Views: 0 Author: Site Editor Publish Time: 2026-01-22 Origin: Site
As a core piece of equipment in pile foundation construction, the rotary drilling rig operates under complex geological conditions and high-intensity workloads, inevitably leading to various malfunctions. Among these, abnormal noises, oil leakage, and insufficient power are the three most common issues that affect construction efficiency. If not promptly diagnosed and addressed, these problems may not only cause equipment downtime but also lead to severe mechanical damage and increased repair costs. This article will analyze the diagnostic techniques and troubleshooting methods for these three types of failures in detail, based on the structural characteristics and operational principles of the rotary drilling rig, providing practical references for on-site operators and maintenance personnel.
The abnormal noise of the rotary drilling rig mostly originates from abnormal friction, vibration, or looseness in core components such as mechanical transmission, hydraulic system, and engine. Abnormal noises from different parts have obvious differences in sound characteristics and occurrence scenarios, and can be troubleshoot through a combination of 'listening, observing, and feeling'.
Classification and Characteristic Identification of Abnormal Noises
Abnormal noises in the mechanical transmission system: These typically manifest as "clunking" impact sounds, "humming" resonance noises, or "whirring" friction sounds, commonly occurring in areas such as drill pipes, slewing bearings, and gearboxes. For instance, impact noises during drill pipe extension may indicate a loose drill pipe locking mechanism or worn guide sleeves; continuous resonance sounds during slewing operations are most likely caused by worn raceways in the slewing bearing, damaged rollers, or loose fastening bolts.
Hydraulic system noise: Predominantly characterized by "hissing" cavitation sounds, "whirring" leakage sounds, or "knocking" noises, often related to hydraulic pumps, hydraulic motors, or pipelines. If cavitation sounds occur after the hydraulic pump starts and are accompanied by unstable system pressure, it may indicate low oil tank levels, clogged suction oil filters, or air leakage in the suction pipe. Knocking sounds during hydraulic motor operation could suggest internal component wear or severe hydraulic oil contamination.
Engine abnormal noise: Common "tapping" valve knock, "rumbling" exhaust noise, or "metal friction" sound. Valve knock is often caused by excessive valve clearance or hydraulic tappet failure; metal friction noise may result from water pump or alternator bearing damage, or abnormal wear of pistons and crankshaft.
Troubleshooting steps for abnormal noise faults
Preliminary positioning: Based on the operating conditions (such as drilling, rotation, and walking) and the direction of sound propagation, narrow down the scope of investigation. For example, if there is only abnormal noise during drilling, focus on checking the drill pipe, power head, and drilling tools; Focus on core components such as the engine and hydraulic pump if there is any abnormal noise throughout the process.
Visual inspection: Check whether the parts in the suspected area are loose, deformed, worn, or have oil stains or metal debris (such as gearbox oil leakage, which may be accompanied by gear wear and abnormal noise).
Auxiliary testing: By changing the operating speed (such as reducing the drilling speed), disconnecting some transmission links (such as temporarily stopping the rotation), observing whether the abnormal noise disappears, and further locking the fault point. For example, if the abnormal noise disappears after disconnecting the hydraulic motor from the slewing support, it indicates that there is a fault in the motor.
Professional testing: If visual inspection fails, use equipment diagnostic instruments to read the operating data of the engine and hydraulic system (such as pressure, temperature, speed), or use ultrasonic testing instruments and vibration analyzers to determine the wear of parts.
The oil leakage faults of rotary drilling rigs mainly occur in the hydraulic system, fuel system, and lubrication system. Oil leakage not only causes waste of oil, but may also lead to insufficient lubrication of components and a decrease in hydraulic system pressure, resulting in secondary failures. The investigation of oil leakage should follow the principle of "easy first, difficult later, and from the surface to the inside".
Common locations and causes of oil leakage
Hydraulic system oil leakage: accounting for more than 80% of oil leakage faults, common parts include hydraulic pipeline joints, sealing rings, hydraulic valves, and hydraulic pump/motor joint surfaces. The main reasons are loose joints, aging or damaged sealing rings, broken pipelines, and worn valve bodies. For example, the loosening of threads in high-pressure oil pipe joints due to long-term vibration, or the aging and deformation of sealing rings due to high hydraulic oil temperature, can cause leakage.
Fuel system oil leakage: mainly occurs in the fuel tank, fuel pipelines, fuel filters, and fuel injectors. It is often caused by aging and cracking of pipelines, inadequate sealing of joints, loose filter bases, or damaged fuel injector seals.
Lubrication system oil leakage: commonly found in engine oil pan, crankshaft oil seal, gearbox drain plug, and grease filling port. The reasons include loose oil drain plug, worn oil seal, and aging and detachment of sealant on the joint surface of the box.
Troubleshooting methods for oil leakage faults
Clean the surface and locate the leakage point: First, clean the oil stains on the surface of the equipment (which can be rinsed with a high-pressure water gun and wiped dry), start the equipment and run for 10-15 minutes, observe the location of the oil leakage, and determine the leakage point. If the leakage point is not obvious, talcum powder can be applied to the suspected area, and obvious traces will form when the oil seeps out.
