The instrument is special equipment designed and made to inspect quality of borehole of concrete pile. It is mainly used to inspect quality of borehole, such as borehole diameter, depth, verticality, wall shape, and dreg at bottom of borehole, in the construction site of high building, airport, bridge, highway, high-speed railway, harbor, and dock.

Adopts computer controlling techniques, and communicates with inclinometer probe through serial port, so it can display all test data and curves in real time to realize digitalization of quality inspection for borehole of concrete pile. It is simple to be operated, beautiful, and convenient and rapid to save and process test data. If equipped with a portable printer, it can print out test data at determination site, so it is convenient to make rapid inspection report or borehole quality report. This greatly improves working efficiency and quality.

The system has been used in national important construction projects, such as shanghai subway, shanghai superhighway, shanghai grand theater, east china sea bridge, sutong bridge, jiangyin bridge, hangzhou bay bridge, and beijing-Shanghai express railway, and it has been used in the oversea market, such as United Arab Emirates, and Indonesia, etc. It has made excellent social and economic benefits.

System configuration:

1. JJC-1D Controlling case

2. JJY-2 (or JJY-5) Caliper

3. JC-1B Electric Winch and Pulley;

4. JNC-1 Dreg Tester

5. JJM-1 High Precision Inclinometer

6. Laptop (With portable printer) (optional);

Technical parameters

1. Borehole diameter measurement range:

(1) Ф500mm～Ф1600mm (JJY-2); If equipped with an extending leg of 200 mm, its measurement range can be extended to 2000 mm;

(2) Ф1500mm～Ф2500mm (JJY-5); If equipped with an extending leg of 770 mm, its measurement range can be extended to 2800 mm;

2. Borehole diameter measurement error:

(1) ±15 mm (JJY-2);

(2) ±25 mm (JJY-5);

3. Current for caliper: 10 mA;

4. Sensitivity of caliper: ≥100mV/10cm (when current is at 10 mA);

5. Cable length: 100 m (maximum is 125 m);

6. Tension of cable: 0.35t (It will broken at 0.65 t);

7. Drag thickness determination:

(1) Distance interval between electrodes: 0.02m±0.5mm;

(2) Measurement error of electric resistance: ≤5%;

8. Verticality determination:

(1) Measurement range: 0～10°;

(2) Resolution: 0.01°;

(3) Measurement error: ≤±0.1%;

9. Depth indication error:  ≤1‰;

10. Working temperature:

(1) Measurement probes: 0～50℃;

(2) Controlling case: -10℃～45℃

(3) Relative humidity: <85%;

11. Pressure endured by caliper: ≥3Mpa;

12. Power supply: AC 220V, 50 Hz, 50 W;