New Online Particle Counting System for Detecting Fuel Filter Cleanliness

The fuel filter plays a crucial role in filtering impurities and protecting the engine within the fuel system. However, during the production, storage, transportation, and installation of the fuel filter, its surface may accumulate a significant amount of particulate impurities. These impurities not only clog the filter and affect its filtration performance but also accelerate engine wear, shortening the engine's lifespan. Therefore, cleanliness testing of the fuel filter is essential.

In recent years, new online particle counting systems have been widely used to test the cleanliness of fuel filters. Below, we will compare two testing methods.

A person is placing filter paper onto the instrument in preparation for filtration.

Limitations of Traditional Testing Methods

Traditional methods for testing the cleanliness of fuel filters mainly use the weighing method, which assesses cleanliness by measuring the weight change of the filter before and after cleaning. However, this method has the following limitations:

Cumbersome operation: It requires multiple steps including disassembly, cleaning, drying, and weighing, which is time-consuming and inefficient.
Poor accuracy: It fails to detect small particles, and is significantly affected by environmental humidity and other factors.
Limited information: Only weight change information can be obtained, and detailed information such as particle quantity and particle size distribution cannot be acquired.

Advantages of New Technology

To address the limitations of traditional methods, we have introduced a new technology for fuel filter cleanliness testing based on an online particle counting system. This technology utilizes optical principles to monitor and count particulate contaminants passing through the filter in real-time, and analyzes their particle size distribution, thereby providing a more comprehensive and accurate assessment of the filter's cleanliness.

Compared to traditional weighing methods, the online particle counting system has the following advantages:

Real-time monitoring: It can monitor changes in filter cleanliness in real-time, allowing for timely testing of potential issues.
High accuracy: It can detect micron-sized particles with high testing accuracy.
High efficiency: The testing speed is fast, significantly improving testing efficiency.
Comprehensive information: It can obtain detailed information such as particle quantity and particle size distribution, providing more comprehensive data support for filter performance evaluation.

Test Results

Table 1: Comparison Analysis of Traditional Test Conditions
Standard	Number of Test Pieces	Test Flow Rate	Test Duration	Collection Filter	System Cleanliness before Testing	Test Results
GB 5923-1986	1 piece	2 times the rated flow	1 h	Pore size 28 μm, fiber diameter 25±1 μm, mesh open area accounts for 28%	(0.4–1.1) μm less than 85 kPa	The mass of collected impurities is obtained by weighing (mg).
ISO 4020-2001	1 piece	2 times the rated flow	1 h		(0.4–1.1) μm less than 85 kPa
SAE J905-1999	4 pieces	Rated flow	Each test piece is rinsed for 30 min, totaling 2 h	40 μm mesh filter membrane	2 mg	The mass of collected impurities divided by 4 (mg).

Table 2: Test Results of New Method for New Type 1# Fuel Filter
Test Time(min)	Particle Size (μm) (Number of particles measured by downstream particle counter per 100 ml)
Test Time(min)	> 5–15	> 15–25	> 25–50	> 50–100	> 100
0.5	653755	34512	7415	612	78
5	759842	45324	8621	702	30
10	812458	46771	8701	652	22
15	611145	32457	6043	568	4
20	302158	14503	2593	347	1
25	287494	11044	2014	301	0
30	258415	9741	2415	211	2
35	251244	9841	2120	76	0
40	123366	4510	1478	25	1
45	54187	2418	743	16	0
50	13547	1208	255	5	0
55	2541	564	52	0	1
60	921	201	13	1	0
Average Value	317775	16392	3266	270	11
Cleanliness Levels for Each Particle Size	11	9	9	8	6
Cleanliness Level	1# Fuel Filter Cleanliness Level: 11 Level

Table 3: Test Results of New Method for New Type 2# Fuel Filter
Test Time(min)	Particle Size (μm) (Number of particles measured by downstream particle counter per 100 ml)
Test Time(min)	> 5–15	> 15–25	> 25–50	> 50–100	> 100
0.5	1974123	525474	91215	7141	4163
5	2041262	565412	94651	8211	2454
10	2172554	555481	91178	8125	1450
15	1756811	482488	87450	6244	232
20	1712456	474121	74159	4157	150
25	1365411	142758	21599	1007	23
30	935155	101114	9524	754	8
35	474513	51214	9499	211	1
40	205546	21410	6477	56	0
45	104551	10151	2584	13	0
50	64245	20419	723	0	1
55	14100	6014	74	0	0
60	4222	1221	17	1	0
Average Value	986535	227483	37627	2763	652
Cleanliness Levels for Each Particle Size	12	> 12	> 12	11	12
Cleanliness Level	2# Fuel Filter Cleanliness Level: > 12 Level

Table 4: Test Results of New Method for New High-Precision Fuel Filter
Test Time(min)	Particle Size (μm) (Number of particles measured by downstream particle counter per 100 ml)
Test Time(min)	> 5–15	> 15–25	> 25–50	> 50–100	> 100
0.5	15411	4257	1065	313	88
5	14741	3102	904	155	10
10	8411	1005	543	66	2
15	4458	418	97	12	0
20	1359	133	18	0	0
25	482	23	6	0	0
30	104	5	0	0	0
35	34	0	0	1	0
40	10	1	0	0	0
45	4	0	0	0	0
50	1	0	0	0	0
55	0	0	0	0	0
60	0	0	0	0	0
Average Value	3463	688	203	42	8
Cleanliness Levels for Each Particle Size	4	4	5	5	5
Cleanliness Level	High-precision fuel filter cleanliness level: Level 5

It can be seen that the new online particle counting system provides a more efficient and accurate method for fuel filter cleanliness testing, effectively enhancing the performance evaluation and maintenance management of the filter.