In industrial fluid control systems,pressure valves and vacuum valves serve distinct but critical roles—yet their differences are often overlooked.This article clarifies these two core components: defining their basic functions,breaking down key distinctions in design,application,and performance,and guiding proper selection for positive-pressure or vacuum-based systems.It aims to simplify understanding for practical engineering and operational needs.
Pressure valves are core components for controlling fluid pressure in hydraulic and pneumatic systems.By adjusting the opening and closing of the valve core and its opening degree,they maintain the stability of system pressure and prevent overpressure damage.Its essence lies in adapting to different working conditions,capable of achieving functions such as pressure reduction,overflow,and sequential control.It is widely used in industrial valves,construction machinery and other fields,and is a key component for ensuring the safe and efficient operation of the system.Pressure valves include types like the pressure relief valve,which is key for overpressure protection.
Vacuum valves are special valves suitable for vacuum systems, used to control the on-off of gas media in vacVuum pipelines,regulate flow rates or maintain vacuum degrees.Its essence lies in maintaining good sealing performance in low-pressure or ultra-high vacuum environments, preventing the infiltration of external gases,and ensuring the stable operation of vacuum chambers,coating equipment and other devices.It is a core control component in the field of vacuum technology.The vacuum relief valve working principle focuses on preventing external gas infiltration to maintain system vacuum.
The core working principle of a pressure valve is to regulate the movement of the valve core by utilizing the balance relationship between fluid pressure and spring force.When the system pressure is lower than the set value,the spring force presses the valve core tightly against the valve seat,and the valve closes.When the pressure rises above the set value of the spring,the fluid pressure pushes the valve core to move,opening the valve port to discharge some of the fluid until the pressure drops back to the set range,and the valve core returns to its original position, thereby maintaining the stability of the system pressure.
The core working principle of a vacuum valve is that the driving mechanism drives the valve core to move,and in combination with the sealing structure,it realizes the on-off of the medium in the vacuum system and the control of vacuum degree.When the valve is in the closed state,the valve core is closely attached to the valve seat,preventing outside air from seeping into the system and maintaining an internal vacuum environment.When it is necessary to open or adjust,the drive mechanism moves the valve core,opening the valve port to achieve gas flow or vacuum degree adjustment,meeting the working conditions of vacuum equipment.
Additionally,the pressure vacuum valve working principle integrates both positive-pressure relief and negative-pressure protection mechanisms.
The application cases of pressure valves and vacuum valves are quite different.
Pressure valves are widely used in hydraulic/pneumatic systems,such as pressure regulation in construction machinery and overpressure protection in industrial pipelines,to ensure the stable operation of equipment under positive pressure conditions.
Vacuum valves focus on the field of vacuum technology, such as vacuum coating,semiconductor manufacturing,vacuum heat treatment and other scenarios.The core is to maintain a negative pressure environment in the system.
The core differences in design and components between pressure valves and vacuum valves lie in the sealing logic and pressure adaptation structure.
The pressure valve focuses on pressure-resistant design.Its components include a high-pressure resistant valve core and a pressure-regulating spring.It controls pressure by balancing the pressure with the spring force.
Vacuum valves emphasize high sealing performance,mostly using flexible sealing parts,without pressure regulating springs,and equipped with precise drive components to prevent external gases from seeping into the vacuum system,making them suitable for low-pressure working conditions.
Pressure valves and vacuum valves differ significantly in terms of materials and applicable pressure ranges.Pressure valves need to withstand high-pressure shock and are mostly made of high-strength materials such as cast steel and stainless steel.They are suitable for positive pressure conditions and the pressure range varies from normal pressure to tens of megapascals. Vacuum valves focus on high air tightness and corrosion resistance.They are commonly made of stainless steel or copper alloys and are equipped with fluororubber seals.They are suitable for negative pressure environments and can cover the pressure range from low vacuum to ultra-high vacuum.
There are significant differences between pressure valves and vacuum valves in terms of equipment cost and maintenance.The structure of the pressure valve is relatively simple.Its core components are the spring and the valve core.The manufacturing cost is low.Daily maintenance only requires regular checks on the elasticity of the spring and the wear of the valve core.It is easy to operate.
Vacuum valves,due to their strict requirements for sealing performance,need to be equipped with high-precision sealing parts and drive components,resulting in higher equipment costs. Maintenance requires regular testing of sealing performance to prevent air leakage,and the process is more meticulous
The pressure valve has strong automation adaptability and is often linked with the hydraulic system.It can be combined with ordinary solenoid valves and pressure sensors to achieve automatic pressure regulation.The integration difficulty is low and it is compatible with most industrial production lines.The automation requirements for vacuum valves are higher.They need to be equipped with vacuum gauges and high-precision servo drives,and must be coordinated with vacuum chambers and vacuum pumps.The airtightness and pressure fluctuations need to be taken into account,and the compatibility debugging of system integration is more complex.
The safety core of a pressure valve is to prevent overpressure.It must meet the pressure resistance and explosion-proof standards.Faults can easily cause pipeline impact or leakage, which has a relatively direct impact on the working environment.
