Sound Transmitter for Ball Mill

Sound Transmitter for Ball Mill

Introduction

The Electronic Ear type PI 213 is a magnetic Sensor also known as Sound Transmitter, which is using the mill shell as a Membrane. This means the Sensor is only detecting the mill shell vibrations, caused by the Grinding balls hitting the mill lining and material in the mill, and so the Pyrotech Noise Level Sound Transmitter system is insensitive to foreign acoustic noise from other mills or surroundings.

The Pyrotech Electronic Ear is used for knowing the material level in the first chamber of ball mills and should be avoided in front of fine grinding mill chambers.

The purpose of this description is to give an example of how to adjust Pyrotech Electronic Ear equipment and how the Sensor signal has to be handled in a PLC to give an Electronic Ear Signal which can be used for indication and control purposes.

Further, it gives some examples of how the Electronic Ear signal and the Electronic Ear Supervision signals can be used to supervise the feed of a mill.

Features: -

High Accuracy for Optimization of mill
Increased Productivity
Minimum Maintenance
Increased efficiency of ball mill
Reduce wear & tear in ball
Output 4-20mA
Reduce power consumption
Improve uniformity

Application:-

Mainly used where grinding is done with the use of a Ball Mill for e.g. Cement, Power plant Mining, etc

Feedback from Customer:-

We successfully replace the Sound transmitter from the Haler unit with Pyrotech make.

Location for Micro phone unit of Ball mill Level Transmitter:-The Electronic Ear should be located in front of the first mill chamber (chamber with the Largest grinding balls) and should be mounted near the mill inlet on the downgoing side of the mill. Normally the Sensor is mounted at a distance from the mill inlet corresponding to after the 2-3 lining bolt rows (seen from the inlet) to a 1/3 length of the first mill chamber length.

The Sensor and its fixing device with rubber shock absorbers should be mounted on the top of an Electronic Ear support.

The fixing device is shown in Figure A.

Technical Specification:-

Input: Sound sensor 1mV or more.
Supply: 24V DC, 2 wire loops powered 4-20 mA.
Measuring frequency range 1-10 KHz.
Signal level from sensor 1-500 mV

Customer: - JK CEMENT, SOUTH AFRICA CEMENT PLANT, HZL, NTPC, HARYANA POWER GENERATION CORPORATION LIMITED, ThyssenKrupp, ULTRATECH CEMENT LIMITED, TATA CHEMICALS LIMITED, etc.