Monitoring Instruments

¦ KJ959 Coal Mine Micro-Seismic Monitoring System

KJ959 Coal Mine Micro-Seismic Monitoring System is a distributed and online micro-seismic monitoring system. According to the substations connected by network, the signal from vibration sensor can be amplified, filtered and converted in real time. Then data transfers to main station by internet. Each substation can collect up to 6 channels of vibration signals at the same time. According to the actual situation, by increasing the number of substations to achieve expansion. The distributed pattern makes the analog signal cable of the vibration sensor to the substation be the shortest, which can minimize the influence of noise, crosstalk and attenuation.

The advanced time synchronization algorithm is adopted between the substations, so that the sampling time is strictly synchronous, and the error of the travel-time record of the seismic wave is reduced to the maximum. The software on main station filters, recognizes, intercepts real time vibration waveform from substation, generates lists of micro-seismic events, manages database and push to the client. The client software gets the lists of micro-seismic events from database, calculates event’s energy, locate coordinate, and update “Location nephogram of micro-seismic events” and “Micro-seismic event report”.

¦ Instrument Composition

KJ959 Coal Mine Micro-Seismic Monitoring System is composed by KJ959-Z Micro-Seismic Main Station, KJ959-F Mine Intrinsically Safe Seismic Substation, KTG24 Ground Optical Transmitter and Receiver, KT105A-J1 Mine Intrinsically Safe Switch, KTG12(A) Mine Intrinsically Safe Optical Transmitter and Receiver, GZC10 Mine Intrinsically Safe Tri-component Vibration Sensor, GZC10 Mine Intrinsically Safe Vibration Sensor, KDW660/12B2 Mine Explosion-Proof and Intrinsically Safe DC Power Supply, KDW127/12B Mine Explosion-Proof and Intrinsically Safe DC Power Supply and Monitoring Software.

¦ Application

Rupture process, strength and range of coal seam and surrounding rock monitoring

Mine earthquake and rock burst monitoring and warning

Water inrush from roof and floor monitoring

Coal and gas outburst monitoring and warning

Coal pillar fracturing and tectonic activity zone monitoring

Tunnel surrounding rock stability and slope stability monitoring

Large underground oil and gas storage monitoring

Small coal mine cross-border mining monitoring

Hydraulic fracturing for coal seam methane effecting monitoring

Coal mine “Three Zone” development height monitoring

Development process of water flowing fractured zone at roof and floor

¦ Parameters and Specifications

? Main station

·CPU: 4-core and more; more than 4GHz

·Memory: more than 8G

·Storage: more than 1T

? KJ959-F Mine Intrinsically Safe Seismic Substation

·Channel: 6 channels

·Dynamic range : more than 130dB

·Phase equalization: less than 0.2°

·Sampling frequency: 0~1.95kHz

?KT105A-J1 Mine Intrinsically Safe Switch

·Luminous emission power: -3 dBm~-15 dBm

·Optical reception sensitivity: less than -35 dBm

·Transmission speed: 10/100Mbps

·Optical fiber interface: 6 optical fiber interfaces and 2 RJ45 interfaces

? KTG24 Ground Optical Transmitter and Receiver

·Transmission speed: 10/100Mbps

·Transmission protocol: TCP/IP

? GZC10 Mine Intrinsically Safe Tri-component Vibration Sensor,

·Three axis natural frequency: 10Hz, error: ±1Hz

·Three axis damped coefficient: 0.7, error: ±0.15

·Three axis distortion: less than 0.2%

·Three axis operating frequency range: 10Hz~1000Hz

? Transmission distance: more than 10km

? Bit error rate: less than 10-8

? Polling period: less than 30s

? Storage time: more than 1 year