Understanding Acoustic Emission for Different Metal Cutting Machinery and Operations

Abstract

Abstract:Machining is one of the major manufacturing techniques where the material is removed to prepare the complete or sub-part. In general, this is also referred to as subtractive manufacturing. Due to solid-to-solid contact between the cutting tool and the work-piece, the machine dynamics get influenced by various operating parameters. This generates force and vibration, and thus noise. Over time the cutting tool reaches its end-of-life which increases the force to cut, and thus produces more vibration and noise. The noise parameter was considered in this work. A 32-element spherical microphone array acoustic camera system was used to record and analyze the sound that was emitted during the machining processes. The startup, idle, and load operating characteristics for various industrial machining equipment were monitored with the acoustic beam former microphone system. The industrial applications included a bench grinder, surface grinder, vertical band saw, lathe machine, and vertical milling machine. Analysis of the acoustic noise generated from these processes could demonstrate the similarities between the cyclical patterns of resonating sound.

Identification of Noise Levels for Skill Training Activities, Equipment, Machines and Power Tools at TVET Institutes in Malaysia

“…The level of noise produced depends on the thickness and type of metal [ 63 ]. Grinding activity is also one of the activities that are often carried out in the field of metal fabrication, and it is one of the activities that known to produce high noise level [ 57 ]. During the training time, the entire workshop area is used by students (15–25 students per group) where they perform various work activities training according to their assigned group.…”

“…Next, the metal manufacturing industry is also identified to expose workers to noise hazards [ 10 , 13 , 55 ]. Activities such as metal cutting, grinding, shearing and welding are known to produce high noise levels [ 56 , 57 ]. In 2020, an occupational noise-related hearing disorder (ONRHD) report on 7941 cases was confirmed by the DOSH [ 7 ].…”

Review of the Uses of Acoustic Emissions in Monitoring Cavitation Erosion and Crack Propagation

“…AEs have been used in the study of different materials: metals [8][9][10][11][12][13], composites [14,15], additive manufactured materials [16] and human and other living being tissues [17,18]. Other applications are real-time leak detection and localisation [19,20], tool-wear monitoring and other studies on machining processes [21][22][23][24], the health monitoring of large structures [25,26], the study of cavitation and its erosion and the monitoring of fatigue crack onset and growth. The review of these last two applications constitutes the scope of this paper.…”

Analysis of Roughness, the Material Removal Rate, and the Acoustic Emission Signal Obtained in Flat Grinding Processes

“…For example, Huda [14] detected chatter in turning processes by analyzing AE. Nikhare et al [15] stated that, over time, a cutting tool reaches its end-of-life, which increases the cutting force and thus produces more vibration and noise. Nourizadeh et al [16] described that the sound generated by tool holder vibration will result in a lowfrequency sound, while the sound generated by the friction mechanism is a high-frequency signal.…”