Gas Meter Movement Sealing Inspection Device

Technical Solution

   

Technical Specifications

   

The gas meter movement sealing inspection apparatus is a dynamic sealing test device for gas meter movements, designed in accordance with the production process characteristics and testing requirements of diaphragm-type gas meter movements. It incorporates a complete set of imported pneumatic components and precision differential pressure sensors, making it the ideal equipment for sealing inspection of movements on domestic diaphragm gas meter production lines.

First：Technical Specifications for Equipment

(1) The equipment shall satisfy sealing inspections for 1.6/2.5/4 gas meter movements, featuring six independent inspection stations. Each station shall operate autonomously and automatically reset upon completion, with individual display units for inspection results;

(2) Differential pressure sensor specifications: Range: 0-1000 Pa; Resolution: 1 Pa;

(3) Accuracy class of differential pressure sensor range：0.5%;

(4) Vacuum setting range: -600 Pa to 0 (relative to atmospheric pressure);

(5) Equipment test duration setting range:0–999 seconds;

(6) Equipment pass threshold setting range: 0–300 Pa;

(7) Rotation angle of stepper motor used: 0–360°;

(8) Power supply: AC 220±20V, 50Hz;

   

Second、Product Features

1.This apparatus comprises six independent dual-chamber automated testing units, enabling simultaneous sealing inspections on four gas meter mechanisms for high production efficiency.

2.Employing single-chip microcomputers, high-precision A/D conversion, and precision differential pressure sensors, each meter position dynamically displays real-time vacuum performance of the tested chamber. Operation is user-friendly, delivering intuitive and accurate results.

3.The vacuum level required to be achieved and maintained within the tested chamber can be set via the adjustment knob on the vacuum generator assembly and the precision pressure-reducing valve. Test duration and result threshold values can be configured and stored via the control panel, with power-off retention capability.

4. The dual-chamber inspection for a single meter's movement seal integrity is completed in three stages. The rotation of the gas meter valve cover between consecutive tests is driven by a stepper motor. The entire inspection process is automatically controlled by the microcontroller. Upon completion of each test, corresponding indicator lights illuminate to denote whether the tested chamber is compliant, facilitating adjustments.

   

Third、Key Technical Specifications

1.Differential pressure sensor range: 0-1000 Pa  Resolution: 1 Pa

2. Vacuum setting range: -600 Pa to 0 (relative to atmospheric pressure)

3. Test duration setting range: 0-999 seconds

4. Stepper motor rotation angle: 0-360°

   

Fourth、Composition and Working Principle of the Device

This apparatus primarily comprises a compressed air source, control air circuit, test air circuit, a microcomputer master-slave system for operational control and detection, precision differential pressure sensors, and a workbench.

The test air circuit configuration is illustrated below：

  

 

Figure 1: (Partial) Test Gas Circuit

Employing the principle of negative pressure, the vacuum generator creates a specific negative pressure within the tested meter chamber relative to atmospheric pressure. A differential pressure transmitter then samples and displays in real-time the pressure differential between the tested meter end and atmospheric pressure. This value is monitored to determine whether it remains stable within the permissible leakage range throughout the test duration, thereby assessing the sealing performance of the tested meter movement (including valve seat, rotary valve, diaphragm, etc.). The operational control system allows direct panel configuration of test parameters (e.g., evacuation duration, pressure levels, detection time, pass thresholds) which are stored within the microcomputer host system. Once the meter is positioned, pressing the test button initiates the procedure: a cylinder lowers to seal the meter port, and testing commences according to the preset parameters. During testing, the microcontroller controls solenoid valves and vacuum generators according to different test phases. A stepper motor drives the valve cover to measure two adjacent chambers in three stages. Differential pressure sensors continuously monitor chamber pressures. Within the set test duration, measured pressure variations are compared against preset parameters to generate test conclusions, indicated by green (pass) or red (fail) signal lights. The fixture must be compatible with the sample gauge provided by the client, with pneumatic loading and unloading mechanisms employed.

   

Sixth、This apparatus is supplied with an instruction manual. This apparatus is classified as production testing equipment and not a standard metrological device. No verification certificates issued by national statutory metrology institutions are provided for any of the standard instruments.。