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Orifice flow meter

Product catalog summary

Overview: The document provides technical specifications and operational guidelines for various measurement instruments, including pressure transmitters, flow transmitters, and orifice flowmeters. It outlines the principles, applications, and maintenance procedures for these devices.

Orifice Flowmeter Principle: The orifice flowmeter operates on the principle of differential pressure measurement. As fluid flows through a throttle device, the flow velocity increases and static pressure decreases, creating a pressure difference that can be used to measure fluid flow. This method is based on the conservation of energy and continuity equations.

Key Formula: The relationship between differential pressure and flow is given by:
qm = C/(1-β⁴)^0.5 × ξ × π/4 × d² (2△Pρ₁)^0.5
qv = C/(1-β⁴)^0.5 × ξ × π/4 × d² (2△P/ρ₁)^0.5
Where qm is mass flow, qv is volume flow, C is the outflow coefficient, ξ is the inflation coefficient, d is the throttle device diameter, △P is the differential pressure, and ρ is the fluid density.

Scope of Application: The orifice flowmeter is applicable for nominal diameters between 50 mm and 1200 mm, with specific calibration required for diameters over 1200 mm. The aperture ratio β ranges from 0.20 to 0.75, and the Reynolds number varies based on β. The nominal pressure should not exceed 16 MPa, and the precision grade is 1.0.

Operation and Maintenance: Measurement errors can occur due to changes in operation conditions. Corrections can be made using specific formulas for pressure, temperature, and pipe diameter changes. Regular maintenance includes checking and clearing the throttle device and pressure system annually.

Installation Requirements: Proper installation is crucial for accurate measurements. The orifice center, flange axis, and pipeline axis must be concentric, with minimal misalignment. The direction of flow and pressure tapping positions must align with the transmitter installation status. Specific guidelines are provided for welding and pressure tapping hole alignment.

Guiding Pressure Pipe Requirements: The material and dimensions of the guiding pressure pipe depend on the flow material's nature and parameters. The inner diameter should be larger than 6 mm, and the length should preferably be within 16 meters.

Catalog excerpts

XI'AN YUNYI INSTRUMENT CO.,LTD. 1.Pressure Transmi�er 4.Dead Weight Tester 7.Temperature Transmi�er 2.Pressure Gauge 5. Level Transmi�er 8.Density Meter 3.Pressure Calibrator 6.Flow Transmi�er https://www.yunyiinstrume

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Orifice flowmeter This measurement method is based on the law of conservation of energy and mobility continuity equation. The relationship between differential pressure and flow can be determined by the following formula: Principle As fluid flow full of a pipeline flow through the throttle device in the pipeline, the flow beam will be partially contracted in the throttle device so that the flow velocity increase, static pressure decrease, and then Static pressure difference will be formed in front and back of the throttle device. The greater flow velocity of fluid is, the greater differential...

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1. Corner taps. （Figure 1） 2. Flange taps. （Figure 2） conditions change, will occur. Therefore, to allow, (flow coefficient for the constant) the measurement can be corrected with the following formula. 1. Changes of Pressure and temperature unit) Q1—reading flow (volume unit)(volume unit) R1—the designed weight of flow material R2—the actual weight flow material 2. Change of Pipe diameter 3. G2= G1α2ε2 ／α1ε1 α 1 — The original design flow coefficient α 2 — The actual design flow coefficient ε 1 — The original design inflation coefficient ε 2—The actual design inflation coefficient 4. maintenance...

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axis and gasket concentric, the misalignment should not exceed 0.002D / β. After clamping the gasket should not be into the internal pipeline. 2. Positive and negative direction of the orifice, upstream flange taps and downstream flange taps should be coincident with the direction of the dielectric flow. Position of the pressure tapping is determined by the flow characteristics and the transmitter installation status. 3. Connecting the pipeline to the throttle device, the non-orthogonality of the welding section and the pipe axis can not exceed 1 º. After the internal welding seam should be processed...

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Figure IV 8. Requirement of the guiding pressure pipe. The material of the guiding pressure pipe is determined by the nature and parameter of the flow material, inner diameter larger than 6 mm, and the length prefer to be within 16m. 9. Installation drawing of the differential signal pipeline Cleaning fluid under test for the liquid, the signal pipeline Cleaning fluid under test for the steam, the signal pipeline installation drawing installation drawing (Figure 5) Cleaning fluid under test for the gas, the signal pipeline installation drawing (Figure 6) Cleaning fluid under test for the steam,...

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Cleaning fluid under test for the liquid, the signal pipeline installation drawing Cleaning fluid under test for the gas, the signal pipeline installation drawing

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Orifice flow meter

Orifice flow meter

Catalog excerpts

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