Proper installation and use of an oil bypass filtration system maintains hydraulic fluid cleanliness. This ensures long-lasting performance of your hydraulic pumps, hydraulic valves, and other components. This user manual is specially designed to simplify the core operations for you. From installation and adaptation to daily maintenance, it provides clear steps to help you avoid contamination risks and operational mistakes.
Detailed Instructions for Using the Oil Bypass Filtration System
Preparatory Work
Installation is fundamental to stable system operation and must be tailored to flow rate, pressure, hydraulic oil type, and site conditions.
Installation Location Selection
Prioritize installation in low-pressure zones of the main system, such as the tank return area or low-pressure branch lines. Avoid drawing oil from high-pressure lines, such as pump outlets. Low-pressure extraction reduces bypass pump load, preventing pump damage or line leaks caused by excessive pressure.
Ensure sufficient operational clearance. Allow at least 50 cm of space for filter element replacement and pipeline maintenance. Keep the unit away from heat sources like engines or heating devices. Excessively high oil temperatures impair filtration efficiency; oil temperatures exceeding 60°C reduce the filter element’s adsorption capacity.
Connection of Pipelines and Valves
You should choose piping that is compatible with the bypass pump capacity. Don’t use too small diameter pipe, and it will cause inadequate flow or excessive pressure loss.
When installing, connect the piping in the following sequence: main system inlet → bypass pump → filter → main system return. At the entrance, you should install a coarse filter with 100-150 mesh to block large particles to protect the bypass pump. And install a check valve to the outlet side to keep the main system oil back.
All joints are sealed with sealant or O-rings. Ensure all seals are made of materials compatible with hydraulic oil. This prevents leakage that could lead to fluid contamination or reduced flow rate.
Electrical System Wiring
The wiring of the bypass pump motor must comply with electrical specifications. 380V three-phase electricity needs to be grounded, and 220V single-phase electricity requires an added leakage protection device. At the same time, it needs to be linked with the main system control cabinet. When the main system is started, the bypass filtration should be initiated 30 seconds later to avoid excessive load on the power grid upon simultaneous startup.
If the system has intelligent monitoring, you also need to connect the signals to the main control system and set the alarm threshold. For example, an alarm will be triggered when the filter element pressure difference is ≥ 0.3 MPa, and a maintenance prompt will be given when the ISO cleanliness exceeds 18/15.
Startup Phase
Before startup, a comprehensive inspection is required to avoid running the equipment without load or with excessive load.
Pre-Start Inspection
- Oil Inspection
You need to confirm that the oil level in the main system is between the minimum and maximum marks. The viscosity of the oil should meet the requirements; abnormal viscosity will affect the oil suction of the pump. If it is a new system, the air in the pipeline needs to be drained first. Open the exhaust valve of the filter until no bubbles overflow.
- Component Inspection
You should verify that the filter element is correctly in place. The filter element sealing ring needs to fit tightly against the housing to prevent the unfiltered oil from flowing directly. All valves are in the “open” position. The oil intake valve and the return oil valve are fully opened, and the throttle valve is adjusted to the maximum flow rate.
Step-by-Step Startup and Debugging
- Step 1
Start the bypass pump without load, disconnect the oil inlet valve of the filter, and let the pump idle for 30 seconds. You need to check if the motor rotation direction is correct. It should be consistent with the label on the pump body. Reversing will result in no flow. Once there is no abnormal noise, turn off the pump.
- Step 2
Open the oil inlet valve of the filter, restart the pump. Slowly adjust the throttle valve and adjust the bypass flow to 10%-20% of the main system flow. Confirm the flow is stable using a flow meter.
- Step 3
You need to monitor the pressure. For example, the pressure at the outlet of the bypass pump should be ≤ 1.0 MPa, and the pressure difference between the inlet and outlet of the filter should be ≤ 0.1 MPa. This is normal. After running for 10 minutes, check that there is no leakage at the pipe joints and no bubbles in the oil at the return oil port. This completes the startup.
Precautions for Using the Oil Bypass Filtration System
Selection and Adaptation
- Filter Precision Matching
You need to select the filtration precision based on the sensitivity of the main system components. For example, gear pumps may require 5-10μm, while rugged equipment like agricultural machinery can use 10-20μm. Excessively high precision may cause frequent clogging of the filter element, while insufficient precision fails to meet purification requirements.
- Flow Matching
The bypass flow rate should be 10%-20% of the main system flow rate. An excessively low flow rate reduces purification efficiency. For example, if the main system flows at 100 L/min and the bypass only at 5 L/min, it would take 10 hours to filter the oil once. An excessively high flow rate increases energy consumption and may affect the main system pressure.
- Oil Compatibility
Filter element materials and seals must match the fluid type. For instance, synthetic oils require fluorocarbon rubber seals, while biodegradable oils necessitate specialized filter elements. Avoid material swelling that could cause leaks or filter element failure.
Pollution Prevention
- Prevention of Pollution During Installation and Maintenance
When you disassemble the pipeline or filter element, you should wipe the interface with clean cotton cloth. Do not use cotton yarn as it will leave fibers. New filter elements should be unpacked in a clean environment to avoid exposure to dust. After installation, the air in the pipeline should be drained. Bubbles will carry the dust in the air into the oil.
- Avoid Mixing Oil Fluids
Do not mix different brands or types of hydraulic oil. You need to add the oil fluid consistent with the main system, and it needs to be filtered through a filter before being added.
Timely Detection of Abnormalities to Prevent the Expansion of Faults
- No Flow or Insufficient Flow from the Pump
You need to first check whether the coarse filter screen at the oil intake port is clogged and whether the motor rotation direction is correct. If the pump makes noise, it may be that air has entered the pump or the bearings are worn, and you need to release the air or replace the bearings.
- Reduced Filter Element Differential Pressure
This may indicate filter element damage. You need to disassemble and inspect the filter element for cracks. It could also be caused by poor end cap sealing, requiring re-tightening of bolts or replacement of the seal ring. Immediate shutdown is required to prevent unfiltered oil from entering the main system.
- Oil Emulsification and Blackening
For emulsified oil, you need to check if the main system cooler is leaking and if water has entered the oil. Replace the dehydration filter element. For blackened oil, check if the main system components such as the hydraulic pump have severe wear. You need to first repair the main system fault and then replace the filter element.
Special Scenarios
- In Dusty Environments such as Mines and Construction Sites
You need to install dust covers at the pump intake and outside the filter housing. Also, shorten the cleaning cycle of the coarse filter.
- In Humid and Salt-Spray Environments such as at Sea
Your filter housing needs to be treated for corrosion prevention. Choose a corrosion-resistant motor. At the same time, regularly inspect the seals to prevent rusting that leads to leakage. The oil moisture detection cycle should also be shortened.
- In Low Temperature Environments
You need to select oil with low viscosity. Before starting, use a heater to preheat the oil to avoid the problem of too high oil viscosity causing difficulties in pump oil intake.
Conclusion
You will be able to successfully install and use the oil bypass filtration system by following the usage guide on this page. Choosing the appropriate oil filtration system can better protect your hydraulic equipment. It can also precisely control the production efficiency and costs. If you have any questions during the installation and use process, you can contact us. We will provide professional technical support.
