Sound emission by pipelines' open sections is one of the three primary noise sources on the territories of main gas pipelines compressor stations. Sound-emitting open sections of pipelines (superchargers' process piping) are placed above ground, on the top side of compressor yards, for process reasons. As a result, the noise level reaches 90–100 dBA and more in their proximity, and up to 85–87 dBA at the compressor stations' territories, which entails adverse working conditions for maintenance staff .
Gazprom VNIIGAZ LLC has developed an algorithm for gas transportation noise protection. It involves three possible activities to reduce the noise level of pipelines' open sections : using low-noise natural gas superchargers with the simultaneous elaboration of smooth piping turns, installation of in-pipe noise killers, or soundproofing pipeline surfaces. Unfortunately, low-noise superchargers are only theoretically possible at the present level of technology, and the smooth piping turns require large areas and increase the structures' metal consumption. In-pipe noise killers are more technically feasible and very effective, though they have not been used until recently due to process issues. On the other hand, the acoustic coating of pipeline surfaces is widely used.
The article gives the results of the extensive bench and full-scale testing of different types of soundproofing structures. Different test benches were used, including those within RAACS and full-scale testing at actually operating plants. As a result, some recommendations were developed for the effective use of soundproofing structures. It is found that elastomer-based structures have a significant advantage in soundproofing pipelines.
The study shows the results of using an elastomer-based soundproofing structure at an operating compressor station. In addition to the acoustic structure on the open pipeline surface, detachably-mounted enclosures were installed for the first time on the block and control valves of superchargers' process piping. The plant noise level met the sanitary regulations after the implementation of this activity. After the necessary customization, this technique can be successfully used in other business segments of PJSC Gazprom, where there are cylindrical or flat surfaces with highly-intensive sound emission: in natural gas production, transportation, and processing.
Keywords: PROCESS PIPING, NOISE, SOUNDPROOFING, SOUND INSULATION, ACOUSTIC REDUCTION, NOISE REDUCTION, BENCH AND FULL-SCALE TESTING OF SOUND INSULATION, RECOMMENDATIONS ON USING BEST STRUCTURES.