Advantages and Disadvantages of Series 58 Axial Flow Check Valve
Axial flow check valve is a valve that automatically opens and closes by the fluid's own pressure. Its valve disc moves along the axis of the pipeline, and the structural design focuses on reducing fluid resistance. The following is an analysis of its advantages and disadvantages and applicable scenarios:
I. Advantages
1. **Low flow resistance and high pressure drop control**
- The flow channel design is consistent with the pipeline axis, reducing turbulence and local resistance, and the pressure drop is significantly lower than that of swing or lift check valves. It is suitable for high flow and high pressure systems (such as oil pipelines).
2. **Quick response and smooth closing**
- The valve disc lightweight design combined with spring assistance has a fast closing speed and small impact, which effectively reduces the water hammer effect and protects pumps and pipeline equipment.
3. **Excellent sealing performance**
- Metal hard seals or elastic soft seals (such as PTFE) are used to maintain reliable sealing in high pressure, high temperature or corrosive media, reducing the risk of leakage.
4. **Long life and low maintenance**
- Compact structure, few moving parts, and low wear; some models support online maintenance, and seals can be replaced without disassembling the valve, reducing downtime costs.
5. **Adaptable to complex working conditions**
- Customizable materials (such as duplex stainless steel, Hastelloy) and sealing forms, suitable for extreme temperatures (-196℃ to +500℃), high pressure (Class 1500) or particle-containing media (with guide cover).
2. Disadvantages
1. **Higher cost**
- Precision machining and spring/buffer mechanism increase manufacturing costs, initial investment may be 2-3 times that of swing type, and economic efficiency needs to be combined with long-term operation and maintenance evaluation.
2. **Installation restrictions**
- Strict directional requirements (valve body arrow must be consistent with flow direction), increased installation difficulty in narrow space or complex pipelines, and customized flange angles may be required.
3. **Limited performance in low-pressure conditions**
- Relying on medium pressure to push the valve disc, closing delays or poor sealing may occur when low pressure or insufficient flow rate occurs, and a strong spring model needs to be selected.
4. **Maintenance complexity**
- Although the one-piece valve body design enhances the structural strength, it needs to be disassembled as a whole for maintenance, which takes longer maintenance time than the split check valve.
5. **Not suitable for small-diameter pipelines**
- The advantages are mainly reflected in pipelines above DN50. Due to structural limitations, the cost-effectiveness of small-diameter (such as DN15) is not as good as that of traditional lift check valves.
III. Typical application scenarios
- **Long-distance oil and gas pipelines**: Reduce pumping energy consumption under high pressure and large flow conditions, such as the outlet of the natural gas trunk line pump station.
- **Chemical plant**: Corrosion-resistant design adapts to acid and alkali media, such as the inlet and outlet of the reactor.
- **Power station system**: Anti-backflow of high-temperature and high-pressure steam pipelines, such as the turbine bypass system.
- **Offshore platform**: Compact structure saves space and adapts to salt spray environment.
- **Water treatment project**: Low water hammer characteristics protect large water pumps, such as municipal water supply booster stations.
4. Selection Recommendations
- **Preferred**: systems with high pressure (≥PN40), large flow (flow velocity > 3m/s), frequent start and stop, or sensitive to water hammer.
- **Use with caution**: For projects with low pressure, small diameter, intermittent low flow velocity, or limited budget, consider using swing or wafer check valves instead.
By weighing the working conditions and cost-effectiveness, axial flow check valves are often used as high-performance solutions in key process industries, but their applicability needs to be comprehensively evaluated in combination with specific parameters.
