The gasoline engine intake valve sediment simulation test machine needs to meet the following technical requirements, including equipment composition, key components, control accuracy, and performance verification:
1、 Equipment composition and core components
Sediment test assembly
Sediment collector: Made of 1060 aluminum plate with a thickness of 4 ± 0.1mm, the surface is flat and defect free, and a thermocouple socket (with an aperture of Φ 1.7 ± 0.1mm) is set in the center, matched with a Φ 1.5 ± 0.1mm thermocouple to ensure temperature measurement accuracy.
Nozzle body: Use an air atomizing fan-shaped nozzle (such as B1/4J+SUF1 type), with the front end of the nozzle at a horizontal distance of 16-17mm from the collector. The spray shape is lip shaped (length 27-32mm, width 5-8mm) to ensure even distribution of fuel.
Plate heater: made of aluminum or copper, with a heating power of 300W, built-in over temperature protection thermocouple, automatically cuts off the power when the temperature exceeds the limit, to prevent overheating and damage.
Clamping device: using pneumatic cylinder clamping to ensure a tight fit between the heater and collector, reducing heat loss; Both sides of the bracket are embedded with polytetrafluoroethylene insulation pads to prevent heat transfer to the bracket.
Test chamber: Sealed design, equipped with glass windows and axial flow fan (air volume 0.6m ³/min) to ensure stable test environment; Connect the exhaust outlet to the recycling system to reduce pollution.
Oil, gas, and electrical control systems
Gas control: The air compressor provides dry compressed air at 0.4-0.8MPa, which is controlled at 80 ± 1kPa and 700 ± 20L/h, respectively, through a pressure reducing and stabilizing valve, pressure sensor, and glass rotor flowmeter.
Fuel supply system: The gear pump or peristaltic pump controls the fuel supply flow rate (4.05 ± 0.05mL/min), and the inlet pipe uses a fluororubber tube (outer diameter Φ 3.2 ± 0.1mm, wall thickness 0.8 ± 0.1mm) to ensure stable fuel delivery.
Automatic control: MCU or PLC control system realizes closed-loop control of temperature, pressure, and flow, supporting one click operation, data recording, and over temperature alarm functions.
2、 Key technical parameters
temperature control
Test temperature: adjustable from 160-195 ℃, factory set at 175 ℃, temperature control accuracy ± 1 ℃.
Heating holding time: 10 minutes to ensure sufficient formation of sediment.
Gas parameters
Air pressure: 80 ± 1kPa, pressure control accuracy ± 1kPa.
Air flow rate: 700 ± 20L/h, flow control accuracy ± 20L/h.
Fuel supply parameters
Fuel supply flow rate: 4.05 ± 0.05mL/min, fuel supply timing of 75 minutes, ensuring complete fuel injection within the specified time.
Electrical parameters
Rated power: 480-800W, voltage 200-240V, 50Hz, power supply fluctuation range not exceeding ± 5%.
Safety requirements: The equipment needs to be grounded for protection, and there should be no vibration, magnetic field interference, or corrosive media around it.
3、 Performance validation and calibration
Equipment Calibration
Calibration of coking agent: Use dicyclopentadiene (purity ≥ 70%) as the coking agent, adjust the dosage to achieve a sediment generation of 2.0 ± 0.2mg (reference agent calibration) or 8.0 ± 1mg (blank calibration).
Calibration cycle: Calibrate every six months or recalibrate after replacing key components such as nozzles and heaters.
Repeatability and reproducibility
Repeatability: Continuous testing of the same sample by the same laboratory, operator, and instrument, with a result difference not exceeding 0.4mg (sediment mass range 0.5-12mg).
Reproducibility: Different laboratories, operators, and instruments test the same sample, and the difference in results does not exceed 0.94mg.
Data recording and output
Automatically record parameters such as test temperature, pressure, and flow rate, and support post test sediment collector photography and test report generation.
Data storage capacity: The host can store ≥ 100 sets of test records and supports USB export or network transmission.
4、 Safety and environmental requirements
safety protection
The test chamber is designed with a sealed seal and equipped with an exhaust gas recovery system to prevent the leakage of volatile organic compounds (VOCs).
Overtemperature alarm function: When the temperature exceeds the set value, the heating power will be automatically cut off and an audible and visual alarm will be issued.
environmental requirements
Exhaust gas treatment: Most of the liquid is recovered through a condensing device, and the remaining gas is filtered through an activated carbon filter before being discharged (VOCs content ≤ 200ppm).
Waste oil recycling: The amount of waste oil recovered in a single test is ≥ 70mL, reducing environmental pollution.