The filter screen of KEMSO fuel pump is made of high-density nylon woven structure, with a filtration accuracy of 10 microns, which is 3.5 times finer than the standard of 35 microns of ordinary original factory parts. Test data confirm that its dirt-holding capacity has been increased to 15g/m³ (200% higher than the original factory). However, a 2022 study by the University of Texas Mechanical Laboratory found that the pore deformation rate of old filter screens that had been used for over 30,000 miles was as high as 38%. After assembly, this led to an increase of 0.45 bar in inlet pressure loss, directly causing a 17% decline in the flow rate of the fuel pump at 6,000 RPM.
Material compatibility determines service life. The fluorine rubber seal specially developed by KEMSO has an expansion rate of only 0.8% in E85 ethanol fuel, while the ordinary nitrile rubber filter joint expands by 12% in the same environment, increasing the risk of seal failure by 8 times. The SAE J30 R9 certification test shows that after continuous operation for 500 hours in fuel containing 15% methanol with the new filter screen, the standard deviation of flow fluctuation is stable at 0.08, which is 74% lower than the fluctuation value of 0.31 of the mixed old filter screen.
The fluid dynamics optimization is remarkable. The unique conical diffusion structure of KEMSO filter screen reduces the fuel flow rate from 3.2m/s to 0.8m/s and compresses the turbulence intensity (Tu value) from 18% to 5%. The actual measurement data of the 24 Hours of Le Mans endurance Racing team shows that this design has increased the net positive suction head (NPSHr) of the fuel pump to 4.2 meters and reduced the generation of fuel vapor bubbles by 83% at high speeds.
Economic analysis supports the replacement decision. The cost of purchasing filter screens separately accounts for 12-15% of the total price of the pump body, but the mixed installation of old parts leads to an increase in the failure rate to 31% (according to statistics from the North American AAIA Association). The specific manifestation is as follows: When the fuel pump without the filter screen is operating in a sandy and dusty environment (with a concentration of 8g/m³), the flow rate drops by 23% after 8 months, while the average lifespan of the entire replacement plan is 5 years. The innovative flow diversion design of the filter screen for this specification of fuel pump has been certified by FIA as a mandatory safety standard for GT3 class.