This tool sub of the 4000 Stack Tools Series records the
neutron porosity of the formation. The tool also records
short and long neutron counts. It requires the use of the
4000 Stack Gamma Ray Tool Sub, which provides the
needed telemetry, and is compatible with the 4239 Stack
Density Tool Sub.
FEATURES
Properties Measured
1. Neutron Detector, Far Spacing:
He3 5.1 x 25.4 cm (2 x 10 in.)61cm (24 in.)
spacing Offset (from top of Gamma Ray
Tool Sub): 263.65 cm (103.8 in.)
2. Neutron Detector, Near Spacing:
He3 2.9 x 10.1 cm (1.125 x 4.0 in.)
32.4 cm (12.75 in.) spacing
Offset: 291.08 cm (114.6 in.)
3. Neutron Porosity:
Neutron porosity offset: 297.18 cm (117in.)
4. Radioactive Source:
5 Ci AmBe 241 neutron source, bullplug
Offset: 320.14 cm (126.04 in.)
Length: 194.1 cm (76.42 in.)
Temperature: 125 C (257 F)
Diameter: 6.35 cm (2.5 in.)
Pressure: 350 kg/cm2 (5,000 psi)
Weight: 28.8 kg (57 lb.)
Logging Speed: 9 m/min. (30 ft./min.)
