Väravakraanad

Väravakraanad are a type of gate valve used in plumbing and industrial applications. They are characterized by a flat, sliding gate that is raised or lowered to control the flow of fluid. When the gate is fully raised, the valve is open, allowing unrestricted flow. When the gate is fully lowered, the valve is closed, preventing any flow.

The mechanism for operating a väravakraana typically involves a handwheel that is turned to move a stem connected to the gate. This stem passes through a threaded opening in the valve body, and as the handwheel is rotated, the stem either rises or falls, taking the gate with it. The design allows for a simple and reliable method of isolating sections of pipe or controlling the passage of fluids.

Väravakraanad are commonly made from cast iron, brass, or stainless steel, depending on the application and the type of fluid being handled. They are often used in applications where a tight seal is required when closed and minimal pressure drop is desired when fully open. Their straightforward design makes them relatively inexpensive to manufacture and maintain. However, they are not ideal for throttling or regulating flow, as the partially open gate can be prone to vibration and wear. For applications requiring precise flow control, other valve types are generally preferred.