VERIFICATION OF PRESSURE GAUGE (SPRING MANOMETERS)

A pressure gauge is a specialized instrument used to measure pressure differences in various environments, commonly used in laboratory settings or in industry where precise pressure measurements are required, such as in gas systems or ventilation systems. Pressure gauges play a crucial role in maintaining and monitoring the correct operating conditions in a wide range of applications.

Pressure gauges are classified as measurement devices that require mandatory verification as per the regulations issued by the Directorate for Standards, Metrology, and Quality of Vietnam. They are under the state management of the Ministry of Science and Technology.

Pressure gauge verification, specifically spring manometer verification, is a critical procedure conducted by authorized verification organizations. This process is designed to assess and ensure that these gauges comply with the requisite technical measurement requirements.

​The verification of a pressure gauge, like any precision instrument, is crucial for several reasons:

• Accuracy: To ensure that the manometer is providing accurate measurements.
• Safety:  Timely detection of damage to prevent incidents that may occur during operation. In certain applications, an incorrect reading can pose a safety risk. 
• Reliability: To help maintain the reliability of the instrument over time.
• Compliance with Legislation: Adhere strictly to legal regulations as stipulated in Circular 07/2019/TT-BKHCN

​Therefore, it’s essential to have your pressure gauge verified regularly to ensure its accuracy and reliability.

Spring pressure gauges, which encompass pressure and vacuum pressure gauges, have a measurement spectrum range from -0.1 MPa to 250 MPa, with with an accuracy from 1% to 6%.  These instruments are verified in accordance with the ĐLVN 08: 2011 - Pressure gauge with elastic sensing elements - Methods and means of verification.

Before pressure gauges are put into operation, an initial verification is mandatory. Additionally, periodic verifications are conducted as per regulations to evaluate the integrity of these instruments and to ensure they maintain their accuracy. Lastly, post-repair verifications are performed to confirm that the instruments have been properly repaired and are ready for use again. 

The verification of pressure gauge must be carried out by ĐLVN, ĐLVN 08: 2011 which encompasses the following steps:

• The pressure gauge that needs to be verified must be in normal operating condition, complete with all components and accessories, free from corrosion, cracks, or rust. The needle should not be bent or broken, and the dial, threads, connectors, and other details should be undamaged.
• The glass of the gauge should be free of cracks, bubbles, dirt, mold, or any other defects that could hinder the reading of the numbers. The glass can be made of other transparent materials, these materials must maintain their transparency under long-term working conditions
• The casing of the pressure gauge that needs to be verified and used in a pneumatic environment must have a vent to allow for easy gas escape in case the spring is damaged, this vent should be equipped with a dust shield.
• The pressure gauge should display the following information: the measurement unit, the manufacturer's name, the serial number, the measuring environment, and the accuracy class.

• The Pascal (Pa) is the officially recognized unit for pressure measurement, with other units being governed by specific legal regulations.
• The upper measurement limit of the pressure gauge needs to be verified.
• The division value (resolution) of the spring pressure gauge scale
• The scale’s numbering should correspond appropriately with the division mark
• In the non-working state, the indicator needle should either align closely with the “0” mark or deviate from the "0" mark by a value within the permissible error range.

The verification of a pressure gauge necessitates a series of measurements that adhere to specific requirements and procedures. These include:

• Determining the fundamental permissible error during the verification process.
• Assessing the variations in error during increasing and decreasing pressure.
• Evaluating the hysteresis, or lagging, error.
• Measuring the duration for which the gauge can bear a load.

Step 4: Processing the Results 

• After the verification process, pressure gauges that fulfill the requirements of the procedure are granted a verification certificate and marked with a verification stamp or sticker. 
• pressure gauges that fail to meet one of the specified requirements are not issued a certificate, and any pre-existing verification marks are removed.

​The verification cycle of pressure gauge is 12 months.

For pressure gauge verification, it's crucial to engage with authorized verification centers, as outlined in Decree 105/2016/NĐ-CP. This decree regulates the operational prerequisites for organizations involved in the verification, calibration, and testing of measuring instruments and standards. Customers have the option to either send their device to these centers or avail of onsite verification service at their location. To guarantee the best results in measurement verification, we recommend choosing esteemed organizations that boast a cadre of proficient technicians.

Dong Tam Measurement and Technical Trading Service Co., Ltd is one of the designated verification entities from the General Department of Quality Measurement, Ministry of Science and Technology in Ho Chi Minh City. We provide pressure gauge verification services, both in our advanced laboratory and on-site for our clients, offering superior support, coupled with cost-effective solutions, making us a comprehensive and efficient choice for all your verification needs.

At Dong Tam, we are dedicated to being the preferred choice for customers, offering the following advantages:

• Our laboratory, accredited under the ISO/IEC 17025:2017 standard, maintains stable temperature and humidity conditions to meet strict verification requirements.
• Our team of skilled, highly specialized, and experienced technicians is equipped to handle any unexpected issues during the verification process.
• Offer flexible verification costs suitable for all customers
• Provide fast, accurate, and effective service.
• Support delivery and pickup services for instruments upon customer request.
• Verification certificates are securely archived in our system and can be quickly retrieved via a QR code or through the Certificate Information Lookup Portal on our website.

To consult and request for quote on our pressure gauge verification services, please kindly contact us via the following information:

LABORATORY: DONG TAM MEASUREMENT AND TECHNICAL TRADING SERVICE CO., LTD

ADDRESS : No.57-59 Street 11, Binh Hung Residential Area, Binh Hung Commune, Binh Chanh District, Ho Chi Minh City

TEL: 028 375 83 869 - Hotline: 0909 347 891 (Mr. Lâm)

Email: info@dongtam-mes.vn