Wedge Flow Meter for Viscous and Abrasive Fluids

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Wedge Flow Meter DP Flow

The wedge flow meter is a new type of flow measurement device for viscous and abrasive fluids.

It features a special structure with no stagnant zones and no clogging. It is robust and has a long service life. It can be used to measure liquids, gases, and steam. It is particularly suitable for measuring the flow rate of fluids with low flow velocities (Reynolds number as low as 300), high viscosity, and containing dust or solid particles. Examples include crude oil, fuel oil, oil slurry, asphalt oil, coal tar, wastewater, iron ore slurry, carbon black solution, two-phase fluids, and fluids containing solid particles.

RFQDP Flow Meters

A wedge flow meter is a type of differential pressure flow meter that measures pipe flow by generating a differential pressure using a wedge-shaped throttling element.

The wedge flow meter is essentially a robust and durable differential pressure (DP) flow meter.

Wedge Flow Meter Working Principle

Its principle is simple:

A wedge flow meter utilizes a “V”-shaped wedge restriction element placed in the pipe section. When the fluid flows through the wedge restriction, a differential pressure is created across the restriction. For any fluid, the flow rate is proportional to the square root of the differential pressure over a wide range of flow rates. Unlike complex electronic flow meters, the wedge flow meter is based on fundamental physical principles, making it extremely reliable even in harsh industrial environments.

This operation relies on the basic principles of fluid mechanics: the continuity equation and Bernoulli’s energy equation. We use a high-precision transmitter to measure this differential pressure (DP). The square root of the resulting differential pressure is proportional to the flow rate, allowing for accurate calculation of volumetric or mass flow rate.

The key to this technology lies in the wedge-shaped element. Unlike concentric orifices such as orifice plates, we use V-shaped wedges welded to the pipe. This wedge acts as a dam, restricting fluid flow and creating the necessary pressure drop.

Why use a V-shape?

  • Non-clogging: The segmented opening allows solids and slurries to pass beneath the restriction without accumulating.
  • Durability: The wedge element is robust enough to withstand the impact of abrasive fluids that would damage other primary elements.
  • Viscosity handling: Maintains linearity even with high-viscosity fluids.

  1. The biggest advantage of wedge flow meters is their ability to handle viscous, sticky, or particle-laden fluids.
  2. Clog-resistant design: The angled shape ensures that suspended solids, sludge, or tar do not accumulate on the meter.
  3. Stable readings: Even with heavy crude oil or wastewater, the instrument maintains accuracy without frequent cleaning.
  4. Wedge flow meters are robust and durable. Their wedge structure is sturdy and lacks sharp edges that are susceptible to rapid wear. This ensures a long service life, even in highly corrosive process fluids.
  5. The wedge design of this flow meter allows it to maintain a stable flow coefficient even at Reynolds numbers as low as 500. This means accurate data can be obtained even at slow flow rates.
  6. Due to the symmetrical nature of the wedge restrictor, these flow meters offer excellent bidirectional flow measurement capabilities.
  7. Self-cleaning function prevents clogging. The unique positioning of the V-shaped throttling device allows suspended solids, fibers, and crystals to pass freely beneath the wedge restrictor. There are no “dead zones” or stagnant areas, so debris does not accumulate.

Top Features

  • The throttling element is a V-shaped wedge, which changes the throttling method. It eliminates stagnant flow zones, facilitating the smooth passage of granular fluids and suspended solids through the wedge-shaped throttling element.
  • The fluid accelerates as it approaches the wedge, and the high-speed fluid has a cleaning effect on the wedge and the inner wall of the pipe, preventing adhesion and sedimentation on the throttling element.
  • The sensor maintains a square relationship between flow rate and differential pressure even at extremely low pipe Reynolds numbers (Re=500), which is beneficial for measuring low flow rates and high-viscosity fluids. The upper limit of the Reynolds number can reach over 10⁶, thus providing a wide range of applications.
  • The symmetrical structure of the wedge sensor ensures that the same differential pressure signal is generated regardless of whether the fluid flows in the forward or reverse direction. Using two differential pressure transmitters, bidirectional flow measurement in both forward and reverse directions is possible.
  • The wedge-shaped throttling element of the wedge sensor has a rectifying and redistributing effect on the fluid, so a shorter straight pipe section can still ensure measurement accuracy.
  • The pressure loss is low, only 1/2 to 1/3 of that of an orifice plate.
  • The integrated structure design combines temperature, pressure, and differential pressure display into one unit, simultaneously displaying them on an LCD screen. This eliminates the need for pressure-sensing pipelines and the blockages and leaks caused by them, making installation convenient.
  • The wedge sensor can be configured with any transmitter specified by the user, outputting 4-20mA, differential pressure, or flow rate signals.
  • It offers high measurement accuracy (±0.5%), good repeatability (±0.1%), and a wide range (10:1).
  • Each instrument is calibrated on a standard device before leaving the factory, ensuring measurement accuracy.

