Glass tube rotameter
The glass tube rotameter is another type of rotameter that, like the metal tube rotameter, is a fluid flow measuring device that works on the principle of changing the flow surface. Rotameters are used in various industries such as chemical, petrochemical, pharmaceutical, water and sewage and other industries to measure the flow of liquids and gases.
The glass tube rotameter consists of the following main components:
1. Glass tube: This part acts as the main chamber for fluid flow. The transparency of the glass allows direct observation of the flow and position of the float. The glass tube also provides resistance to chemical corrosion in many corrosive materials.
2. Float: The float is usually made of corrosion-resistant materials, and its shape may vary depending on the type of fluid and flow conditions. This float moves inside the glass tube and its position relative to the scale engraved on the body shows the amount of current.
3. Scale: On the glass tube, a scale is engraved by which the position of the float can be read relative to the volume of fluid flow. The scale may be graduated in units such as liters per minute (L/min) or cubic meters per hour (m³/h).
4. Fluid inlet and outlet: The rotameter has connections that direct the fluid flow into and out of the device. These connections can be made of metal or other materials that are compatible with glass and fluid.
How it works
Like the metal tube rotameter, the glass tube rotameter works based on the principle of balance between gravity and fluid flow. When the fluid enters the rotameter from the bottom, the float moves downward due to gravity. As the fluid flow increases, the upward pressure caused by the flow increases and pushes the float upwards.
The equilibrium position of the float is at the point where the upward flow force and the downward gravitational force are equal. At this point, the amount of fluid flow is read through the position of the float relative to the scale on the glass body.
Advantages and disadvantages of glass tube rotameter
Advantages:
– High accuracy: The transparent body allows for accurate viewing of the float position and accurate flow reading.
-Chemical resistance: the glass tube is resistant to many corrosive substances and this feature allows the rotameter to be used in chemical environments.
– Simplicity of construction and operation: the simple structure and no need for electricity or batteries make the rotameter a reliable tool in many applications.
Disadvantages:
-Sensitivity to breaking: Glass is sensitive to physical shocks and pressures due to its fragility and may be easily damaged in harsh conditions.
Limitation in measuring high flow rates: Glass rotameters are usually suitable for low to medium flow rates, and their accuracy may decrease at high flows.
– Inability to be used in conditions of high pressure and temperature: glass is usually not resistant to very high pressure and temperature, and this problem creates a limitation for certain applications.
Applications
The glass tube rotameter is used in various applications, including:
– Control of chemical processes
– Measuring the flow of gases and liquids in laboratories
– Water flow control is used in irrigation and water purification systems.
