Can the valve be exempted from the hydrostatic test?
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Can valves be exempted from hydraulic testing? The hydraulic testing pressure for pipes at higher temperatures needs to be adjusted for temperature effects, which results in a hydraulic testing pressure that is higher than the pressure tolerance of the valve’s body. How should this situation be addressed? ! !
http://bbs.hcbbs.com/thread-1025110-1-1.html This post can be used as a reference; the original poster can also consult the relevant specifications.
Valves are pressure-bearing components in pipelines, and they must undergo hydrostatic tests and sealing tests. The high temperature of the pipeline you mentioned causes water to vaporize, which in turn increases the pressure in the pipeline; at this point, the medium becomes water vapor. Therefore, when designing or purchasing valves, the required pressure level should be increased accordingly, and materials with higher heat resistance should be chosen. It is impossible to proceed without carrying out these tests. In fact, all these need to be taken into consideration during the design process
Your pipelines require temperature correction, what about valves? Are there any design considerations, and is correction needed?
This situation should indeed exist, and the same is true for equipment as well. The measures that can be taken include raising the valve rating, conducting pressure testing with spacers, or using blind flanges
The valve itself requires separate testing; what remains is the choice of the valve’s pressure rating
Is it feasible to carry out pressure testing by adding short sections or by using blind flanges? Are there any references available to support this approach?
According to standards, the valve body and valve cover, as the pressure-bearing components of a valve, must undergo hydrostatic strength and airtightness tests. Generally, when the temperature of the medium is high, the allowable stress of the material decreases, which requires an increase in wall thickness; however, you need not worry about this, as valve manufacturers take this into account during design. Moreover, valve manufacturers usually conduct pressure testing in their factories, so on-site installation only requires a seal test. I specialize in the design of low-temperature and ultra-low-temperature valves. Hope this answer is helpful! Thank you
As part of the process, valves are supposed to undergo pressure testing