Vibration of foundation for rotary screw compressors installed on skid mounting

Abstract

The paper is devoted to vibration of the foundations for rotary screw compressors used for gas compression for thermo power plant installed on skid mounting. To evaluate the compressor vibration according to the industry standard VDI 3836, the user should decide whether the foundation is rigid or resilient. The foundation is rigid, if the vertical natural frequency of the foundation is at least 25 % higher than the excitation frequency. The excitation frequency, compressor running speed in Hz is normally known, while the natural frequency is usually not known. Therefore the goal of the study was to find natural frequencies of the skid using analytical calculations, SolidWorks simulation and "bump testing" on site. In the results section it is shown that vibration in axial direction is usually higher for screw compressors than in radial direction, therefore the mathematical model with compressor shaking horizontally was adopted for this study. Limitations of the bump test were discovered. The examples of distinctive and indistinctive spectrum were presented. It was concluded that for the structure of screw compressor foundation the bump testing on site is rather an ineffective tool to detect natural frequencies, because there are too many frequencies appearing in the spectrum and no natural frequencies could be distinguished from the time waveform. Therefore, testing of the equipment foundation natural frequencies has to be performed in the manufacturing facility before installing the equipment and filling the frame with concrete.

Experimental and numerical vibration analysis of surface mechanical attrition treatment

“…Experimental modal analysis was performed using the Bump Test Module of the SKF Microlog analyzer. Literature research has shown that bump testing is sufficient for modal frequency detection alone (Bean et al, 2016; Cerpinska et al, 2018; Dekys, 2017; Dekys et al, 2018). Table 3 presents the vibration measurement parameters used for experimental modal analysis and frequency response analysis.…”

Analisis Getaran pada Screw Compressor Akibat Pengaruh Putaran Rotor

“…Parameter dari waktu sinyal terlah dievaluasi, parameter ini adalah perpindahan, kecepatan dan akselerasi [16]. Cerpinska, et al [17], melakukan penelitian kompresor sekrup yang digunakan untuk kompresi gas untuk thermo power plan dipasang pada skid mounting, hasilnya menunjukkan bahwa getaran dalam sumbu aksial biasanya lebih tinggi untuk kompresor sekrup daripada arah radial.…”

Using a frequency vibration approach, examine the impact of screw rotor clearance on the screw housing in an 11kW compressor

“…In actuality, a variety of mechanisms as well as potentially additional elements like vibration, errors in torque transmission, or other sporadic operational irregularities, have an impact on clearances [5] . When the vibration is too high, the compressor does not recommend excessive axial movement or a rotation speed faster than critical when there is little clearance between the rotors [6].…”