The difference and connection between hydraulic lift valve and globe valve

A、 The main difference between hydraulic lift valve and hydraulic globe valve

1. Structural differences Globe valve: The valve core (or disc) moves linearly along the centerline of the valve seat, and the opening is adjusted through a threaded rod, such as the J41H flange globe valve. Lift valve: The valve disc moves vertically up and down in the direction of the fluid, with a typical structure such as a lift check valve. There are usually guide grooves inside the valve body to ensure precise positioning of the valve disc.

2. Comparison of the working principles of two types of valves -The globe valve slowly pushes the valve core through a handwheel or actuator, and the flow rate can be precisely controlled (with an opening adjustment error of ± 5%), but when fully opened, the flow resistance is relatively high (pressure loss coefficient ξ ≈ 5-15). -The lift valve relies on fluid pressure or external mechanical force to drive the valve disc action, with fast opening and closing speed (up to 0.5 seconds), but low adjustment accuracy.

3. Performance parameters Parameter lifting valve and shut-off valve Applicable pressure PN16-PN420 (high voltage) PN10-PN160 (medium high voltage) temperature range -29℃~550℃ -40℃~600℃ Sealing grade ANSI Class IV ANSI Class VI

B、 The connection and collaborative application of the two

1. Common design -Both use metal hard seal or soft seal structures (such as PTFE), and the valve body material can be selected from WCB, 304SS, etc. According to API 598 standard, both must pass the same airtightness test (leakage rate ≤ 0.1%).

2. Functional complementarity -Lift valves are commonly used for emergency shut-off (such as in chemical plant safety systems), while globe valves are more suitable for long-term throttling (such as in steam pipelines). In the field of nuclear power, the two are often used in combination: the lifting valve quickly isolates leaks, and the shut-off valve finely adjusts the coolant flow rate.

3. Selection suggestions -Priority should be given to using lift valves in high vibration environments (such as ships); -Use globe valves for operating conditions that require frequent adjustment, such as heating systems; -It is recommended to use fluorine lined globe valves or titanium alloy lift valves for corrosive media.

The above:The principle and application of hydraulic proportional valve