I. Filter element strength test
The strength test of filter elements mainly focuses on their compressive resistance, impact resistance and crack resistance under extreme conditions. The following are the main testing methods and the international standards they are based on:
1. Structural integrity test (ISO 2942)
Test objective: To verify the structural integrity of the filter element in the hydraulic system and ensure that it does not leak or get damaged under normal working pressure.
Test method: By gradually increasing the pressure, observe the structural stability of the filter element under pressure. The "bubble point" test method is usually adopted, that is, a certain pressure of liquid is applied to the surface of the filter element to observe whether there is liquid penetration.
Applicable scenarios: It is suitable for common metal and plastic filter elements in hydraulic systems.
2. Bursting resistance test (ISO 2941)
Test objective: To evaluate the anti-cracking ability of the filter element under high pressure conditions and prevent the filter element from cracking due to excessive system pressure.
Test method: Apply gradually increasing pressure to the filter element until it breaks, and record the pressure value at the moment of breakage.
Applicable scenarios: It is suitable for filter elements used in high-precision hydraulic systems, such as servo valve and proportional valve systems.
3. Axial Load Test (ISO 3723)
Test objective: To assess the axial load-bearing capacity of the filter element and ensure that it does not deform or get damaged due to external loads during installation and use.
Test method: Apply axial pressure to the filter element and observe its deformation and whether there is any leakage.
Applicable scenarios: Suitable for filter elements installed in high-pressure hydraulic systems.
4. Flow Fatigue Characteristics Test (ISO 3724)
Test objective: To evaluate the fatigue life of the filter element during long-term use and ensure that it maintains structural integrity under frequent flow rate changes.
Test method: Conduct more than 100,000 cycle loading tests on the filter element to simulate the dynamic load under actual working conditions.
Applicable scenarios: It is suitable for hydraulic systems that require long-term operation, such as construction machinery and injection molding machines.

Ii. Durability Test of Filter Elements
The durability test of filter elements mainly focuses on their performance stability during long-term use, including filtration efficiency, flow characteristics, and the compatibility of the material with the liquid. The following are the main testing methods:
Passed multiple tests (ISO 16889 / ISO 4572)
Test objective: To evaluate the filtration efficiency of the filter element after multiple passes of contaminants (such as test dust), and to ensure that it can maintain good filtration performance over long-term use.
Test method: By using the online particle counting method, contaminants are continuously injected into the filter element, and the number of particles at the oil inlet and outlet is measured to calculate the filtration efficiency (β value).
Applicable scenarios: It is suitable for filter elements with high cleanliness requirements in hydraulic systems, such as servo valve and proportional valve systems.
2. Pressure Drop Flow Characteristic Test (ISO 3968)
Test objective: To evaluate the pressure drop characteristics of the filter element at different flow rates and ensure its flow stability under actual working conditions.
Test method: Measure the pressure drop of the filter element under different flow conditions and draw the flow-pressure drop characteristic curve.
Applicable scenarios: It is suitable for hydraulic systems that require high flow stability, such as large injection molding machines and steel rolling mills.
3. Compatibility test of materials with liquids (ISO 2943
Test objective: To evaluate the compatibility of the filter element material with hydraulic oil or other liquids and ensure that it does not fail due to chemical reactions during long-term use.
Test method: Immerse the filter element material in hydraulic oil and observe the changes in its physical and chemical properties.
Applicable scenarios: It is suitable for systems that use special hydraulic oils (such as biodegradable oils).

Iii. Testing Equipment and Execution Standards
To ensure the accuracy and consistency of the test, it usually requires the use of professional testing equipment and compliance with international standards. The following are commonly used testing equipment and standards:
Structural integrity test bench (such as WZA-15K)
Function: Through non-destructive testing methods, determine the pore size and filtration accuracy of the filter element, and verify its structural integrity.
Execution standards: ISO 2942, GB/T 14041.1-2007.
2. Multiple tests on test benches (such as DT-500C, DT-6)
Function: Evaluate the filtration efficiency, impurity storage capacity and flow pressure drop characteristics of the filter element through the online particle counting method.
3. Execution standards: ISO 16889, ISO 4548-12, SAE J1858.
Flow fatigue test bench
Function: Simulate the dynamic load of the filter element during long-term use and evaluate its fatigue life.
Execution standard: ISO 3724.

Iv. Test Results and Application Suggestions
1. Test result analysis
Through the above tests, the strength and durability of the filter element can be comprehensively evaluated to ensure that it meets the design requirements in practical applications.
For high-precision hydraulic systems, it is recommended to choose filter elements that have passed the ISO 16889 test to ensure their filtration efficiency and impurity storage capacity.
2. Application suggestions
When choosing filter elements, priority should be given to products that have passed international standard certifications such as ISO 2941 and ISO 2942 to ensure their quality and performance.
For hydraulic systems that need to operate for a long time, it is recommended to conduct regular strength and durability tests on the filter elements to ensure the stability of their performance.

The strength and durability test of the filter element of the hydraulic filter is an important link to ensure its performance stability and reliability. The performance of the filter element can be comprehensively evaluated by following international standards (such as ISO 2941, ISO 2942, ISO 16889, etc.) and using professional testing equipment (such as structural integrity test benches and multiple pass test benches). Selecting filter elements that have passed strict tests and conducting regular maintenance and testing can effectively extend the service life of the hydraulic system, improve the operational efficiency and reliability of the equipment.