GB/T 23711.8-2019 in English

In-depth interpretation of the test method for high resistance of plastic lined pressure vessels

1. Background and significance of the standard

GB/T 23711 "Test methods for plastic lined pressure vessels" is divided into 8 parts, and this part (Part 8) is specifically for high resistance test. This standard is issued by the State Administration for Market Regulation and the National Standardization Administration, and aims to ensure the insulation performance of plastic lined steel pressure vessels under extreme conditions such as high temperature and high pressure.

2. Standard scope and applicable materials

3. Test equipment and test methods

The core equipment of the high resistance test is the high insulation resistance measuring instrument (high resistance meter), whose accuracy level should not be lower than 5.0 level and meet the requirements of JJG690—2003 verification regulations. During the test, the reading accuracy of the resistance value is 0.1Ω, and the repeatability standard deviation should not exceed $1/10$ of the measured value.

4. Precautions in practical application

• Test temperature:Control at $(20\pm3)^{\circ}\mathrm{C}$ to ensure a stable test environment.
• Test medium:Use clean water as the conductive medium to avoid interference from impurities.
• Wiring method:The positive terminal clamps the metal shell of the container, and the negative terminal is placed in the internal water to ensure good contact.

5. Test result judgment and improvement measures

If the test resistance value is lower than the requirements specified in Table 1, it is necessary to check whether there is a conductive path. Common problems include:

• Plastic lining material defects (such as pinholes, bubbles)
• Leakage current at joints or welds
• Ambient humidity impact

6. Implementation suggestions and standardization improvement

To ensure the accuracy and reliability of test results, it is recommended to:

• Regularly calibrate the megger and record the calibration history.
• Establish a detailed sample file, including material type, thickness and production batch.
• Strengthen operator training to ensure familiarity with test procedures and safety measures.