What are the bearing types of wet water meters and their impact on service life

Wet-type water meters are common and important metering devices in urban water supply systems. Their metering accuracy and service life are directly related to water resource management and user water costs. Among the core components of wet water meters, bearings play a crucial role in supporting the water wheel, ensuring smooth rotation, and reducing friction. Different bearing types significantly impact the performance and lifespan of wet water meters, and selecting the appropriate bearing type is a key factor in improving meter reliability and extending service life.

Main Types of Wet Water Meter Bearings
Common bearings in wet water meters fall into two main categories: metal bearings and ceramic bearings. Metal bearings are often made of stainless steel or copper alloys, offering excellent strength and toughness, suitable for typical water quality environments. Ceramic bearings, made of alumina or silicon carbide, offer high hardness and excellent wear resistance, making them suitable for water environments containing trace amounts of particulate matter. Additionally, some wet water meters utilize self-lubricating composite bearings. These bearings contain polytetrafluoroethylene (PTFE) or other solid lubricants, enabling long-term, low-friction operation without additional lubrication.

The Impact of Bearings on Water Wheel Rotation
Bearings support the rotation of the water wheel, and their frictional resistance directly impacts the sensitivity of the water wheel and the accuracy of low-flow metering. Metal bearings are prone to wear and corrosion over time. Water containing suspended particles can exacerbate scratches on the bearing surface, leading to impeller rotation problems. Ceramic bearings, due to their high hardness and corrosion resistance, maintain low friction even in poor water quality environments, ensuring accurate impeller rotation at low flow rates. Self-lubricating composite bearings reduce maintenance requirements while maintaining impeller sensitivity, but they may experience material fatigue under high temperatures or extreme water conditions.

The Impact of Bearing Material on Service Life
The service life of wet-type water meters is closely related to the bearing material. Metal bearings have a long service life in soft water environments, but are prone to rust and wear in hard water or water containing corrosive ions, reducing the overall life of the meter. Ceramic bearings offer excellent wear resistance and strong corrosion resistance, significantly extending the service life of water meters. Self-lubricating composite bearings perform well in long-term low or intermittent flow conditions, but may experience localized wear under high or surge flow conditions. Therefore, the selection of bearing material requires a comprehensive assessment of the actual water supply environment, water quality conditions, and meter diameter.

The Impact of Bearing Accuracy on Water Meter Performance
High-precision bearings not only reduce friction loss but also stabilize the impeller's rotational speed, directly impacting the metering accuracy of wet-type water meters. Low-precision bearings may cause wobble or eccentricity, resulting in inaccurate impeller rotation at low flow rates and increased metering errors. Ceramic and high-precision metal bearings maintain stable impeller rotation, ensuring metering accuracy across the entire flow range. Furthermore, precision bearings reduce vibration and noise during high-flow operation, improving overall meter performance.

Bearing Maintenance and Life Extension
The life of wet-type water meter bearings depends not only on the material and type, but also on maintenance and water quality. Regularly checking bearing wear, removing impurities from the water, and maintaining clean pipe water can significantly extend the life of the water meter. Self-lubricating bearings reduce the need for manual maintenance, but regular inspections are still necessary in high-particulate water environments to prevent localized wear that could cause the impeller to stick. For metal bearings, anti-corrosion measures, such as coating with a rust-resistant coating or using corrosion-resistant alloys, are recommended to slow wear over long periods of use.