Production Gamma Ray

DESCRIPTION

Production Gamma Ray

The CNPS PGR gamma tool measures gamma radiation from the formation surrounding the wellbore or for particular applications. The detector comprises a 4″ NaI scintillation crystal, photomultiplier and 1.6kV high voltage power supply. All models are compact, rugged and combine excellent sensitivity with high resolution for cased hole production logging applications. Tools can be combined for tracer work and, with the addition of a gamma source, used for gravel pack investigations.

 

OPERATING PRINCIPLE

Gamma rays are detected by a high temperature sodium iodide crystal and amplified using a 10 stage photo-multiplier to a measurable level. The detector is temperature compensated to minimize photomultiplier drift. Calibration is effected by a wrap-around CNPS Calibrator with a distributed thorium source of very low radioactive content. The difference between background and calibrator levels provides a ratio between tool count rate and API units. Using the calibrator also monitors tool performance.

 

APPLICATIONS

Lithology Identification Depth Correlation Identification of Radio Active Scale Tracer Monitoring Gravel Pack Monitoring (with addition of a gamma source) INTERFACING & TOOL COMBINATIONS Simultaneous Operation with other Tools 2 pin feedthrough version for use above high power pulse neutron tools (PGR022, 111/16″, UW only) Sondex Compatible and OPTIONS Ultrawire™ toolbus (UW) or Memory toolbus (Mbus) Slickline memory or surface readout mode (with suitable telemetry controller)

 

SPECIFICATION

PGR Telemetry XTU or UMT

Pressure(max) 105MPa

Temperature(max) 177°C

Threshold 20keV

Sensitivity(niminal) 1 count per API

Deadtime Negligible

Accuracy <10%, depends on statistics

Voltage(nominal) 18VDC

Current <20mA

Length 586mm

Measure Point 134mm

Diameter 43mm

Weight 4.3kg

Material Corrosion Resistance

Throughout End Thread(top/bottom) 13/16″ 12 UN2A

GO End connector(top/bottom) 4mm single banana connector.