The structure of a steel pole
Although the structure of steel poles varies slightly depending on the product, the same basic principles apply to all products. A pole usually consists of an arm attached to a shaft. A pole will always have at least a shaft, which may be conical, stepped or even cylindrical. An arm or cross arm will often be attached to the shaft.
Shaft
Pylväsrakenne sisältää aina vähintään rungon, joka voi olla ulkomuodoltaan olakemainen, kartio taikka sylinterin muotoinen. Rungon lisäksi pylvääseen liittyy usein myös varsi tai orsi.
The shaft of a light pole is hollow, and is usually made from a tubular profile. The shaft can be divided into three basic parts: the base section, the top section, and the connection cabinet or handhole.
The “base section” refers to the lower end of the shaft, which is usually described in terms of its diameter (the base diameter).
The “top section” refers to the upper end of the shaft. If the pole is going to be extended using an arm, the shaft will be equipped with screws for mounting the arm. Otherwise, the luminaire will be mounted directly on the shaft.
The “connection cabinet” or “handhole” is an opening in the shaft about 500–1,000 mm above ground level, and enables the required electrical installations to be made. Handhole sizes vary, but they are typically about 400 mm high and 80–120 mm wide.
The shaft is attached to the ground by either inserting it into a ready-made concrete foundation or bolting it to an anchor bolt foundation. If the pole is to be installed using anchor bolts, a flange plate will be welded onto the base section during production.
Arms
A variety of arms can be used to extend the top section of the shaft, and the luminaire or luminaires will installed at the end of the arms. There are three main types of arms
The arm is attached to the top section of the shaft using screws, thereby enabling different arm solutions to be used on the same shaft in accordance with each project’s requirements.
In standard solutions, using an arm will increase the height of the light pole by 1.5 m. For example, a 10-metre light pole with an arm will consist of an 8.5-metre shaft equipped with top-section screws and a 1.5-metre arm. A 10-metre light pole without an arm will simply consist of a 10-metre shaft without any top-section screws.