Before the trenchless drilling rig starts construction, the following preparations must be made to ensure the smooth progress of the construction:
1. Construction site detection: Use detection instruments to find out the direction, depth and nature of the original underground pipe network, and make a mark; then verify with the help of municipal archives and manual on-site surveys.
2. Check that the oil level of the hydraulic oil tank should not be less than 1/2 of the oil standard; add sufficient lubricating oil or grease according to the requirements of the lubrication parts of the drilling rig.
3. Do the maintenance of the diesel engine, replace the three filters and oil regularly, add antifreeze to the water radiator of the diesel engine, and replace it regularly. Before starting up, check whether the diesel fuel is full, whether the antifreeze fluid is sufficient, whether the oil level is normal, and whether the battery electrolyte is sufficient. Confirm that the diesel engine throttle is in the idle position.
4. Check whether the handles of the valves of the hydraulic system and all the electronic control switches are in the neutral position, and whether the handles of the mud pump are in the neutral position.
5. Confirm the normal operation of the guide, whether the battery of the instrument and probe is sufficient, and the accuracy of the positioning and orientation information (depth, vertex angle and inclination angle).
A few tips before oriented construction:
1. The first is the accuracy of the probe’s work
Take the widely used DCI instrument as an example. The 3-meter calibration is a 3-meter reference for the probe. All measurement data after that are based on this value. Therefore, it is necessary to ensure the accuracy of the 3-meter calibration. The probe is loaded into the probe chamber and calibrated together with the pilot bit, and the surrounding environment interference is as small as possible. The probe calibrated in this way has higher measurement accuracy.
2. No probe is installed for the inspection along the drilling line. It is very helpful to the construction to use the receiver to check the environmental interference along the drilling route. Lower, then the experienced construction personnel will drill the hole to the specified depth before 150 meters, and adjust the drilling angle. When there is environmental interference at 150 meters, the receiver cannot receive the signal from the probe normally. , Adopt the method of drilling without tilting and only rotating. After drilling through 160 meters, the receiver can get the signal again before proceeding with normal drilling.
3. Is it impossible to construct when the receiver only has signal strength? In some constructions, due to exceeding the sounding distance of the probe or due to surrounding interference, sometimes it may happen that there is only signal strength on the receiver, but no parameters such as clock face and tilt angle. Is it impossible to construct at this time? In fact, it is not. Experienced construction personnel will roughly judge the position of the probe based on the peak and valley values of the signal, compare it with the drilling axis to see if there is a deviation, and gradually restore normal signal transmission through subsequent operations such as reducing the depth. Receive status.
4. When using mud, please remove the mud from the drill pipe first. If there is mud inside the drill pipe, it is easy to cut the outer skin of the wire under the drive of high-speed mud and cause the probe to burn.
5. Some details in the wired-oriented construction. In the wired-oriented construction, the middle wire is very important. In the trenchless construction, we generally choose 6 square wires. The wires on the market generally have 19-core hard wires and 100 For the core cord, we should choose the cord for construction.
In addition, whether the purchased wire can meet the construction needs, we should test the usability of the wire when we buy it. The eddy current effect of the coiled wire will greatly reduce the current conductivity. Therefore, if the construction distance exceeds 1000 meters, then the test The wires must be connected in series with 5 coils of wires (100 meters per coil). If there is a signal display, it proves that the wires are available. If there is no normal display, please buy new wires as soon as possible to avoid unnecessary losses. In addition, the protection requirements for the wires are also very high. The first is the waterproofing of the wire joints. Please use a heat-shrinkable tube with hot melt glue to prevent the mud from entering the probe and burning the probe; it is recommended to increase the wire every 200 meters during long-distance construction. Due to the long-distance construction drill pipe rotating in the hole, the wire will continue to rotate in the drill pipe, which is prone to accidents of de-jamming and wire breaking.