Technical Parameters

Nominal Diameter (mm)DN10–DN600
AccuracyAccuracy after calibration: 1%, 0.5%; without calibration: 3%
Medium TemperatureMaximum temperature: 400℃
MaterialRectifying element material: 304, 316, 316L, HC, etc.
Body material: CS, 304, 316, 316L, HC, etc.
Nominal Pressure≤42MPa
Connection TypeFlange connection
Pressure Tap MethodThreaded pressure tapping, flanged pressure tapping
Turndown Ratio0.417361111
Applicable MediumSuitable for gases, liquids, steam, and high-viscosity media
Straight Pipe SectionUpstream 3-16DN, downstream 3DN
Flange StandardAmerican standard, German standard, Chinese standard, etc.
Special standards according to user requirements
Protection ClassSee technical parameters of the selected differential pressure transmitter
Explosion-proof RatingSee ​​technical parameters of the selected differential pressure transmitter
Ambient TemperatureSee ​​technical parameters of the selected differential pressure transmitter

Wedge Flow Meter Dimensions

Wedge Flow Meter Dimensions
Nominal diameter (mm)Installation length LFlange connection dimensions (DIN)  Unit: mm
PN1.0MPaPN1.6MPaPN4.0MPa
DNinchϕ Dϕ D0n× ϕ Aϕ Dϕ D0n× ϕ Aϕ Dϕ D0n× ϕ A
151/250095654×1495654×1495654×14
203/4500105754×14105754×14105754×14
251500115854×14115854×14115854×14
321–1/45001401004×181401004×181401004×18
401–1/25001501104×181501104×181501104×18
5025001651254×181651254×181651254×18
652–1/26001851454×181851454×181851458×18
8037002001608×182001608×182001608×18
10047002201808×182201808×182351908×22
12558002502108×182502108×182702208×26
15068002852408×222852408×223002508×26
20089003402958×2234029512×2237532012×30
25010100039535012×2240535512×2645038512×33
30012110044540012×2246041012×2651545016×33
40016120056551516×2658052516×3066058516×39
50020140067062020×2671565020×3375567020×42
60024160078072520×3084077020×3689079520×48

The above dimensions are for reference only and can be customized.

Wedge Flow Meter for Viscous and Abrasive Fluids

Wedge Flow Meter Installation

  1. The wedge-type sensor can be installed and used on horizontal or vertical pipes. When installed vertically, the fluid should flow from bottom to top.
  2. The flow direction mark on the wedge-type sensor housing should be consistent with the fluid flow direction.
  3. When flange mounting, the sealing gasket must not protrude into the flow meter pipe.
  4. The flow control valve is installed downstream of the sensor.
  5. Sensor straight pipe section length: 3-16DN upstream, 3DN downstream.
  6. When measuring fluid temperature, the temperature transmitter is installed 5D downstream of the sensor; when measuring fluid pressure, the pressure transmitter is installed 10D upstream of the sensor.
  7. Depending on the nature of the measured medium and the relative position of the wedge-type sensor and the differential pressure transmitter (or intelligent differential pressure flow totalizer), the differential pressure signal pipeline installation should comply with on-site pipeline installation process requirements.
  8. For wedge-type flow meters installed on horizontal or inclined process pipelines, the drain hole should be located directly above the pipe for liquid media, and directly below the process pipe for gases and steam.

Key Industrial Applications for Wedge Flow Meters

Our wedge flow meter is engineered specifically for the “difficult” fluids that cause standard meters to fail. We focus on harsh process flow measurement where high viscosity, low Reynolds numbers, and suspended solids are the norm.

Slurries and Sludge in Mining and Wastewater

Standard meters clog when facing fluids with suspended particles or fibers. Our slurry flow meter design utilizes a V-shaped throttle that allows solids to pass freely without accumulation. This makes it ideal for wastewater treatment plants handling raw sewage and mining operations moving ore slurries.

Heavy Oils, Asphalt, and Bitumen

For the oil and gas sector, viscous fluid flow measurement is a critical challenge. We handle fluids with viscosities up to 500 mPa.s. This includes heavy oil, tar, asphalt, and bitumen. The wedge structure maintains accuracy even when the fluid is thick and moving slowly (low Reynolds numbers).

Abrasive Chemicals and Pulp Processing

In chemical and paper industries, equipment wear is a major concern. As an abrasive media flow meter, our device withstands the erosion caused by pulp suspensions and crystallizing liquids. The robust structure ensures long-term reliability without the need for frequent maintenance or cleaning.

Dirty Gases and Solids-Laden Liquids

Whether it is coal-water slurry or dirty gases containing particulate matter, our solids-containing fluid meter delivers stable differential pressure readings. The self-cleaning nature of the wedge element prevents the “dead zones” where debris typically builds up, ensuring consistent performance in dirty gas applications.

Wedge Flow Meter installation

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Order Guide

Wedge-type flow meters are often customized based on the user’s actual measurement parameters. Therefore, you need to confirm the following parameters in advance:

  • Measured Medium: Air, Liquid, or Steam
  • Medium Temperature (°C)
  • Medium Viscosity (mPa.s)
  • Medium Pressure (MPa)
  • Unit Selection: L/h, m³/h, Nm³/h, kg/h, t/h
  • Minimum-Normal-Maximum Flow Rate Range:
  • Installation and Environmental Conditions:
  • Process Pipe Outer Diameter:
  • Process Pipe Inner Diameter:
  • Pipe Material:
  • Installation Orientation: Vertical, Horizontal, or Other
  • Connection Flange Standard:
  • Power Supply:
  • Explosion-proof Requirements: Intrinsically Safe, Flameproof
  • Explosion-proof Class:
  • Protection Class:
  • Other Requirements:

For viscous sludges, abrasive slurries, or thick oils that can clog standard flow meters, wedge flow meters are an economical and reliable option that will not be blocked by high-viscosity media.

Sino-Inst manufactures and supplies wedge flow meters, supporting customization for high temperature, high pressure, and high viscosity applications. Please feel free to contact us!

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    Wedge Flow Meter for Viscous and Abrasive Fluids - Sino-Inst

    The wedge flow meter is a new type of flow measurement device for viscous and abrasive fluids.

    Product SKU: Wedge Flow Meter for Viscous and Abrasive Fluids

    Product Brand: Sino-Inst

    Product In-Stock: PreOrder

    Editor's Rating:
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