News Center

What kind of valves are used for media containing solid particles?

    In industrial production, the transportation and control of media containing solid particles is a major technical challenge. This type of media (such as slurry, ash, sludge, coal dust, etc.) not only has a large difference in fluidity, abrasive characteristics, but also may be accompanied by high temperature, high pressure, corrosive and other complex conditions, the valve's structural design, material selection and performance put forward very high requirements.

    一、solid particle-containing media on the core challenges of the valve

    In the selection before, need to clarify the media characteristics of the core requirements of the valve, which is the basis for subsequent selection:

    1、Abrasion resistance needs: solid particles (especially high hardness, large particle size particles) in the flow process will be on the valve internal parts (spool, seat, flow path) to produce continuous scouring and impact, resulting in surface abrasion, dimensional deformation, and ultimately triggered by the leakage or jamming.

    2、Anti-clogging ability: particles of media in the valve chamber, gap, sealing surface and other parts of the deposition, especially when the media flow rate is reduced or the valve is in a half-open state, the stagnant particles will gradually build up, and ultimately lead to difficulties in opening and closing the valve.

    3、Sealing reliability: solid particles may be embedded in the valve sealing vice (spool and seat contact surface), damaging the sealing effect. Soft sealing materials (such as rubber) is easy to be cut by sharp particles, while the hard sealing surface if there is a small gap, particles will be in the media pressure “wedge”, exacerbating wear.

    4、Adaptability: In addition to the characteristics of the particles, the temperature of the medium (such as power plant fly ash temperature of up to 200-300 ℃), pressure (such as high-pressure slurry pipeline pressure of up to 10MPa or more), corrosive (such as the chemical industry, acid-containing slurries) and other parameters that will further limit the valve's choice of materials and structural design.

    二、Suitable for solid particles containing media valve types and details

    1、Knife gate valve (slurry valve)

    Knife gate valve is the “main force” to deal with high concentration, large particles of slurry, named because the gate plate is blade-shaped, designed to solve the problem of clogging.

    2、V-Ball Valve

    V-Ball Valve is a versatile valve with both cutting and regulating functions, especially suitable for media containing fibers and small particles.

    3、Eccentric Semi-Globe Valves

    Eccentric Semi-Globe Valves are designed for high-pressure, highly abrasive particulate media, combining the flow characteristics of a ball valve with the wear resistance of a gate valve.

    4、Pipe Clamp Valves (Hose Valves)

    Pipe Clamp Valves are “soft on hard” valves that open and close by squeezing a rubber hose, completely avoiding direct contact between metal parts and particles.

    5、Abrasion Resistant Throttle Valves

    Abrasion Resistant Throttle Valves are designed for highly abrasive particulate media where flow regulation is required to maintain stable regulation in the presence of particulate impingement.

    6、Dome Valve

    Dome valve is a special valve for controlling high pressure dusty media in pneumatic conveying system, especially suitable for positive/negative pressure powder conveying scenario.

    7、Hard seal ball valve

    Hard seal ball valve is a general-purpose valve for handling medium and low pressure, small and medium-sized particles, with both cut-off and easy adjustment functions.

    三、The selection of media characteristics of parameter analysis

    1、Particle size: ≤ 1mm fine particles can choose hard seal ball valves, V-ball valves; 1-10mm particles in the selection of knife gate valve, eccentric hemispherical valve; > 10mm coarse particles must be selected knife gate valve, pipe clamp valve.

    2、Particle hardness: Mohs hardness <5 (such as coal, sludge) can choose metal valves; 5-7 (such as quartz sand, slag) need ceramic or carbide inner parts; > 7 (such as corundum, diamond chips) must be silicon carbide ceramics.

    3、The media concentration: low concentration (≤ 30%) can choose ball valves, gate valves; in the concentration (30% -60%) selection of V-ball valves, eccentric hemispherical valves; high concentration (> 60%) must be knife gate valve, pipe clamp valve.

    4、Temperature and pressure: high temperature (>200 ℃) priority metal hard seal valves (such as eccentric half-ball valves, gate valves); high pressure (>10MPa) selection of fixed ball valves, eccentric half-ball valves; low-pressure (<1.6MPa) can be selected pipe clamp valve, butterfly valve.