Tower erection can be performed in several ways, depending on the type of tower being erection. Here is a quick overview of different transmission tower erection methodologies.
Build Up Method
The build-up method involves erecting towers component by component. All tower components are kept on the ground in the bottom-to-top sequence. The purpose of this step is to avoid the loss of time for searching the components. The erection procedure is executed bottom upwards.
Through this method, the tower erection team assembles large tower sections on the ground and erects those sections as units. The equipment for lifting and adjusting those sections can be a mobile crane or a gin pole.
Ground Assembly Method
The ground assembly method involves assembling the tower on the ground and erecting the whole unit. The tower is generally assembled horizontally along the direction of the transmission line. This allows for the proper alignment of the tower’s arms once it is erected.
Once the assembly is complete, the tower is picked up using a crane and affixed to its foundation. Working on this erection method, the workers choose a horizontal place close to the foundation.
The first step involved in a helicopter method is creating sections of the tower. The first or base section of the tower is affixed to the foundation. Then, the next section is bolted to the base section of the tower. Other sections are added to the tower structure in the same manner until the tower is completely erected. This method is called the helicopter method because it usually involves using a helicopter to lift and adjust the tower sections.
The foundation plays a vital role in tower stability, as it transfers the mechanical load of the transmission system to the ground. Without a proper foundation, a tower will fail to perform the job it was designed for. A foundation is designed typically depending on the type of soil of the location of the tower erection.
In some cases, when a conventional tower foundation is not an appropriate choice, pile foundations may be used. The typical application of such tower foundations can be seen on the river banks, mid-streams, or both.
Factors usually considered when preparing tower foundations are as follows.
- Type of load on the foundation
- Stability analysis of the tower foundation
- The foundation’s resistance against the uplift
- The foundation’s resistance against the down thrust
- The foundation’s resistance against the side thrust
- The foundation’s resistance against the uprooting of the stub
Stringing & Tensioning
We do the installation of insulators, stringing, tensioning, clamping, and dead-end, mid span joints and repair the jumper’s spacer, spacer damper & jumper terminals.