In order to maximize the service life of valves, it is necessary to start from multiple aspects such as design selection, correct installation, standardized operation, and regular maintenance. The specific measures are as follows:

1. Reasonable selection (design phase)
Matching working conditions:

Medium characteristics: Corrosion resistant materials (such as stainless steel and ceramic lining) are selected for corrosive media; Choose alloy steel or specially coated valves for high temperature and high pressure environments.

Pressure/temperature rating: The nominal pressure (PN) and temperature range of the valve should be higher than the actual operating conditions.

Valve selection:

Cut off gate valves and ball valves; Use globe valves or control valves to regulate flow; Anti reflux check valve.

Material optimization:

Valve body/spool: 304/316 stainless steel, Monel alloy, Hastelloy alloy, etc.

Sealing materials: PTFE (corrosion-resistant), graphite (high-temperature), metal hard seal (high-pressure wear).

2. Correct installation
Pipeline cleaning: Thoroughly remove welding slag and impurities from the pipeline before installation to avoid clogging the valve core or damaging the sealing surface.

Direction and position:

Pay attention to the valve flow direction markings (such as "low inlet, high outlet" for globe valves).

Avoid reverse or lateral installation (such as check valves that require vertical installation).

Pressure control:

The pipeline support should be stable to reduce vibration or external impact on the valve.

Reserve thermal expansion compensation for high-temperature pipelines to prevent valve deformation.

3. Standardized operation
Opening and closing operations:

Manual valve: operate slowly to avoid sudden opening and closing (especially under high pressure differential conditions).

Electric/pneumatic valves: Set reasonable opening and closing speeds to prevent water hammer effects.

Avoid unconventional working conditions:

It is prohibited to use valves to regulate flow outside the design range (such as throttling with gate valves, which may cause valve seat corrosion and damage).

To prevent long-term retention of media (especially corrosive fluids), please move the valve regularly.

4. Regular maintenance
Daily inspection:

Leakage detection: Check whether the valve stem packing and flange connection point are leaking.

Abnormal noise/vibration: Abnormal sound may indicate loose or worn internal components.

Lubrication and maintenance:

Regularly add lubricating grease (such as lithium based grease) to the valve stem threads and gear transmission components.

High temperature valves should use high-temperature resistant lubricants (such as molybdenum disulfide).

Sealing maintenance:

Soft sealed valve seats (such as PTFE) should be replaced promptly after aging.

Minor scratches on the metal sealing surface can be repaired by grinding.

Cleaning and anti-corrosion:

Clean the rust on the surface of the valve and apply anti rust paint (especially important for outdoor valves).

Valves that have not been used for a long time need to be emptied of the medium and dried.

5. Special working condition handling
High temperature valve:

Pre cooling/preheating to avoid thermal shock, the valve stem is equipped with a radiator.

Low temperature valves (such as liquefied natural gas):

Choose low-temperature materials (such as austenitic stainless steel) to avoid low-temperature brittle cracking.

Particle media:

Choose wear-resistant valves (such as ceramic ball valves) or install filters.

6. Spare parts management and replacement cycle
Vulnerable parts inventory: spare parts such as sealing rings, packing, valve stem nuts, etc. are regularly replaced.

Life prediction:

Develop a replacement plan based on valve operating frequency and working conditions (such as annual calibration of safety valves).

Use intelligent valve monitoring systems (such as vibration sensors and leak detectors) to provide fault warnings.

7. Common causes and countermeasures of valve failures
failure phenomenon
Possible reasons
Solution
Valve leakage
Aging of packing and scratching of valve stem
Replace the packing and repair the surface of the valve stem
Leakage inside the valve seat
Wear of sealing surface and blockage of impurities
Grind the sealing surface and clean the valve
Valve stuck
Corrosion and crystallization of media
Regularly start the valve and use anti-corrosion materials
Valve body cracking
Material fatigue or low-temperature embrittlement
Replace with more advanced materials
8. Summary
The long lifespan of valves depends on full lifecycle management: matching operating conditions during the selection phase, avoiding stress during installation, using them in a standardized manner during operation, and promptly repairing them during maintenance. For key process valves, it is recommended to establish maintenance records and combine intelligent monitoring technology to achieve predictive maintenance and maximize service life.