Slurry cavitation diagnosis – Noise Law
Slurry pump cavitation diagnostic methods generally unable to take advantage of user traffic is constant head fall to determine whether the occurrence of cavitation method . Whether in-service pump cavitation , cavitation damage in addition to the post- observation method , you can also use ultrasonic method , the pump noise in vitro method, vibration and other methods judgments.
1 Observation method This method is, in hindsight , according to the destruction of the surface shape to be judged. Since cavitation, casting porosity, erosion wear, corrosion etc. will cause the metal surface shape different from the ideal shape . Cavitation damage of the metal surface is usually show a honeycomb , which is struck by the local speed of water leaving the metal surface of metal fatigue , so that the honeycomb is generally communicate with the outside , most of the metal perpendicular to the surface pits . Casting defects are often loose deep inside the metal , and sometimes the water erosion of the metal inside the loose , showed the surface pores and mistaken foot cavitation, but continues to remove by mechanical methods will find its inside surface there are pores.
2 Erosion wear marks are often the same trench with the flow direction , but pay attention to whether there is water vortex . This method is relatively simple and can not in contact with the pump . However, due to the noise law by week Quarters greater impact of environmental noise , when the show its highest intensity . General pump cavitation has reached a very strong phase, where the ear has been through intense cavitation cavitation popping sound judgment conditions. Therefore, the pump noise method is not suitable for on-site monitoring of the occurrence of cavitation .
3 By vibration method accelerometer vibration frequency pump probe method , the method is simple, but low sensitivity . Especially for large pumps that stiffness . Locally within the pump cavitation bubbles debacle caused by the excitation arising unresponsive , while the larger pump vibration source . Since the vibration caused by cavitation is often masked among other vibrations . Therefore, the vibration method is only suitable for on-site monitoring cavitation adjunct.
4 Ultrasonic cavitation ultrasonic measurement method is simple , and not subject to other environmental noise interference, cavitation occurrence and development of strong sensitivity . Therefore, as a pumping station at the site monitoring cavitation an ideal approach.
Post time: Jul-13-2021