MEASUREMENT WHILE DRILLING SYSTEM

1.Work Environment Parameters：

Pulser: positive pulse, key type

Size of non-magnetic drill collar: 89mm ～ 229mm(3.5”～9”)

Mud displacement: 10---55L/S

Mud density:1g/cm³ ～ 2.1g/cm³(7.5ppg～18ppg)

Sand content : <2%

Working temperature of instrument under the shaft:-30℃～ +150℃

Diameter of instrument:Φ48mm andΦ38mm

Pressure resistance of instrument under the shaft: max 135MPa(20000PSI)

2.Measurement Accuracy and Range of Directional Probe:

Measurement accuracy of inclination: ±0.1° range: 0-180

Measurement accuracy of azimuth: ±1° range: 0-360

Measurement accuracy of gravity tool face: ±1° range: 0-360

Measurement accuracy of magnetic tool face: ±1° range: 0-360

3.Measurement Accuracy and Range of Gamma Probe:

Measurement range: 0-1000API

Sensitivity: 2/API

Measurement accuracy: ±2%

Resolution ratio: 173mm (6.8”) (thin well, 8”hole, 50%)

Vibration (3 axles):30g, 50-300Hz

Compact: 500g, 0.5mS axle Z

1000g, 0.5mS axle X and Y

4.Measurement Accuracy and Range of DirectionalGamma:

Measurement range: 0-1500API

Sensitivity: 0.65CPS per API

Measurement accuracy: ±2%

Resolution ratio of thin layer: 8.8” (thin well, 8”hole, 50%)

Vibration (3 axles): 20g, 50-1500Hz