The installation environment and precautions for vacuum ball valves are of vital importance for the normal operation and service life of the valves. The following are the environmental factors and precautions to be considered when installing vacuum ball valves: 

I. Installation Requirements 

Temperature range 

Vacuum ball valves are typically suitable for standard environments ranging from -25℃ to +120℃. If the working medium temperature exceeds this range, high-temperature-resistant sealing elements (capable of withstanding up to +230℃) must be selected to prevent sealing failure. 

2. Pressure Range 

The valve should operate within the designed vacuum or positive pressure range. Before installation, it is necessary to confirm whether the system pressure matches the nominal pressure of the valve to prevent damage to the valve due to overpressure. 

3. Compatibility of Media 

The valve body material (such as stainless steel or aluminum alloy) and sealing material (such as rubber O-ring or metal bellows) should be selected based on the characteristics of the medium (such as corrosiveness, particle content), to ensure the sealing performance and durability. 

4. Cleanliness requirements 

The installation environment should be kept clean to prevent dust, oil stains and other impurities from entering the valve interior. The residual welding slag, iron filings and other substances in the pipeline need to be thoroughly removed to avoid damaging the sealing surface. 

5. Space Constraints 

The installation location should be reserved with sufficient space for operation and maintenance, ensuring that the valve handle and the actuating mechanism (such as pneumatic or electric devices) can rotate or operate normally. 

II. Installation Precautions 

Pipeline coaxiality and support 

Before installation, ensure that the pipeline and the valve are coaxial, and the flange surfaces are parallel. The deviation should not exceed the allowable range. 

If the pipeline cannot bear the weight of the valve, additional support structures need to be added to prevent the valve from deforming or leaking due to uneven force distribution. 

2. Sealing gasket and bolt tightening 

Select the appropriate sealing gaskets (such as rubber or metal-wrapped gaskets) according to the pipeline design requirements to ensure the sealing performance. 

The flange bolts should be tightened symmetrically, sequentially and evenly to avoid local over-tightening which may cause damage to the sealing surface. 

3. Valve Direction and Markings 

The arrow on the valve should point in the same direction as the flow of the medium to ensure that the valve operates properly. 

Before installation, it is necessary to check the valve nameplate to ensure that the model, specification and design requirements are consistent. 

4. Installation of the actuator 

Valves equipped with pneumatic or electric actuators should be installed vertically, with the inlet and outlet kept horizontal to ensure smooth operation of the actuators. 

The gas source and power supply connections should be operated in accordance with the instructions. Avoid reverse installation or incorrect wiring. 

5. Post-installation inspection 

After the installation is completed, multiple opening and closing tests need to be conducted to ensure that the valve operates flexibly and without any obstruction. 

After applying pressure, test the sealing performance of the joint surface between the valve and the pipe flange to ensure there is no leakage. 

III. Operating and Maintenance Precautions 

Slowly open and close the valve 

When operating the valve, it should be done slowly to avoid excessive force which may cause damage to the sealing surface or the actuator. 

2. Regular maintenance and servicing 

Regularly check the sealing performance of the valves and clean the impurities inside the valve chambers. 

Lubricate the moving parts such as the valve stem and the actuator to ensure smooth operation. 

3. Prevent overloading 

Avoid having the valve operate under conditions exceeding the designed pressure or temperature, to prevent seal failure or valve damage. 

4. Replace damaged parts in a timely manner 

When problems such as aging of the sealing parts and wear of the valve stem are detected, the components need to be replaced in time to prevent the failure from worsening.