● Structural characteristics
1. Flange pressure gauge standard orifice plate:
Regardless of the diameter of the pipeline, the centers of the upstream and downstream pressure tapping holes are located one inch each from the end faces of the orifice plate, which is commonly used in refining systems.
2. Ring chamber pressure standard orifice plate:
It is widely used due to the implementation of ring chamber pressure measurement, which improves measurement accuracy and shortens the minimum length of straight pipe segments required for installation.
3. Corner joint drilling pressure standard orifice plate:
When the caliber is above DN400, this form is more commonly used. The pressure measurement methods can be individual drilling pressure measurement, circular pressure equalization ring pressure measurement, or square pressure equalization ring pressure measurement.
4. Radial distance pressure tapping pipe segment standard orifice plate:
The center of the upstream pressure tapping hole of this orifice plate is located at twice the inner diameter of the pipeline in front of the orifice plate, and the center of the downstream pressure tapping hole is located at half the inner diameter of the pipeline from the rear end face of the orifice plate, and is located on the same section. This measurement is more accurate because the maximum differential pressure is at the contraction section of the fluid, which is 1/2 the diameter of the pipe.
● Performance characteristics
1. The structure is easy to replicate, simple and sturdy.
2. Stable and reliable performance, low price, and long service life.
3. Standard orifice plates are calculated and processed according to international standards, and do not require real flow calibration.
4. Single phase flow (liquid, gas, steam) can be measured.
5. Adopting intelligent differential pressure transmitter with high accuracy and programmable range.
6. The intelligent integrated orifice flowmeter can simultaneously display cumulative flow rate, instantaneous flow rate, pressure, and temperature.
7. Equipped with a HART communication interface, it has high stability.

Nominal diameter: DN25~DN1000 (mm)
Accuracy: ± 1.5% FS
Range ratio: standard 1:3; Expansion 1:5
Work pressure: ≤ 42.0MPa
Medium temperature: -40 ℃ -450 ℃
Medium viscosity: ≤ 30CP (equivalent to heavy oil)
Beta value: 0.2-0.8
Connection methods: flange type, clamp type, welding type
Pressure collection methods: ring chamber pressure collection, flange pressure collection, corner joint drilling pressure collection, radial distance pressure collection
Installation method: horizontal or vertical
Power supply: 24V DC (requires differential pressure transmitter)
Display: 8-bit LCD displays instantaneous flow and cumulative flow (equipped with a flow integrator)
Output signal: (1) 4-20mA DC flow signal (2) HART protocol compliant output signal
Explosion proof performance: intrinsic safety type IbIICT5
Protection performance: IP65

1. Pipeline diameter, wall thickness, and material
2. Measuring medium
3. Medium temperature (℃)
4. Working pressure of medium (MPa): maximum pressure, normal pressure, minimum pressure
5. Medium working flow rate: maximum flow rate, normal flow rate, minimum flow rate
6. Medium operating viscosity (mPa. s)
7. Medium density (kg/m3)
8. Allow for pressure loss
9. On site pipeline laying situation and form of local resistance components.

Before installing the orifice plate, carefully check whether the standard orifice plate's number, tag number, and specifications match the pipeline conditions, flow range, and other parameters.
2. When setting up a new pipeline system, it is necessary to first flush and clean the lines before installing the orifice plate to prevent debris from blocking or damaging the orifice plate inside the pipeline.
3. The center of the orifice plate should be coaxial with the center of the pipeline, and the coaxiality error should not exceed ± 0.015 * (1/β) -0.015. And the plane of the throttling end should be perpendicular to the pipeline, with an error not exceeding ± 1 °.
When installing the orifice plate, the gasket must not protrude into the inner wall of the pipeline after clamping.
5. The installation of the orifice plate must be tight and no leakage is allowed. After installation, conduct a pressure test.
6. The pressure conduit should be laid vertically or obliquely, with an inclination of not less than 1:12. The inclination of fluids with higher viscosity should be increased. When the transmission distance of the differential pressure signal exceeds 3 meters, the pressure pipe should be inclined in sections and installed at the highest and lowest points respectively
Gas collector and settler.
7. If valves need to be installed before and after the orifice flowmeter, it is best to choose gate valves and fully open them during operation; The regulating valve should be located in the downstream pipeline after 5DN.
8. The pressure pipeline should be supported by sturdy brackets, and the two pressure pipelines should be as close to each other as possible and away from heat sources or vibration sources. When measuring water vapor flow, insulation materials should be used to wrap them together, and if necessary (such as temperatures below 0 ℃), heat tracing pipes should be added to prevent freezing. When measuring dirty flow rate, an isolator or settler should be attached.
When measuring liquid flow rate, the horizontal section of the pressure pipe should be in the same horizontal plane. If throttling devices are installed on vertical pipelines, a certain distance (perpendicular direction) between the short pressure pipes will affect the zero point of the differential pressure transmitter, which should be corrected through "zero point migration".
The inner diameter of the pressure pipeline is related to the length of the pipeline and the degree of contamination of the medium. Usually, pipes with an inner diameter of 8-12mm are used within 45 meters.
11. The pressure pipeline must always maintain a single-phase fluid state. When the measured fluid is a gas, the entire pressure pipeline (including the pressure chamber of the differential pressure gauge) is in the gas phase; When the measured fluid is a liquid, the entire pressure pipeline is in liquid phase and there must be no bubbles. For this reason, a drainage valve should be installed at the lowest point of the pressure pipeline or an exhaust valve should be installed at the highest point. Special attention should be paid when installing or repairing differential pressure transmitters.
When installing the orifice plate on a vertical pipeline, the position of the pressure tapping port can be arbitrarily selected on the plane of the pressure tapping device. When the orifice plate is installed horizontally or obliquely in the main pipeline, the pressure port position is shown in Figure 6.