Flowmeters and System Solutions

Flowmeters and System solution.



Test System

About High Accuracy Flowmeter Calibration System

It is important for a flowmeter to be used continuously while maintaining its original accuracy.
OVAL designs, manufactures, and constructs flowmeter calibration facilities based on the calibration technology accumulated through the handling of industrial flowmeters and transactional flowmeters for petroleum, petrochemicals, chemical products, and natural gas.
Our flowmeter calibration facilities have been adopted in many fields, such as the verification facilities of the National Institute of Advanced Industrial Science and Technology, the verification facilities of shipping facilities of oil refining companies, and overseas calibration standard facilities.

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Verification System for Liquid (Pipe Prober)

Calibration and Test Methods

The pipe prover consists of a circular tube with a uniform inner diameter, an elastic sphere (sphere) with a specified tension against the inner wall of the tube, and two detectors. The volume inside the circular tube between the two detectors is used as the reference volume, and this value is determined by the reference unit test.
The test method consists of the pulse counter integrating the pulses transmitted from the flowmeter under test, and the detector switch signal is used as the start and stop signal for this pulse integration. A detector switch signal is used as a start/stop signal for this pulse totalization. The flow rate totalization value calculated by this method is compared with the reference volume to calculate the instrumental error.

1. Ideal as a reference unit for large and small flow rate test facilities.
2. Observation error can be eliminated in testing.
3. Observation time can be greatly shortened.
4. Ensures the safety of testing work.
5. Ideal as a reference for online testing
6. Higher accuracy than any other methods.
7. No error when starting and stopping the test.
8. Ideal as a reference unit for closed-loop testing equipment such as LPG.
9. No change in the accuracy of the reference unit due to the nature of the fluid being measured.
10. Easy to automate.

Verification Systems for Gases

Reference flowmeter system

The reference flowmeter system is a verification facility that uses a servo gas flowmeter, ultrasonic flowmeter, or turbine flowmeter as a reference

SV meter method (critical nozzle)

The SV meter is a highly accurate and reproducible flow generator that utilizes the properties of the sound velocity range (critical flow) of gas flow. It has been adopted as a national flow standard in many countries around the world.
There is no other flowmeter that can match its reproducibility. Precisely because it is a flow generator rather than a flowmeter, it does not require a flow control system, making it ideal for calibration standards.
Compared to the reference flowmeter system using a general flowmeter, which requires periodic calibration, the SV meter, which has no moving parts, is advantageous in terms of running cost as well as reliability.

OVAL is the world's specialist in national flow standard machines = SV meters (critical nozzles)

1. Supplies the world's flow standard SV meter with the latest ISO-compliant configuration at low cost.
2. Manufacture of the trinity of "SV meter alone ⇒ ISO-compliant housing with sensor ⇒ fluid calculation device
3. We are proud of our manufacturing technology for SV meters and our ability to guarantee calibration with JCSS-acquired equipment.

Recommended for the following customers

1. We want to measure with high accuracy, but the results of gas flow rate measurement differ from one flowmeter to another! Which one is the real one?
2. We are still using the "gas flowmeter + flow control system", but we want to eliminate the waviness!
3. We want to emphasize reproducibility, even if it is a single point measurement, to make a pass/fail judgment of the product based on the flow rate value!
4. We want to attach metrological traceability certification to our measurement results for external customers.
Principles and usage of critical nozzles.

National Standard Equipment

Measuring instruments such as flow meters are calibrated to the correct value using a standard instrument (working standard).
The standard is also calibrated with a more accurate standard (specified secondary standard).
In this way, the search for an accurate standard finally leads to the national standard (specified standard).
In addition to calibration facilities using working standards and specified secondary standards, Oval is also involved in the design and construction of calibration facilities for national standards in Japan and overseas.

Provided by National Institute of Advanced Industrial Science and Technology