BASICS MUD LOGGING COMPANIES

SENSORS & GAS SYSTEMS

BYAhmed Ismail Abushady

SENSORS

D E G ITA L A N A L O G

S E N S O R S C A TE G O R IE S

1- Digital Sensors

1- (Depth, ROP, Draw-Work, Block position) sensor.

2- PUMP STROKE SENSOR ….(SPM).

3- ROTATION PER MINUTE …..(RPM).

1- Digital Sensors

(Depth, ROP, Draw-Work, Block position) sensor.• Fixed on cat head of draw-work.• The draw-work sensor is intended to measure transition of a drum

reel and applicable to it transition of a traveling block

Digital Sensors

Pump stroke sensor.

• Fixed on mud pump• It start count when pump piston start moving.• Pump Rate (speed) measuring device registers

the strokes per minute of the pump.

Digital Sensors

RPM • A rotary digital electro magnetic

sensor linked to the drive unit of the rotary table or the top drive. The on-off digital signals in correspondence to the rotary speed through Data Acquisition System will be recorded to represent the Surface RPM.

2- Analog Sensors

1- HOOK LOAD …….(HKLD).2- STAND PIPE PRESSURE……..(SPP).3- CASING PRESSURE ………(CP).4- TORQUE…………(TRQ).5- Ultra sonic………(MUD LEVEL SENSOR).6- Mud Flow out.7- Mud temperature sensor.8- Conductivity.9- Mud Density.10- Gas Trap.11- TOTAL GAS SYS.12- CHROMATOGRAPH SYS.

2 -Analog sensors

HOOK LOAD.Use a pressure transducer

Normally installed on the dead line anchor system.

100 bar pressure sensor.

The sensor is supplied with a 24 VDC excitation voltage and feeds back a digital.

The out put is 4 - 20 ma

100 bar Pressure Sensor Attached with Dead Line Anchor & Protected by

PVC housing

Analog sensors

STAND PIPE PRESSURE. Installed on stand pipe.

Similar to hook load.400 bar pressure sensor.Input 24v, out put 4-20ma.

400 bar Pressure Sensor Attached with Stand Pipe

Analog sensors

CASING PRESSURE. Installed on chock manifold or kill line

depends on the rig supervisor approval.

1000 bar pressure sensor.

Input 24v, out put 4-20ma.

1000 bar Pressure Sensor Attached with

Chock Manifold

Analog sensors

TORQUE measures the rotary table current in amperes. split core transducer is clamped around the power cable that will

enable the transducer to sense the current the motor draws, which is proportionate to that required

by the rotary table.

Torque sensor clamped around motor’s power

cable

Analog sensors

Ultra sonic: The mud pit level-measuring device monitors

single pit levels. Ultrasonic transducer emits ultrasonic pulses,

which are reflected by the product surface. The level is calculated via the combined emitter and

receiver system.

Analog sensors

Mud Flow out• Sensor normally specified is

of the paddle type.• Mudflow inside the flow line

causes Deviation of the paddle and a corresponding rotation of a 1-turn potentiometer.

• Various paddle sizes are available to suit the different flow lines encountered.

Analog sensors

Mud temperature sensor• Temperature-In sensor is mounted in the

suction pit and the Temperature-Out sensor in the shaker header box.

• Either semiconductor thermistor transducers or platinum resistance elements (PRT).

• 8.5 volt excitation voltage. output between

270 and 370 micro amps.• This signal is converted by the signal

conditioner card into 0-10 VDC Analog signal for input into the computer.

Analog sensors

Conductivity

• The sensor contains two coils, known as the primary and secondary coils.

• AC current is fed to the primary coil by a Oscillator.

• The magnetic effect caused by this current is transmitted to the secondary coil by the medium surrounding the coils.

• This produces a current in the secondary coil, whose phase difference is related to the resistivity of the medium.

Analog sensors

Mud Density

• The Mud density sensor is of the differential pressure type.

• Two silicon oil filled diaphragms are placed one foot apart in the drilling mud and a highly accurate differential pressure transducer interrogates the readings and transmits a 4-20 MA signal to the computer.

• The sensors are mounted in the suction pit and in the shaker header box to provide the density In & Out measurements.

Gas System

Gas Trap

• The mud trap assembly comprises an electric motor, impeller and trap chamber.

• 110 volt power is supplied to the motor from the unit and the wattage used is monitored to indicate the status of the trap in the mud.

Gas System

FID Gas SystemPrinciple of FID operation

• Hydrogen gas is mixed with the column outlet gas at a certain ratio. The gas mixture combusts in the air atmosphere. An electrode exists at each end of the FID jet, and DC voltage is applied between the electrodes.

• If only pure carrier gas (nitrogen, helium or argon) and hydrogen gas are mixed, little current is produced between the electrodes.

• When an organic compound is mixed with the carrier gas, current is produced proportionally to the amount of organic compound present.

• This is because ions (mainly carbon ions) are generated when an organic compound combusts within the hydrogen flame, and the generated ions are captured by the collector.

• ion quantity generated is almost proportional to the number of carbons contained in the compound. However, carbon atoms in a “C=O” form do not create a signal. The presence o halogens in the compound decreases sensitivity.

• Because the ion current obtained by the FID is very low, it is amplified into a proper voltage, then output to a Chromatochart or personal computer.

HOW TO DESCRIPE

DITCH SAMPLE OR

CUTTING?