Pin-type insulators are the type of insulators used for holding the HT overhead conductor on the straight running of poles. These insulators play a crucial role in the transmission and distribution of electrical power by providing insulation and mechanical support to the conductors.

Explanation:


Pin-type insulators are widely used in overhead power transmission lines due to their excellent electrical and mechanical properties. They consist of a porcelain or glass body and a metal pin or spindle that is used to attach the insulator to the pole. The conductor is then suspended from the insulator.

Key features and advantages of pin-type insulators:
- Electrical insulation: Pin-type insulators are designed to provide high electrical insulation between the conductor and the pole. This prevents leakage of current and ensures the safe transmission of electricity.
- Mechanical strength: These insulators are designed to withstand the mechanical stresses caused by the weight of the conductor and external forces such as wind and ice. They have high mechanical strength to prevent breakage or failure.
- Easy installation: Pin-type insulators are easy to install on the poles. The metal pin or spindle is securely fixed to the pole, and the conductor can be easily attached to the insulator.
- Cost-effective: Pin-type insulators are cost-effective compared to other types of insulators. They are relatively simple in design and manufacturing, making them a popular choice for overhead power lines.
- Easy maintenance: These insulators require minimal maintenance. They are resistant to environmental factors such as moisture, UV radiation, and temperature variations, which reduces the need for regular inspections and replacements.

Conclusion:
Pin-type insulators are the preferred choice for holding the HT overhead conductor on the straight running of poles due to their excellent electrical insulation and mechanical strength. They provide a reliable and cost-effective solution for the transmission and distribution of electricity.