Short Answer:

The main parts of a Pelton wheel turbine include the nozzle, buckets, runner (wheel), casing, and brake nozzle. Each part has a special role in converting the energy of water into mechanical energy for power generation. The nozzle directs water jets, and the buckets receive the impact to spin the runner.

These parts work together to ensure efficient operation under high-head water conditions. The design is simple but highly effective, especially in hydroelectric stations where water falls from great heights with high speed and force.

Detailed Explanation:

Main parts of a Pelton wheel turbine

A Pelton wheel turbine is a widely used impulse-type hydraulic turbine, specially designed for high-head and low-flow water sources. Its simple and efficient working relies on the perfect coordination of its main components. Each part plays a specific role in capturing and converting the water’s kinetic energy into rotational energy.

1. Nozzle and Spear Mechanism

The nozzle is one of the most critical parts. It converts the pressure energy of water into high-speed kinetic energy by releasing a narrow, focused water jet. The spear or needle valve, located inside the nozzle, is used to regulate the flow rate. By adjusting the spear, the water jet’s thickness and pressure can be controlled depending on the power requirement.

2. Buckets (Blades)

Buckets are spoon-shaped curved components mounted on the runner. Each bucket is split in the middle by a ridge or splitter, which divides the water jet into two equal parts. This design helps in changing the direction of water flow smoothly, ensuring maximum momentum transfer without splashing. The force from the water turns the buckets, rotating the runner.

3. Runner (Wheel)

The runner is the rotating part of the Pelton turbine to which all the buckets are attached. When water strikes the buckets, it causes the runner to rotate. This rotational energy is then transferred to the generator via the shaft. The runner must be strong and precisely balanced to rotate smoothly at high speeds without vibration or wear.

4. Casing

The casing is the outer cover that encloses the entire turbine system. Although the casing in a Pelton turbine is not used to generate pressure (as in reaction turbines), it serves two main purposes:

• To collect the used water and guide it to the tailrace.
• To protect the system and workers from water splashing during operation.

It also ensures that environmental dust and debris do not interfere with the operation of the turbine.

5. Brake Nozzle

The brake nozzle is a small secondary nozzle installed to stop the runner quickly after shutting down the main water supply. It sprays water in the opposite direction of the runner’s rotation, helping to stop it safely and quickly to avoid damage or overspeeding.

Additional Components

• Shaft: Connects the runner to the generator.
• Bearings: Support the rotating shaft and reduce friction.
• Base frame: Supports the entire turbine assembly.

Each of these components is designed for durability, high performance, and ease of maintenance. The Pelton wheel’s design makes it suitable for installations in hilly and mountainous regions where water can be channeled from a high altitude.

Conclusion:

The main parts of a Pelton wheel turbine—nozzle, spear mechanism, buckets, runner, casing, and brake nozzle—work together to efficiently convert high-velocity water into mechanical energy. Each component is essential for the smooth and safe functioning of the turbine, especially in high-head hydroelectric systems where reliable and efficient energy generation is required.