INVESTIGATION OF EROSIVE WEAR IN METALLIC PIPE BENDS

Abstract

For the transportation of powders from one place to another, pneumatic Conveying is widely used in industries. Pharmaceutical Industries, chemical industries, Ash Handling work, etc., had applications of Pneumatic Conveying. During conveying, due to the bombardment of particles on the bend inner surface for changing the direction of particles, bend erosion occurs, and bend puncture is a major problem in this system. To reduce the bending erosion, researchers are working on various factors that affect the bending erosion rate, like the hardness of particles, impingement angle, bend geometry, bend material, etc, but direct bombardment of particles at 30° angle is a severe bend erosion condition. Researchers are focused on inventing a device to change the mechanism to induce swirl flow before the bend so that bombardment of particles can be reduced, leading to a reduction in erosive wear. In this research, motor-operated Swirling devices and Auto swirl devices are used to reduce erosive wear in pipe bends. CFD numerical prediction and experiments are performed to find the efficiency of the auto swirl and motor-operated swirling device. A range of 20% to 50 % reduction in erosive wear with different parameters, like the mean effective particle size and rpm of the swirling device. The motor- operated swirling device was found to be more effective than the auto swirling device. With fine powders swirling, the device was found significantly effective with a 50% reduction in erosive wear. Experiment results validate the CFD numerical prediction with 10% more erosive wear in experimentation. A significant amount of reduction in bend erosion rate is the outcome of this research, but enhancement of design and experimentation can make these devices more effective. Auto Swirl Device can be more effective with different fan blade angle and this device is very energy efficient but, in this research, found less effective due to experimentation limitations.