EVA UPVC single union ball check valve is a type of valve used to prevent backflow in piping systems. It features a single union connection for easy installation and maintenance, and utilizes a ball mechanism to allow flow in one direction while preventing reverse flow. These valves are commonly made from UPVC (unplasticized polyvinyl chloride), making them suitable for various applications, including water and chemical handling. 

Key Features and Functionality:

• Single Union:

The "single union" aspect refers to the presence of a union fitting on only one end of the valve, allowing for easy connection and disconnection of the valve from the pipe. 

• Ball Check Mechanism:

The valve uses a ball that moves within the valve body to either allow or block flow. When flow is in the desired direction, the ball is pushed away from the seat, allowing fluid to pass. When flow reverses, the ball is forced against the seat, creating a seal and preventing backflow. 

• UPVC Material:

UPVC is a durable and corrosion-resistant plastic, making it suitable for a wide range of applications, including those involving water, chemicals, and other fluids. 

•  Vertical and Horizontal Installation: 

Can be installed in either vertical or horizontal positions. 

•  Applications:

These valves are commonly used in water treatment, pool filtration, chemical dosing, and aquaculture, as well as in general industrial and commercial settings to prevent backflow. 

Installation and Usage:

• The single union end is designed for easy installation, often with socket or threaded connections. 
• The direction of flow is typically indicated on the valve body, with the union end often being the inlet side. 
• A single union ball check valve is designed for installation in a vertical orientation.