Phenomenon: The shallow test of the instrument is normal. After working for a period of time in the well, the signal is getting weaker.
Reason: 1: The sensor is blocked.
2: Mud displacement exceeds the normal range of variation.
3: The viscosity of the mud becomes larger or the specific gravity becomes smaller.
4: The pump pressure is reduced.
5: The rotor eccentric wear speed is reduced.
6: The pulser telescopic sleeve becomes larger due to the high temperature.
7: The outer diameter of the mushroom head becomes smaller or the inner diameter of the restrictor ring becomes larger.
8: Fall into foreign bodies.
9: The filter block pump pressure rises.
10: The temperature at the bottom of the well exceeds the standard, causing the probe or pulse generator to not work properly.
Solution: 1: Replace the pressure sensor.
2: Adjust the displacement.
3: Treat the mud and reduce the viscosity.
4: Large-scale activity drilling tools.
5: Replace the downhole equipment.
6: Repair the mud pump.
7: Replace the probe if the bottom hole temperature is too high.
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