Horizontal Directional Drilling Machin's Autumn Construction Maintenance Guide for HDD Contractors-1
Horizontal directional drilling, as a core technology for modern trenchless pipe laying, plays an irreplaceable role in urban infrastructure construction. While autumn is prime construction season, it also presents multiple challenges, including drastic temperature fluctuations, complex soil characteristics, and increased construction risks.
I. Before starting: Force preheating to avoid cold starts
1. Check that all fluids (diesel, engine oil, and hydraulic oil) are winter-grade. When the ambient temperature drops below -10°C, it is recommended to use 46# low-temperature, anti-wear hydraulic oil, and switch diesel to -10# or -35# (depending on the local minimum temperature). In cold regions, it is necessary to replace the engine oil with a dedicated oil (5W-30 or 10W-30 is recommended, adjusted according to local low-temperature conditions) to reduce the low-temperature viscosity and ensure smooth engine starting and lubrication.
2. Check the engine antifreeze to ensure that its freezing point is 5-10°C below the local minimum temperature. If the freezing point is below the standard, it must be completely replaced to prevent ice formation and cracking of the radiator.
3.
Regularly clean the engine fins and air intake grille from fallen leaves and
dust to prevent blockage and heat dissipation. This is especially true in areas
with heavy leaf fall in autumn. Clean the engine antifreeze once daily after
operation.
4.
Check water and hydraulic lines for cracks caused by freezing, and check tires
(or tracks) for ice and blockage. Clear any snow or ice from the equipment
surface and work area.
5. Enable the equipment's preheat function (if available). If the preheat function is disabled, idle the machine for 5-10 minutes until the water and oil temperatures rise above 30°C before operating. Never operate the machine at full capacity.
II. During construction: Smooth operation and monitoring status
✅ Operations
(drill pipe pulling, rotation, and pullback) must be slow and steady. Avoid
sudden increases in load and prevent sudden increases in hydraulic system
pressure due to high oil viscosity.
✅ Monitor the
instrument panel to ensure the water temperature (normally 60-80°C) and oil
temperature (normally 30-65°C) are within the lower limits. If temperatures are
too low, shut down the machine and allow it to idle to warm up. Do not operate
with faults.
✅ If the machine is suspended (for more than 15 minutes), maintain idle speed to prevent oil solidification and blockage in the pipelines.
III. Construction
Control: Adapting to Autumn Soil Characteristics
-Preventing Hole
Collapse and Controlling Hole Shrinkage
✅ 1. In light of reduced rainfall and dry, loose surface soil
in autumn, adjust the mud mix in advance: Based on the original formula,
increase the mud viscosity appropriately (recommended increase: 0.5-1
centipoise). A small amount of a thickener (such as carboxymethyl cellulose)
may be added to enhance the mud's wall protection and prevent hole collapse.
✅ 2. In the event of autumn rain, clean drainage channels
around the construction site before drilling to remove any accumulated water.
This prevents rainwater from seeping into the working stratum, causing a sudden
increase in soil moisture, a decrease in bearing capacity, and potentially
causing hole collapse.
✅ 3. During drilling, monitor the return flow and concentration of the mud in real time. If the return flow decreases or the mud becomes thinner, immediately reduce the drilling speed, replenish high-viscosity mud, and wait until the hole stabilizes before resuming drilling.
IV.-Dynamic adjustment of drilling
parameters
1. When
operating in dry formations, due to increased soil friction, the drilling speed
should be reduced (by 20%-30% compared to the normal summer speed). At the same
time, the mud flow rate should be appropriately increased to enhance cooling
and debris removal, preventing overheating of the drill pipe or mud clogging
the borehole, which could lead to sticking.
2. When
operating in soft formations, due to the diurnal temperature difference, the
soil tends to become "harder at night and slightly softer during the
day." Therefore, the torque should be dynamically adjusted based on the
formation hardness: In the morning, when the temperature is low, the drilling
torque should be appropriately reduced (to prevent overloading the drill
string); as the temperature rises in the afternoon, the torque should be gradually
restored to the normal value.
3. When
drilling through sand or gravel layers, in addition to adjusting the mud mix,
the single drilling distance should be shortened. If necessary, casing should
be run to protect the borehole to prevent instability caused by autumn dryness.
V. Personal Safety and Protection: Addressing Climate Differences
1. Wear layered, warm workwear (a breathable, quick-drying inner layer, a warm fleece midlayer, and a windproof, waterproof outer layer). Wear a full set during low temperatures in the morning and evening (usually below 10°C). Layers can be added or removed as temperatures rise during midday to prevent catching a chill or wind-cold from sweating.
2. Wear non-slip, insulated gloves during work to prevent frostbite from contact with low-temperature equipment. These gloves also increase friction between your hands and the operating handles, preventing hand stiffness that can affect operational accuracy.
3. When working at night or early in the morning, wear a reflective helmet and vest to ensure mutual recognition and avoidance of passing vehicles, reducing the risk of collisions.
4. Conduct a daily pre-shift inspection of the construction site: remove frost, ice, or fallen leaves from the drilling rig's path and work platform. Install anti-slip steel plates on ramps and muddy areas to prevent equipment slipping and falls. 5. Check on-site lighting equipment (such as searchlights and emergency lights) to ensure sufficient brightness during night operations, and that the lighting range covers the drilling area, mud pool and equipment operation area to avoid safety accidents caused by obstructed vision.
