1. Definition and core functions
The whole vehicle rain test chamber, also known as the whole vehicle rain test room or sealing test room, is a large artificial simulated climate environment testing equipment. Its core function is to simulate various water testing conditions such as natural rainfall, strong water spraying, and high-pressure flushing, used to test the sealing performance of the entire vehicle (sedan, SUV, bus, etc.) or large assemblies.
Simply put, it is used to answer a key question: "Can the body, doors, windows, lighting fixtures, and other parts of a vehicle effectively prevent water from seeping into the interior during rainy weather, car washing, or water immersion
2. System composition and working principle
The whole vehicle rain test box is a complex system engineering, mainly composed of the following parts:
(1) Test box and room structure
Structural form: usually a through type (vehicles can enter and exit in a straight line) or a dead end type (vehicles need to tilt out after entering).
Building Material: Made of stainless steel plate or high-quality galvanized steel plate, filled with insulation material (such as polyurethane) to ensure rust prevention, insulation, and corrosion resistance of the building.
Door: Electric or manual sliding door with good sealing performance.
Pit and drainage system: The ground adopts anti slip grating panels, and the lower part is equipped with large drainage ditches and reservoirs to ensure the rapid recovery and recycling of sprinkler water.
(2) Spray system (core system)
This is the key to implementing different testing functions, typically consisting of multiple independent subsystems:
Top spray system: Simulate natural rainfall. Composed of pipes and nozzles, evenly arranged at the top of the room, producing vertically falling raindrops.
Side spray system: Simulate crosswind rainfall. Installed on both sides of the building, the nozzle sprays water at a certain angle towards the side of the vehicle.
Front/rear spray system: Enhanced spray is applied to the front (windward side) and rear of the vehicle.
Bottom spray system: Simulate vehicles driving over waterlogged roads and spray the chassis and wheels.
Strong jet spray system (optional): Simulate high-pressure car washing or harsh road conditions. Use high flow, high-pressure nozzles to spray at designated locations and with high intensity on key sealing areas such as door gaps, windows, and door handles.
Nozzle: Typically an adjustable spiral nozzle capable of producing a uniform and continuous water curtain.
(3) Water supply and circulation filtration system
Water storage tank/reservoir: stores a large amount of experimental water.
Water pump group: using multi-stage centrifugal pumps, etc., to provide stable and different pressure water sources for spraying in different areas.
Pressure regulation and display device: Accurately control the pressure of each spray pipeline to meet different testing requirements (such as pressure range from~70kPa for simulating light rain to~1000kPa for simulating strong spraying).
Water filtration system: It includes multi-stage filters (such as sand filter and precision filter) to filter impurities in water, prevent nozzle blockage, and ensure clean water quality.
(4) Electrical control system
Control method: PLC (Programmable Logic Controller) and touch screen are used as the control core.
Control function:
Manual control: It can independently start and stop any spray area.
Automatic program control: preset standard testing programs (such as national standards and enterprise standards), one click start, automatically complete the switching of spray time, pressure, and area.
Parameter monitoring: Real time display of water pressure, flow rate, time, water temperature and other parameters.
Safety protection: equipped with leakage protection, motor overload protection, water shortage protection, etc.
3. Main experimental standards and testing methods
The design of the equipment strictly follows domestic and international automotive industry standards, commonly including:
Chinese National Standard: GB/T 12480- Test Method for Rainproof Sealing of Passenger Cars
Enterprise standards: Major automakers (such as Volkswagen, General Motors, Toyota, etc.) have their own stricter factory standards.
Other standards: such as ISO standards, etc.
Typical testing process:
The vehicle enters the test chamber and parks at the designated location.
Close the trunk door and place absorbent paper or arrange for inspection personnel at key locations inside the car, such as the driver's footrest or the trunk.
Select or set the test program on the control panel (e.g. top exposed to rain for 15 minutes, pressure X kPa; Followed by a 5-minute strong jet injection.
Start testing, the system runs automatically according to the program.
After the test is completed, the vehicle is driven out and the inspector immediately enters the car to check for any water seepage or dripping, and records the results.
4. Key performance indicators
Spray intensity: The amount of water sprayed per unit area per unit time (mm/min), adjustable.
Spray pressure: The pressure in each spray area can be independently adjusted and controlled, with high stability.
Water level uniformity: The degree of uniformity of water distribution on the rainy surface of a vehicle.
Water conservation and recycling capacity: An efficient water circulation filtration system significantly reduces water resource consumption.
Control system accuracy and reliability: Ensure that the testing process is strictly repeated according to standards.
5. Application Fields
Automobile manufacturers: Sealing verification during the new car development phase, quality sampling at the end of the production line.
Automotive parts supplier: Conduct sealing tests on assemblies such as doors, windows, sunroofs, and lighting fixtures.
Quality supervision and inspection agency: Conduct quality assessment on commercially available vehicles.
Special vehicles: require higher waterproof and sealing performance.
Summary:
The whole vehicle rain test chamber is a crucial quality assurance equipment in the development and production process of automobiles. It constructs a controllable and reproducible simulated rainfall environment to scientifically and objectively evaluate the sealing performance of the entire vehicle, effectively avoiding interior damage, electrical failures, and customer complaints caused by water leakage issues. It is a key link in ensuring the quality and reliability of automobiles.