Parts for piston compressors include working elements such as pistons, cylinders, suction and discharge valves, as well as drive parts like crankshaft and connecting rods, pressure control components (pressure switches, regulators, gauges) and accessories such as air filters, gaskets, V-belts, safety valves and buffer cups.
In addition, a wide range of additional parts is also available, such as thermal protection, pressure switch valves, and drain valves. They also play an important role in the construction of the compressor and its proper functioning.
Thermal Protection
Thermal protection in a piston compressor serves to protect the electric motor from overheating, preventing damage. When the motor temperature exceeds a safe level, the protection interrupts the electrical circuit, cutting off the power supply. After the motor cools down and the temperature returns to normal, the device can be restarted.
How Thermal Protection Works:
- Temperature monitoring: inside the motor, there is a component that monitors its operating temperature.
- Circuit interruption: when the temperature rises above the set threshold, this component – e.g., a special melted pellet – melts and immediately disconnects the electrical circuit.
- Preventing damage: interrupting the power supply prevents further overheating and potential damage to the motor.
- Automatic or manual resumption of operation: after the motor cools down, depending on the type of protection, it may allow for automatic reactivation of the compressor when the temperature returns to a safe level.
What Can Cause Overheating and Trigger the Protection:
- Overload: Excessive current draw by the motor.
- High ambient temperature: Too high a temperature in the room where the compressor operates.
- Failures of other components: For example, a thermostat failure that could lead to overheating.
Thanks to thermal protection, the compressor operates safely, and its motor is protected from costly damage related to overheating.
Drain Valve
The drain valve in a piston compressor is used to remove condensate and water that condenses in the tank during the air compression process. This is crucial for protecting against corrosion, overloading of dryers, and ensuring dry and clean compressed air, which prevents damage to tools and other pneumatic devices.
Functions and Importance of the Drain Valve:
- Removing condensate: during compression, warm air cools in the tank, causing moisture to condense. The drain valve allows it to be discharged from the system.
- Preventing corrosion: accumulated water can cause rust and corrosion of the tank walls, leading to damage.
- Protecting equipment: moisture in the compressed air can overload dryers and damage tools and other pneumatic devices.
- Ensuring clean air: regular removal of water guarantees that the compressed air is dry and free from contaminants, which is crucial for the proper operation of machines and tools.
How It Works:
The drain valve, often in the form of a drain or butterfly valve, is mounted at the bottom of the compressor tank. It allows for manual or automatic draining of accumulated water and other contaminants.
Pressure Switch Valve (Pressure Switch)
The pressure switch valve in a piston compressor is used for automatic control of the pressure in the tank by turning the compressor drive on and off, and to relieve the pistons during shutdown, which facilitates restarting the motor. It is a key component ensuring safe and efficient operation of the compressor.
How the Pressure Switch Valve Works:
- Pressure monitoring: the pressure switch continuously measures the pressure in the compressor tank.
- Shutting down: when the pressure in the tank reaches the set upper value, the switch interrupts the electrical circuit of the motor, stopping the compressor operation.
- Relief: simultaneously, at the moment of shutdown, a special relief valve removes the pressure of the compressed air from the compressor pistons, preventing resistance during restart.
- Starting: when the pressure in the tank drops below the set threshold, the pressure switch restarts the motor, beginning the compression cycle.
Key Functions and Benefits:
- Automation: allows for automatic pressure regulation without the need for continuous operator intervention.
- Safety: protects the compressor from damage caused by excessive pressure.
- Efficiency: turns the compressor on and off at optimal moments, contributing to energy savings.
- Ease of use: facilitates engine startup after stopping by relieving pressure from the pistons.
