Swing check valves and lift check valves

Lift-type valves are generally of small diameter, while those with larger diameters are usually swing-type check valves. In general, lift-type check valves are best installed in horizontal pipes; however, it is said that vertical lift-type check valves now exist as well, though I have not used them. Swing-type check valves can be installed either vertically or horizontally, but when installed in vertical pipes, the flow of the medium should generally be from bottom to top.

Installation requirements for check valves: Classified by structure, check valves can be divided into lift-type check valves, swing-type check valves, and butterfly check valves. Lift-type check valves can be divided into vertical and straight-through types... 1. Lift-type valves offer better sealing performance than swing-type valves, but they generate greater fluid resistance; horizontal versions are suitable for use in horizontal pipelines, while vertical versions are suitable for use in vertical pipelines ； 2. The installation location of the swing check valve is not restricted; it can be installed on horizontal, vertical, or inclined pipelines. When installed on a vertical pipeline, the flow direction of the medium must be from bottom to top ； 3. Swing check valves are not suitable for use in small-diameter valves; they can operate at very high pressures, with a PN rating of up to 42 MPa. Moreover, their diameter can also be quite large, reaching over 2000 mm. Depending on the material of the housing and seals, it can be used with any working medium and in any operating temperature range. The media include water, steam, gases, corrosive substances, oils, pharmaceuticals, etc. The operating temperature range of the medium is between -196 and 800°C ； ……

Typically, design institutes* habitually design valves with a diameter of DN50 or less (excluding DN50) as lift-type check valves, while those with a diameter of DN50 or more are designed as swing-type check valves.