, and will be explained to you…
The types of strap
The strap can be used for different applications: fixing a signing plate, a cable duct, fixing network anchoring and suspension systems and service anchoring systems or even boxes and cabinets on a pole, …
Depending on the desired use, the right choice of dimensions is important. Two dimensions are decisive for this product: width and thickness.
There are two standard thicknesses, namely 0.4mm or 0.7mm.
In terms of width, the most widely used dimensions are:
- 10 mm (3/8 ’’)
- 13 mm (1/2 ’’)
- 16 mm (5/8 ’’)
- 20 mm (3/4 ’’)
The choice of one width or thickness rather than another will mostly result of a need for greater or lesser mechanical strength. That is why preference will be given to a strap with a wide section for a high stress to hold and a thinner strap when the need is to attach an accessory to the pole without real mechanical stress.
Beyond the dimensions, the material in what the strap is made of, plays an important role when used with high mechanical stresses or with respect to resistance over time.
What material is used to make the strap?
For work on an electric pole, the strap used is made from stainless steel strips combining mechanical resistance and corrosion resistance. There are, however, several grades of steel with slight variation in chemical compounds. Thus, these variations make it possible to get a wide panel with different mechanical strengths, elongations and corrosion resistance. The grades are called “AISI XXX”. Did you know? the term AISI means “American Iron and Steel Institute”.
We can list the following shades of stainless steel, with their characteristics:
|
AISI 430 |
AISI 304 |
AISI 316 |
AISI 201 |
|
| Mechanical strength |
+ |
++ |
++ |
+++ |
| Elongation |
+ |
+++ |
++ |
+++ |
| Corrosion resistance |
+ |
++ |
+++ |
++ |
| Competitivness |
+++ |
++ |
+ |
++ |
The choice of the strap type, its width, its thickness, its steel grade, etc. will be the result of a trade-off between the application and the desired physical properties, the expected service life of the installation and the economic dimension.
How is the stainless steel strap fixed?
Once the selected type of strap fits the expectations, the suitable accessories must be chosen to allow an efficient installation.
Indeed, the strap is supplied in rolls of several meters and does not comprise a closing feature. The choice can be made between many technologies as well.
Once circled, the strap can be closed by means of those types of accessories:
- Seals,
- Buckles,
- Reinforced buckles.
The installation technique is the only criteria that helps to choose between one closing accessory or another and mainly based on the fitters’ habits. Size variations corresponding to the straps’ width ensure optimal compatibility during installation.
Beyond the closing accessories, we will also mention meshes, protective tape or anti-climbing spikes.
- The meshes are used to guide conductors along a pole.
- As for the protective bands, they are used to protect the conductors when they are held to the pole by the strap itself.
- Finally, the anti-climbing spikes are used to prevent potential fraudsters from climbing the pole.
Once the system is chosen, the next step is to implement it.
How is the strap installed onto a pole?
To implement the strap, the fitter will use:
- A shears to cut the strip to the desired length,
- A binding tool to tighten the strap around the pole,
- A hammer to fix the buckle.
The winder in which the strap is stored is also an accessory because it allows ease of unwinding and installation.
Do you want to see the use of tools and accessories and the implementation of the whole strap system?