The safety of vacuum valves focuses on preventing vacuum failure and the infiltration of external gases.Leakage can disrupt the vacuum environment but poses no risk of high-pressure shock. Some high vacuum valves need to be equipped with helium detection devices,and the materials need to have a low outgassing rate.The requirements for a clean environment are even more stringent.
The operation threshold of the pressure valve is low.Operators only need to master the basic pressure adjustment and spring calibration methods.Daily maintenance does not require special tools, and ordinary technicians can handle it after simple training.
Vacuum valves have higher skill requirements.Operators need to be familiar with the vacuum degree detection,seal replacement,and leak detection processes,and also understand the pressure balance principle of the vacuum system.They can only operate and maintain them independently after professional training.
When a positive pressure system is in operation,pressure valves are preferred.The core reason is that their design is suitable for positive pressure conditions.Through the pressure balance mechanism of the valve core and the spring,they can precisely maintain the stability of the positive pressure within the system and prevent overpressure from damaging the equipment. The pressure valve has a simple structure and low cost.It can be directly integrated with positive pressure pipelines and is easy to maintain on a daily basis.It fully meets the operational requirements of positive pressure industrial scenarios such as hydraulic and pneumatic systems.
Vacuum valves should be given priority for the control of negative pressure systems.The core reason is that they are specially designed for negative pressure conditions.They rely on high-precision sealing structures to prevent the infiltration of external air and avoid damaging the vacuum environment of the system.The vacuum valve can precisely adjust the opening degree of the valve port,achieving stable control of the vacuum degree.It is suitable for different negative pressure scenarios ranging from low vacuum to ultra-high vacuum,and is easy to maintain with strong adaptability.
When both pressure and vacuum risks exist in the system,pressure and vacuum safety valves should be selected.It integrates dual functions of positive pressure relief and negative pressure air replenishment.When the positive pressure exceeds the limit,it automatically initiates pressure relief to prevent equipment damage due to overpressure.When the negative pressure exceeds the standard,introduce normal-pressure gas from the outside to prevent the cavity from being crushed by the atmospheric pressure.Its structure is compact,suitable for complex working conditions,and it is an efficient component that takes into account bidirectional pressure protection.For example,a pressure vacuum relief valve for storage tank is widely used to protect tank structures from pressure or vacuum damage.
Zhenchao‘s pressure valves and vacuum valves stand out.One reason is that they have technical advantages.For instance,the pressure valve has a patent for anti-freezing and anti-crystallization,
and it solves the problem of low-temperature seal failure by relying on the gravity seal of antifreeze.The vacuum valve is well sealed with no leakage rate and has strong conduction capacity.Second,it has a wide range of adaptability.Vacuum valves can be used in multiple fields such as semiconductors and aerospace,while pressure valves are suitable for extremely low temperatures and other harsh working conditions.Moreover,the valve has a reliable structure, strong durability,and can replace imports,enjoying a good reputation.
Pressure valves and vacuum valves differ sharply in design,application,and operation—tailored to positive-pressure and negative-pressure scenarios respectively.Pressure vacuum relief valves fill the gap for dual-risk systems.ZhenChao’s valves stand out for technical and practical advantages. This breakdown aids proper valve selection,supporting efficient,stable operation across industrial fluid control setups.
Q1:What are the core differences in the working principles between pressure valves and vacuum valves?
A1:The core of the pressure valve regulates the valve core by the balance of fluid pressure and spring force,maintaining positive pressure stability by opening and closing the valve port.The vacuum valve relies on the driving mechanism to control the fit between the valve core and the sealing structure,isolating the external gas to achieve the on-off and negative pressure maintenance of the vacuum environment,and has no spring pressure regulating structure.
Q2:In which industry scenarios are vacuum valves more suitable?
A2:The vacuum valve is suitable for negative pressure conditions and is mainly used in the vacuum technology field,such as vacuum coating in semiconductor manufacturing,vacuum heat treatment in aerospace,and vacuum chamber experiments in scientific research,etc.Its core function is to maintain a stable negative pressure environment in the system.
Q3: What are the key points for maintaining pressure valves?
A3: Maintenance of pressure valves focuses on basic components:Regularly inspect the wear of the valve core to prevent seal failure.Test the elasticity of the pressure regulating spring to prevent the decline in pressure regulation accuracy.No special tools are needed on a daily basis. Ordinary technicians can complete routine maintenance operations after simple training.
Q4: What is the core function of a pressure vacuum safety valve?
A4: The pressure vacuum safety valve is a bidirectional protective component:when the positive pressure of the system exceeds the limit,it automatically opens to release pressure and prevent equipment damage.When the negative pressure exceeds the standard,external normal pressure gas is introduced to prevent the cavity from being crushed by the atmospheric pressure,which is suitable for complex working conditions where both positive and negative pressure risks exist simultaneously.
Q5: What are the difficulties in the automatic integration of vacuum valves?
A5: The automation integration of vacuum valves requires the matching of vacuum gauges and high-precision servo drives,and needs to be coordinated with vacuum chambers and vacuum pumps.It is necessary to focus on coordinating the issues of air tightness and pressure fluctuations.The complexity of system compatibility debugging is much higher than that of pressure valves.
