Is it necessary to conduct 100% testing for explosive media?

For safety reasons, 100% testing and airtightness tests should be carried out； It is not necessary in accordance with the requirements of HG/T20583 ； After all, safety still needs to be given top priority.

There’s no need; natural gas is a fairly common explosive substance. There aren’t many that are 100% airtight. There’s no need to get nervous just because something is explosive.

1. Testing is not necessary, nor is it the only means to improve the inherent quality of welding; welding procedures, selection of welding materials, control during the welding process, and post-weld treatment are key factors in ensuring the quality of welded joints. 2. The welding process itself is guaranteed to be inherently safe; testing serves as a means to verify this process, enabling quantitative evaluation and the retention of evidence. 3. Non-destructive testing does not mean that all defects can be detected; rather, it aims to keep defects within certain limits based on specific criteria, allowing minor defects to remain. 4. Even if standards do not require 100% testing, this does not mean that control over welding quality can be reduced; end-users need to strike a balance between quality, schedule, and cost in order to manage the risks associated with equipment that handles toxic or flammable substances

From a safety perspective, it is certainly necessary; doing it is better than not doing it at all. Flaw detection involves checking the welded areas, while airtightness testing is used to check the flange connections. The standards specify certain proportions for flaw detection based on the temperature, pressure, and properties of the medium. Airtightness tests must comply with these standards, but their effectiveness can sometimes be limited, as such tests typically use air or nitrogen. Although the pressure can be maintained, the temperature cannot always be controlled. Pipelines that have undergone airtightness testing may still experience leaks during operation. In the past, steam was used for airtightness testing, and its results were better than those obtained with air or nitrogen. It may not be possible to meet the requirements regarding pressure retention time, but its effectiveness is indeed greater than that of using nitrogen or air

Firstly, it’s not necessary to follow the standard at 100%. Secondly, there is no requirement for a gas-tightness test at 150, but such a test is required according to the 6 regulations; it depends on your choice.

The standard represents the minimum requirement; raising the inspection standards will increase the cost of the equipment. Safety and manufacturing costs must be considered together. The quality of the equipment requires effective control at every stage of container manufacturing; relying on just one or two stages is not sufficient.

Upvote for #4. When this topic comes up, some people surely say things like it’s for safety reasons, but at the core, non-destructive testing has no direct relation to safety. The reason for using non-destructive testing methods is to assess the quality of weld joints; but as #4 said, non-destructive testing isn’t the only method available. The idea of relying on 100% non-destructive testing to ensure 100% reliability of welded joints is naive. This is detailed in the detection level classification; it simply limits defects of certain categories and specifications to an acceptable range, thereby keeping the risks within acceptable levels. The most effective way to improve container safety is to carry out welding work from start to finish with high quality and in accordance with standards.