scholarly journals On-Line Tool Monitoring of Tool Wear Chipping/Breakage and Temperature Using Ultrasonic Sensors

1997 ◽  
Author(s):  
N. D. Patel ◽  
P. S. Nicholson
Keyword(s):  
Control System ◽  
Process Control ◽  
Transit Time ◽  
Signal Amplitude ◽  
Process Control System ◽  
Machining Process ◽  
Tool Monitoring ◽  
Ultrasonic Process ◽  
On Line ◽  
Carbide Inserts

High frequency (50–120) MHz, ultrasonic, AIN-sensors have been successfully applied to the study of wear, chipping/breakage and temperature of triangular ceramic and carbide inserts. These sensors readily differentiate between signals from wear and chipping/breakage and, in flight-identify the damage location with simultaneous measurement of signal amplitude and transit time. The signals are unaffected by the machining process. The temperature of the chip/tool interface can be readily obtained during the cutting process by monitoring the transit time. Preliminary studies suggest these sensors also monitor the hardness of the workpiece and the chatter during the cutting. A specially-designed ultrasonic process-control system with 100 ps time resolution with data collection speed 1–10 kHz was necessary to observe the on-line data. The same system integrated with a focused transducer can be used to follow the workpiece dimension and surface finish, on-line. The ultrasonic, process control system that has been developed is robust and can be used for other NDE applications with a resolution of sub-micron thickness. It can also monitor residual stresses.

Nitrogen removal in a SBR using the OGAR process control system

2002 ◽  
Vol 46 (4-5) ◽  
pp. 125-130 ◽  
Author(s):  
Z. Tomlins ◽  
M. Thomas ◽  
J. Keller ◽  
J.-M. Audic ◽  
V. Urbain
Keyword(s):  
Control System ◽  
Process Control ◽  
Total Nitrogen ◽  
Environmental Protection Agency ◽  
Batch Reactor ◽  
Industrial Process ◽  
Ammonia Concentration ◽  
Process Control System ◽  
Treated Effluent ◽  
On Line

OGAR® is an industrial process control system that utilises on-line redox measurements to control the aeration sequence in an activated sludge process. Compared to conventional process control systems that use dissolved oxygen, OGAR® makes use of redox as a control parameter during both aerobic and anoxic conditions. This paper reports on its first application in a sequencing batch reactor. The principal aim of this project is to demonstrate the capability of OGAR® to achieve concentrations of total nitrogen in the treated effluent of less than 10 mg/L, which are typically stipulated by Queensland's Environmental Protection Agency (EPA). In this study the use of the control system resulted in the following SBR performance: consistent effluent total nitrogen less than 5.0 mg/L; ammonia concentration reduced from 31.6 mg/L to 0.32 mg/L, effluent nitrate 2.8 mg/L; DO setpoint 1.5 mg/L had 10% higher effluent total nitrogen compared to DO setpoint 4.0 mg/L and redox end-points for nitrification 400 mV, denitrification 150 mV.

Sign in / Sign up

Export Citation Format

Share Document