Although swing type check valves and lift check valves both belong to the category of check valves, their structural characteristics determine significant differences in their application scenarios, which can be distinguished from four aspects: pipeline specifications, medium properties, pressure and flow rate, and installation environment.

Pipeline specifications

In terms of pipeline specifications, swing type check valves adopt a design where the disc rotates around a hinge. This design ensures good flow passage patency, with a resistance coefficient only 1/3 to 1/2 that of lift check valves. Thus, they are more suitable for large-diameter pipelines (above DN50), and their advantages are particularly prominent in industrial main pipelines with DN300 or larger, as they can reduce the energy consumption loss of the system. In contrast, the disc of lift check valves moves up and down along the axial direction, resulting in a tortuous flow passage and relatively large resistance. They are more suitable for small-diameter pipelines (below DN50) and are easier to match in small-flow systems such as precision instruments and laboratories.

Medium properties

Medium properties are a key distinguishing factor. Swing type check valves have a large contact area between the disc and the valve seat but relatively low sealing pressure. They are suitable for clean, low-viscosity media such as water, steam, and light oil products, for example, in heating circulation systems and main pipelines of petrochemical plants. However, due to the large swing gap of the disc, if the medium contains particles, fibers, or has high viscosity, it is prone to causing jamming or seal failure. Lift check valves feature precise guiding cooperation between the disc and the valve seat, ensuring tight fitting of the sealing surfaces. They are suitable for media requiring high purity and offer more stable sealing performance at low flow rates. Nevertheless, if the medium contains impurities, it is easy to block the guiding gap, so a matching filter device is required.

Adaptability to pressure and flow

There are also differences in the adaptability to pressure and flow rate. Swing type check valves open quickly at high flow rates (3-8 m/s) and produce less water hammer effect, making them suitable for dynamic working conditions such as pump outlets and long-distance transportation pipelines. However, their sealing reliability decreases at low pressures (≤0.6 MPa). Lift check valves close more promptly at low flow rates (≤2 m/s), making them suitable for static pressure systems or occasions with small pressure fluctuations. However, under high flow rates, the resistance loss is significant, which may lead to a sudden drop in system pressure.

Installation environment

Regarding the installation environment, swing type check valves can usually only be installed horizontally. For vertical pipelines, a custom spring-assisted structure is required, which increases the cost. Lift check valves, on the other hand, can be universally installed in horizontal and vertical pipelines, and are especially suitable for compact integrated systems.

Summary

In summary, swing type check valves are preferred for large-diameter, high-flow, and general-purity main pipelines, while lift check valves are more suitable for small-diameter, high-sealing, and low-flow precision systems.