Distinguish leakage types:
Surface leakage: The oil only adheres to the surface of the parts without dripping, mostly due to loose joints or slight aging of the sealing ring. It can be solved by tightening the joints and replacing the sealing ring;
Dripping: Continuous dripping of oil is often caused by pipeline rupture, severe wear of oil seals, or cracking of the casing. Immediate shutdown and maintenance are required;
Internal leakage: Oil leaks into the interior of the equipment (such as hydraulic oil leaking into the gearbox) without any external traces. It needs to be judged by the pressure and oil quality of the detection system (if gear oil is mixed into hydraulic oil, oil emulsification and abnormal color may occur).
Targeted processing:
Loose joint: Use a torque wrench to tighten according to the specified torque (to avoid thread damage caused by over tightening);
Aging of sealing rings: Replace with sealing rings of the same model and material (high-pressure and oil resistant fluororubber sealing rings should be selected for hydraulic systems);
Pipeline rupture: Replace the damaged pipeline and check for potential aging hazards in adjacent pipelines;
Box cracking or component wear: Minor cracking can be repaired by welding, and in severe cases, the box or related components need to be replaced (such as hydraulic pump housing cracking requiring overall replacement).
Key points for preventing oil leakage faults
Regularly check the oil level and quality to avoid excessive or contaminated oil; Replace vulnerable parts such as sealing rings and sealants on time; The hydraulic system should avoid long-term operation under ultra-high pressure and high temperature conditions; When tightening the joint, follow the principle of "diagonal uniform tightening" to prevent leakage caused by uneven force.
The insufficient power of the rotary drilling rig is mainly manifested as slow drilling speed, weak rotation, difficult walking, or difficulty in starting the engine and slow acceleration. The core causes are concentrated in the engine, hydraulic system, and transmission system, and need to be checked layer by layer from the 'power source - transmission link - executive components'.
Common reasons for insufficient power
Insufficient engine power output: As the power core of the equipment, engine failure is the primary cause of insufficient power. This includes insufficient fuel supply (such as clogged fuel filters, faulty fuel injectors, and leaking fuel lines), clogged intake systems (dirty air filters, faulty turbochargers), abnormal ignition systems (worn spark plugs, faulty ignition coils), and mechanical engine wear (insufficient cylinder compression pressure, aging piston rings).
Hydraulic system failure: Insufficient pressure or flow in the hydraulic system can cause insufficient power to the executing components (power head, swing motor, walking motor). Common causes include hydraulic pump wear (decreased volumetric efficiency), hydraulic valve sticking (abnormal flow regulation), hydraulic oil contamination or leakage (system pressure loss), and accumulator failure.
Transmission system failure: mechanical transmission parts slip or power transmission is obstructed, such as clutch wear, gearbox gear damage, drill rod locking mechanism failure (power transmission loss during drilling), loose or worn walking chains.
Troubleshooting steps for insufficient power
First, check the engine:
Check the fuel and intake system: replace clogged fuel and air filters, check for leaks in the fuel lines, and test the atomization effect of the fuel injectors;
Testing the ignition system: Check the gap and wear of the spark plug, and test the output voltage of the ignition coil;
Measure cylinder compression pressure: If the pressure is insufficient, disassemble the engine to check the cylinder, piston rings, and valve seals.
Re check the hydraulic system:
Check hydraulic oil: Check if the oil level meets the standard, if the oil has deteriorated (such as blackening or impurities), and replace the hydraulic oil and filter element if necessary;
Measurement system pressure: Start the equipment and detect the pressure at the outlet of the hydraulic pump and the inlet and outlet of the hydraulic valve through a pressure gauge. If the pressure is lower than the standard value, check for hydraulic pump wear, hydraulic valve jamming, or oil leakage points;
Check the accumulator: If the accumulator pressure is insufficient to replenish the system pressure, it needs to be inflated or replaced.
Finally, check the transmission system:
Inspect mechanical transmission components: check the wear of clutch plates, transmission oil level and gear engagement status, and tension of walking chains;
Test execution component: Disconnect the execution component (such as the power head) from the transmission system and test the power source output separately to see if it is normal. If the power source is normal, it indicates a malfunction in the execution component or transmission link.
Preventive Maintenance First: Regularly perform equipment maintenance, replace consumables such as engine oil, hydraulic oil, and filters according to the schedule, clean air filters and fuel filters, check the tightness of bolts at various parts, and reduce the probability of failures.
Safety First: When troubleshooting, the machine must be shut down and powered off, and system pressure must be released (e.g., open the pressure relief valve for the hydraulic system) to prevent personal injury caused by oil spraying or unexpected movement of components; when working at heights (e.g., inspecting the top of the drill pipe), safety belts must be worn.
Data-Driven Support: Utilize the equipment's built-in diagnostic system or professional testing instruments to avoid blindly disassembling parts, thereby reducing unnecessary maintenance costs and equipment damage.
Record and Traceability: Establish an equipment failure ledger to record failure phenomena, troubleshooting processes, repair plans, and results, providing reference for subsequent diagnosis of similar failures.
In short, although the abnormal noise, oil leakage, and insufficient power of rotary drilling rigs manifest in different forms, they are closely related to the daily maintenance and operating conditions of the equipment. Operators need to be familiar with the structure and operating characteristics of the equipment, master the diagnostic skills of "listening, watching, testing, and analyzing", achieve early detection, early investigation, and early repair, and maximize the stable operation of the equipment to improve construction efficiency.
