Far-Rea Corp

Product Detail
MWD Tools parts
Detail

The FR-DGA, Directional Gamma Tool, is aTungsten-collimated version of the NGT-T gamma tool.   These tools aresometimes referred to as “focused” or “shielded” gamma tools.   In thisdesign a 67° “window” is machined along the length of the Tungsten shield thatsurrounds the crystal/phototube detector.   Only gamma ray entering fromthe formation through this window can be detected and counted.   Whenaligned with the tool face or other physical reference, the FR-DGA indicates thedirection from which gamma ray energies originate.The FR-DGA is interchangeable with the standard FR-NGT-T gamma tool.   It is same overall length and diameter.   Becauseof the required thickness of the Tungsten shield, the Nal(TI) scintillatorcrystal is of a smaller diameter.   The length is increased to 6.0” however,to deliver an equivalent volume of crystal material as in the FR-NGT-T to providemaximum sensitivity.

FR-DGA Specifications技术指标

Detector

探头

Nal(TI) Scintillator Crystal碘化钠晶体

0.625” Diameter   X 6.0”   Length

0.625” 直径X 6.0” 长度

Photomultiplier光电倍增管

R3991A (Hamamatsu)

Mechanical

机械

Diameter (OD)直径

1.36”

Length (make-up)长度

13.67”

Weight重量

3.0 lb.

End Connectors端点接头

Micro-D Subminiature, 15-Pin15MDM

Material材料

Aluminum Alloy(chassis) 铝合金(外壳),钨合金(屏蔽)

Performance

性能

Sensitivity灵敏度

0.65 CPS/API

Accuracy精度

+/- 5% to 300°F
   +/- 10% to 350°F

Front/Back Count Ration

前后计数比

2.4

Angular Resolution (8” hole)角分辨率(8寸井眼)

75°/360°

Max API @ 5% PPU error

15,000 API

Thin-Bed Resolution (8” hole   Diameter)

最小分层率(8寸井眼)

8.8”

Environmental

环境

Operating Temperature

工作温度

0°F to 350°F

Survival Temperature (reduced   accuracy)

生存温度(降低的精度)

-40°F to 400°F

Heat/Cool Rate, Max.

最大加温/冷却率

5°F per minute

Vibration (3 axis) 50-1000 Hz,   Random

震动(3轴)50-1000 赫茨随机

20G RMS

Shock (Z axis)

冲击(Z轴)

500 G, 0.5 mSec

Shock (X or Y axis)

冲击(X Y轴)

1000 G, 0.5 mSec

Power Requirements

功率要求

DC Input Voltage直流输入电压

17-48 VDC, 50VDC Max.

Tool Current仪器电流

8-11 mA

Output Signal

输出信号

Negative Pulse

负脉冲

+5V to GND, 5 uSec width