The operating procedure for a rotary drilling rig is as follows:#mini borehole drilling machine#
Pre-construction preparation:
Site preparation: Ensure the working surface is firm and level. If necessary, lay roadbed plates or harden the ground to prevent subsidence.
Equipment inspection: Before starting, complete routine maintenance, checking critical components such as hydraulic oil level, cylinder piston rod condition, and shut-off valve handle position.
Safety confirmation: Observe the geological cross-section diagram, mark the locations of underground pipelines (such as gas pipelines and cables) and high-voltage lines, and set up safety warning signs.
Equipment start-up and positioning:
Engine start: Let the engine idle for 2-5 minutes (5 minutes in winter), checking if the instrument panel indicator lights are normal.
Ridge positioning: Move the drilling rig to the drilling position using the crawler system. Use a level to adjust the mast's verticality to ensure drilling accuracy.
Drilling operation:#mini borehole drilling machine#
Initial drilling: The power head drives the drill rod to rotate, relying on its own weight or a pressure device to make the drill bit cut into the formation. Refer to the depth gauge and instruction manual for each drilling depth measurement.
Soil and Rock Loading: The drill bit rotates and cuts through the strata, allowing soil and rock to enter the drill bucket through openings at the bottom and sides.
Drill Bucket Lifting and Soil Unloading:
After the drill bucket is full, the drill rod is slowly lifted while drilling mud is injected to maintain borehole stability.
The drilling rig mast is rotated to dump the soil and rock from the drill bucket out of the borehole, where it is transported to a designated location by a loader.
Repeated Drilling: The drill bucket valve is closed, the drill bit is lowered, and drilling continues, forming a cycle of "drilling-lifting-unloading-re-drilling".
Borehole Quality Control:
Casing Installation: Guide casings are installed according to soil conditions. The casing diameter is 10-30cm larger than the pile diameter, and the top protrudes 0.3-1.5m above the ground.
Verticality Monitoring: Real-time monitoring is conducted using a depth sounder and a verticality gauge. The borehole depth is checked with a measuring rope when the last 2-3 meters of drilling are completed.
Drilling Mud Management: High-quality drilling mud is replenished using a mud pump to maintain pressure balance within the borehole and prevent collapse.
Special Geological Treatment:#mini borehole drilling machine#
Soft Soil Layers: Use long-toothed drill bits with wide tooth spacing to avoid drill bit clogging; clean the mud adhering to the cutting teeth after lifting the drill bit, and replace worn teeth promptly.
Hard Soil Layers: If the single-drill depth is too small, use a small-diameter drill bit to pre-drill a small hole, then enlarge the hole to the design size.
Gravel and Pebble Layers: Reinforce the hole wall with clay balls, and use a double-bottom plate sand-removing drill bit to prevent sand leakage.
Final Drilling and Acceptance:
Bottom Hole Inspection: After reaching the design depth, use a borehole inspector to check the hole diameter and verticality. If the deviation exceeds the standard, adjust the drilling rig or backfill and re-drill.
Sediment Treatment: Perform an initial hole cleaning and depth measurement. After placing the reinforcing cage, perform a second hole cleaning to ensure the sediment thickness at the bottom of the hole meets the specifications.
Equipment Shutdown and Maintenance:
Shutdown Procedure: Gradually reduce the engine speed to idle speed, run for 3-5 minutes, then turn off the power and disconnect the main switch.
Post-maintenance: Clean the sediment inside the drill pipe, check the arrangement of the wire rope, and replace vulnerable parts such as the union or drill pipe.#mini borehole drilling machine#
