Hydraulic System Failures: The "Invisible Killer" of Piling Machine Operation
In the entire construction process of piling machines, the hydraulic system, as the core power unit, its stability directly determines the construction efficiency and safety. The following is an in-depth analysis of common failures of the hydraulic system, helping practitioners to accurately deal with the "power crisis".
(1) Problem Phenomena: The "Triple Alarms" of the Power System
1. Insufficient Pressure: When driving piles, the speed at which the pile body enters the soil significantly slows down, and it may even be unable to penetrate to the designed depth; when the piling machine moves or turns, the power is weak, and the movements are jerky.
2. Excessively High Oil Temperature: The temperature of the hydraulic oil continuously exceeds 80°C, accompanied by the thinning of the oil and an abnormal smell. The equipment can only resume operation briefly after being shut down and cooled.
3. Oil Leakage Risks: Oil leakage occurs at parts such as the tubing joints and the piston rods of the oil cylinders. Obvious oil stains can be seen on the ground. In severe cases, the hydraulic oil level drops below the minimum scale line.
(2) Cause Analysis: From Component Wear to System Imbalance
1. Aging and Wear of Components
- Failure of the Hydraulic Pump:
Due to long-term high-speed operation, the clearance between the gears of the gear pump expands , resulting in insufficient oil suction and pressure attenuation, just like "a leaky bucket that cannot be filled with water".
- Deterioration of Sealing Parts:
After being used for more than 2 years, the sealing rings are likely to harden and crack (the elasticity decreases by more than 60%). The tubing may develop sand holes due to vibration or corrosion (an oil leak will occur when the diameter > 1mm).
- Case:
In a certain construction site, due to the failure to replace the aging sealing rings in a timely manner, more than 50L of hydraulic oil leaked within 3 days, forcing the equipment to be shut down for maintenance and delaying the construction period.
2. Uncontrolled Oil Contamination
- Invasion of Impurities:
Dust, sand, and metal shavings at the construction site enter the system through the breather hole of the oil tank, or foreign objects are left by tools during maintenance, causing the hydraulic valves to get stuck (for example, the spool of the directional valve is stuck by particles).
- Infiltration of Moisture:
During construction in the rainy season, condensed water mixes into the oil, causing the hydraulic oil to emulsify and deteriorate (the oil turns milky white). In a certain bridge project, this led to abnormal wear of the hydraulic pumps of 15 piling machines.
- Data:
Oil contamination can reduce the service life of hydraulic components by 70% and increase the failure rate by more than 5 times.
3. Paralysis of the Heat Dissipation System
Blockage of the Radiator:
The fins of the radiator are covered by mud and dust (coverage rate > 50%), and the heat dissipation efficiency drops by 80%, just like "wrapping a quilt around a radiator".
Cooling Failure:
The fan belt is loose and slips (the rotational speed < 70% of the rated value), and the temperature control valve malfunctions, resulting in the oil not passing through the radiator. The oil temperature will definitely exceed the critical value after continuous operation for more than 4 hours.
Regular Maintenance:
Establish a regular maintenance system for the hydraulic system. Replace aging sealing parts and filters, clean the oil tank and radiator; use high-precision filtering equipment to purify the hydraulic oil.
Fault Diagnosis:
Use monitoring components such as pressure gauges and thermometers to determine the fault points. Repair or replace the severely worn hydraulic pumps and control valves in a timely manner.
Optimal Operation:
Reasonably arrange construction intervals to avoid long-term overloaded operation; add heat dissipation measures in high-temperature environments (such as installing additional cooling fans).
Burst Tubing:
Immediately stop the machine → Turn off the oil pump motor → Plug the ruptured part with an emergency plug → Switch to the standby tubing (spare parts of the same specification need to be prepared in advance).
Oil Temperature Alarm:
Stop the operation immediately → Check the cleanliness of the radiator surface → Start the standby fan for forced cooling → If the oil temperature does not drop within 30 minutes, professional maintenance is required.
Tianwei Service Reminder: If you need a special inspection of the hydraulic system or a customized maintenance plan, You can contact our sales staff，We will dispatch engineers to provide on-site diagnosis services.
—— Tianwei Piling Machine Academy, Making Construction Technology Accessible ——
