Advantages and maintenance guide of three-way ball valve

1、 Core advantages

1. Multi channel flexible switching

L-shaped channel: realizing two in and one out (such as A → B or A → C), suitable for medium distribution or switching scenarios, such as raw material switching in chemical pipelines.

T-shaped channel: supports three-way flow, can complete medium mixing (such as A+B → C), diversion or full on/off, commonly used in systems that require dynamic adjustment, such as cold and hot water mixing in HVAC systems.

Advantages: Single valve replaces multi valve combinations, reduces the number of pipeline fittings, saves space, and simplifies operations.

2. Efficient sealing performance

Material: Made of PTFE, PPL or metal hard seal, suitable for high temperature (-196 ° C to 450 ° C), high pressure (up to Class 1500) and corrosive media (such as acid and alkali).

Design: Bidirectional sealing structure, capable of withstanding pressure in both forward and reverse directions, preventing medium backflow and ensuring system safety.

Case: In LNG storage and transportation, metal hard sealed three-way ball valves can withstand low temperatures of -196 ℃ to avoid material embrittlement.

3. Convenient operation and long lifespan

Quick opening and closing: Switching the flow direction can be completed by rotating 90 degrees, with a fast response time (1-5 seconds), suitable for frequent operation scenarios.

Drive mode: Supports multiple drives such as manual, pneumatic, and electric, making it easy to integrate automation.

Easy maintenance: simply replace the seals to extend the service life, and the modular design supports quick disassembly and assembly.

4. Compact structure and space optimization

Integrated cast valve body: reduces leakage points, compact design saves installation space, especially suitable for pipe galleries and equipment intensive areas (such as ship engine rooms).

Comparative advantage: Compared to the combination of "two two-way valves+pipe elbows", three-way ball valves can reduce installation space by more than 50% and lower construction costs.

5. Strong adaptability to working conditions

Material selection: Based on the characteristics of the medium, cast iron, stainless steel, alloy materials, or fluorine and rubber lining structures are selected to adapt to various working conditions such as water, oil, gas, corrosive media, etc.

Extreme environment: Through structural optimization (such as metal hard seals and high-temperature alloy materials), it can meet extreme environments such as high temperature (≥ 600 ℃), high pressure (≥ 10MPa), and low temperature (≤ -196 ℃).

2、 Maintenance points

1. Regular inspection and cleaning

Appearance inspection: Check whether the valve body, flange connection, and electric actuator (if it is an electric valve) are damaged, leaking oil, or corroded, especially paying attention to the weak parts of the welds and castings.

Internal cleaning: Use a mild cleaner and a soft cloth or brush to clean the inside of the valve body and around the ball core, avoiding damage to the valve surface by acidic or alkaline substances.

Case: In the black liquor treatment system of the paper industry, it is necessary to regularly remove the scale on the surface of the valve body to prevent accelerated corrosion.

2. Sealing performance maintenance

Sealing surface inspection: Regularly check the wear of the valve seat sealing surface, and polish minor scratches with alumina grinding paste (particle size W20).

Sealing ring replacement: If the sealing ring is found to be damaged or aged, it should be replaced immediately and original accessories that meet the requirements should be used.

Testing method: After closing the valve, test the internal leakage by pressure attenuation method. If it exceeds the standard, it needs to be disassembled and inspected.

3. Lubrication and rust prevention

Lubrication parts: Apply an appropriate amount of lubricant (such as molybdenum disulfide grease) to the valve stem threads, operating rod, and bearing components to reduce wear and prevent rust.

Rust prevention measures: When not in use for a long time, apply rust proof oil or perform acid pickling and passivation treatment to enhance the resistance to chloride ion corrosion (such as in seawater desalination projects).

4. Maintenance of electric actuator

Electrical inspection: Use a megohmmeter to test the insulation resistance of the motor (≥ 1M Ω), check the tightness of the wiring terminals, and polish the oxidized contact points.

Lubrication oil change: The gearbox should change the lubricating oil every 3 months, and the oil level should be maintained at 1/2-2/3 of the viewing window.

Functional testing: Simulate power failure and test the reliability of the manual operating mechanism. The turning torque of the handwheel should be ≤ 300N · m.

5. Monitoring of operating conditions

Pressure and temperature: Avoid damage to valves caused by excessive pressure and temperature, and take insulation measures to prevent freezing in cold environments.

Media cleanliness: prevent solid particles and debris from entering the valve, avoid blockage and damage to the sealing surface.

Case: In a blast furnace gas pipeline at a steel plant, a position sensor malfunction caused a deviation of 30% between the actual valve opening and the displayed value, resulting in system pressure fluctuations.

3、 Typical application scenarios

Petrochemicals and Energy: Switching the flow direction of media in oil and gas pipelines, such as crude oil distribution and LNG storage and transportation.

Pharmaceutical and Food: Sanitary grade three-way valves (316L material, mirror polished) are used in CIP/SIP cleaning systems to ensure aseptic processes.

HVAC: Balancing branch flow in hot and cold water systems, such as underfloor heating water dividers.

Water treatment: Switching the water flow direction in the backwash filtration system to achieve automatic cleaning of the filter material.