Обзор нештатной работы регулятора давления газа РДСК-50М2 при запуске котла Buderus

Why does gas pressure fluctuate? Analysis of severe resonance in the RDSK-50M2 regulator (from 0 to 25 kPa) This video clearly captures a classic case of hydrodynamic and thermoacoustic resonance (self-oscillation) in the RDSK-50M2 direct-acting gas regulator. The footage shows how, with a gradual increase in flow rate (with only one boiler operating, flow rate ~133 m³/h), the pressure gauge needle begins to pulsate wildly, jumping from zero to a maximum of 25 kPa. Many people mistakenly blame this on the regulator itself or faulty equipment. However, a detailed engineering analysis reveals that the regulator is completely functional, and that it is the incorrectly installed impulse line that is driving it crazy. 🔍 What exactly is happening in the video (Physics of the process): The RDSK regulator is controlled solely by a balance of forces: the spring exerts pressure to open, and the gas from the impulse tube exerts pressure to close. In this case, due to installation errors, the regulator's "brain" receives a distorted signal with a critical delay: Bottleneck effect: The inlet fitting to the regulator is narrowed to 4.64 mm, followed by a copper section of DN 5 mm (40 cm long). The gas physically does not have time to flow quickly through this capillary under the membrane. This results in a phase delay of a fraction of a second in the control signal. Acoustic mirrors: The impulse line has a total length of 1.7 meters, is made of DN 15 steel pipe, and bends twice at a 90° angle. Any micro-oscillations from the boiler burner strike these corners, are reflected, and create a "standing wave" that oscillates the membrane. Parasitic volumes: Third-party branches on the DN 15 line act as mini-receivers, accumulating pressure and releasing it back out of phase, turning the signal into a "vinaigrette." Thermoacoustic effect: 1 meter of the line is in the PGB (one temperature), and 70 cm is outside in direct sunlight. The difference in temperature and gas density in the enclosed space creates spontaneous thermal pulsations in the gas mass. As a result, the automation system loses its ability to smoothly micro-regulate and switches to a rigid relay mode: "fully open / fully closed." 🛠️ How to fix this (Technical solution): To ensure stable operation of the regulator and a consistent 25 kPa pressure without any dips or surges, the impulse line must be redesigned according to the following rules: Eliminate any constrictions: Use a tube of exactly the same internal diameter along its entire length—at least 10–12 mm (including the inlet fitting to the regulator!). Straighten the line: Run the impulse line directly from the DN 100 pipe to the GRP/PGB, avoiding sharp 90-degree turns (make smooth bends). Remove unnecessary components: Completely eliminate any external branches, tees, and elbows. The line must be monolithic. Insulation: The outdoor section of the impulse line must be properly insulated with foam rubber to prevent the effects of solar heating. We do not claim to have the definitive authority on this matter. We are expressing our opinion. In this situation, additional influencing factors may overlap. Precise calculations and research are necessary to determine the full picture. #RDSK-50setup #RDSK50M #RDSK50BM #setup #pumping #self-oscillations #regulator #workingvalve #spare parts #repair kit More information about the RDSK-50M gas pressure regulator here 🌐 https://saratovgaz.ru/regulyator-davl... Repair kits and spare parts for RDSK-50 regulators here 🌐 https://saratovgaz.ru/remkomplekt-dly... Our phones: ☎️ +7(8452) 599-283, 599-719 Email: ✉️ [email protected]