Electric Ear system

----Mill sound measuring instrument

Model: SHZ-7

The Electric Ear System, an intelligent digital mill sound measuring instrument, is used for monitoring the material level in a ball mill by measuring the sound caused by the grinding ball hitting the mill lining and material in the mill. Base on the output signal from the electric ear system, the mill operator will be able to control the material level in the ball mill on a constant level.

The Electronic Ear senses the noise of the mill. This noise varies with the product and the filling level of the mill. The Ear consists of a very sensitive microphone installed at the mill inlet, at the grinding ball impact point, and as close as possible to the mill shell. The foam of the Electronic Ear must nearly touch the mill shell between two rows of bolts.

The electric ear system uses a microphone probe as an ear. The microphone ear converts the mill shell sound into an electrical signal. The output signal from microphone ear correspond to degree of the material filling degree in the ball mill and should be connected to process plant control system for further signal treatment and display and recording, e.g. to be used as supervision in connection with automatic control of the mill feed.

Advantages

l      Increase productivity

l      Reduce power consumption per ton of product

l      Reduce wear of grinding media Reduce wear of grinding media

l      Improve the uniformity of the product

l      High performance

Application Examples:

Varies kinds of Ball Mill in Cement \Metallurgical \Power \Chemistry Industry

Especially in raw mill, cement mill, coal mill and some other powder milling  system in cement industry.

Technical Data:

Measurement range:                                    0~100 dB

Detect head impedance:                             About 600 Ω

Frequency range:                                         20-20,000 Hz

Distance of Detect head and display panel:    ≤100m

Output signal (according to sound level):              4-20mA

Tolerance:                                                      ±0.1dB

Workable time:                                         Continuous, 24h per day

Environment temperature:                                       -10~+55℃

Environment humidity:                             ≤85%

Power:                                             220V AC(-10~+10%)，50Hz or 60Hz

Weight                                      about 1 Kg