Compression test: Place the sheet metal welding bottom box on a professional pressure testing machine platform to evenly stress the top surface of the bottom box. Gradually increase the vertical downward pressure to simulate the heavy object squeezing scenario that may be endured in actual use. For example, in industrial equipment, other
components may be stacked on top of the bottom box. Use the pressure sensor to monitor the pressure value in real time and observe the deformation of the bottom box during the pressure increase process. When the deformation reaches the specified limit value, or there are obvious signs of damage such as weld cracking and plate cracking, record the pressure value at this time as a compressive strength indicator to determine whether the bottom box meets the corresponding strength requirements.
Bending test: Use three-point bending or four-point bending test methods. Place the sheet metal welding bottom box horizontally, place a support device at a specific position in its length direction to form a fulcrum, and then apply a concentrated force at the corresponding position above the bottom box. For bottom boxes with a certain length that may be subjected to lateral bending loads, such as bottom boxes used to support long strips of equipment, this test simulates its stress state in actual use. Similarly, displacement sensors and strain gauges are used to measure the deflection and strain of the bottom box, and the changes in the welds and plates during the bending process are observed until fracture or excessive deformation occurs, and the bending strength is measured to ensure the reliability of the bottom box under bending conditions.
Impact test: Using an impact tester, a pendulum with a certain mass is dropped from a specific height to impact the key parts of the bottom box, such as corners, sides, and other relatively weak areas that are easily impacted in actual use. This simulates the scene of transportation, installation or accidental collision to test the ability of the bottom box to withstand instantaneous impact. Observe whether the bottom box has cracks, dents, weld detachment and other damage after the impact. If the bottom box can maintain structural integrity under the specified number of impacts, it means that its impact strength is qualified and can adapt to a relatively harsh use environment.
Fatigue test: By simulating the performance changes of the sheet metal welding bottom box under long-term repeated stress. Periodic pressure, tension or bending moment is applied to the bottom box. The magnitude and frequency of the loading force are set according to the expected use conditions of the bottom box. For example, the bottom box of an electronic device may be subjected to vibration stress caused by frequent start-up and stop of the equipment. After hundreds or thousands of cycles of loading, check whether the bottom box has fatigue cracks, loose solder joints, etc., to evaluate its fatigue life and ensure reliable strength during its service life.
Drop test: The bottom box that has been assembled and placed with a certain simulated load is dropped freely from a predetermined height to the specified ground material in different postures, such as the front, side, corner, etc., to simulate accidental drops during transportation and installation. Check the degree of damage to the appearance of the bottom box and the integrity of the internal structure. If the components are firmly connected and there is no functional damage, it proves that it has a certain ability to resist falling, ensuring the quality of the product during circulation.
Vibration test: Fix the bottom box on the vibration table, set the vibration conditions according to the vibration spectrum, acceleration and other parameters in the actual transportation or working environment, and vibrate continuously for a period of time. This test is for products that work in a vibration environment, such as vehicle-mounted bottom boxes and aerospace equipment bottom boxes. Observe the looseness of welds, displacement of parts, resonance damage, etc. during the vibration process of the bottom box to ensure that its structural strength can withstand long-term vibration.
Combined loading test: Considering the complexity and diversity of actual usage scenarios, sometimes the bottom box will be subjected to multiple types of loads at the same time. For example, in industrial machinery, the bottom box may be subjected to both upper pressure and lateral impact. By designing a special test fixture, we can simultaneously apply different directions and different types of loads to the sheet metal welding bottom box to simulate the worst working conditions and comprehensively test the comprehensive strength performance of the bottom box to ensure that it can still work normally under complex forces.
