As a core equipment in industrial automation control, the performance stability of explosion-proof electric regulating valves is directly related to production safety and system efficiency.According to international standards and industry norms, its calibration needs to cover four dimensions: design and manufacturing, structural dimensions, pressure testing, and dynamic performance, forming a closed-loop quality control system.

　　1、 Design and Manufacturing Standards: Compliance Verification

The design of explosion-proof electric control valves must comply with standards such as GB12237-89 "General Valve Metal Pressure Vessels" and API 608 "Metal Ball Valves", with a focus on verifying the material's pressure resistance level, explosion-proof level (Ex d IIC T4), and sealing structure. The manufacturing process needs to pass API 598 "Valve Inspection and Testing" certification to ensure that the valve body has no casting defects. The actuator needs to pass 150V withstand voltage testing and F-level insulation testing to prevent electrical faults from causing explosion risks.

　　2、 Structural dimension specification: Interchangeability guarantee

The flange connection size must meet standards such as ANSI B16.5 and GB9112-9131 to ensure seamless integration with the pipeline system; The structural length shall comply with GB12221-89 to avoid deformation caused by insufficient installation space. The diameter and stroke of the valve stem need to match the torque output of the actuator. For example, a DN100 valve is equipped with an actuator with a torque sensor range of 0-500N · m to prevent operation jamming.

　　3、 Pressure Test Procedure: Safety Verification

1. Strength test: Apply 1.5 times the nominal pressure and hold for 5 minutes. The valve body, valve cover, and welding joints must not leak. Pig iron valves need to be lightly tapped with a copper hammer to check for cracks.

2. Sealing test: Apply pressure at 1.1 times the nominal pressure and hold for 3 minutes. The leakage rate must comply with the GB/T 4213-2008 standard. Key valves require bidirectional testing, allowing for slight leakage of low-pressure large-diameter valves.

3. Operating force test: When the closing force limit is within one person's normal physical strength, two people can cooperate when the spindle diameter is greater than 320mm to prevent violent operation from causing seal failure.

　　4、 Dynamic performance testing: accuracy and reliability

1. Basic error and backlash: According to JB/T 7387-94 standard, when the input signal is 20%, 50%, and 80%, the valve position deviation is ≤± 1.5%, and the backlash is ≤ 1%.

2. Damping characteristics: The valve stem swing should not exceed 3 "half cycles" to avoid system oscillation.

3. Long term stability: After continuous operation for 2000 hours, the leakage increment is ≤ 5%, and the temperature rise of the actuator is ≤ 65 ℃.

　　5、 Environmental adaptability: verification of abnormal conditions

The explosion-proof casing must pass the IP68 protection test and undergo a 96 hour salt spray test without corrosion; When the medium temperature is greater than 80 ℃, a high-temperature bracket should be installed to reduce the impact of heat conduction on the actuator. Electromagnetic compatibility (EMC) must comply with the IEC 61000 standard to prevent industrial interference from causing misoperation.

Through the implementation of the above regulations, the qualification rate of explosion-proof electric control valves can be increased to 99.2%, and the failure rate can be reduced to 0.3 times per thousand hours, providing reliable guarantee for high-risk industries such as petrochemicals and power. The verification report must include CMA/CNAS qualification certification to ensure data traceability.