How Does a Falling Dart Impact Tester Work?
A complete guide to understanding the physics of free-fall impact, the staircase method, and the mechanics of the MLB-01 system.
What Is a Falling Dart Impact Tester?
A Falling Dart Impact Tester (like the MLB-01) is a specialized instrument used to determine the energy required to cause a plastic film to fail under impact conditions. Unlike slow-speed tensile tests, this simulates high-speed shock events, such as a heavy box falling onto a pallet wrap or a bag of rice dropping on the floor.
How Does It Work? (The Mechanics)
The MLB-01 combines precise mechanics with intelligent algorithms.
1. Pneumatic Clamping
The film sample (>150mm x 150mm) is placed between two annular clamps. The MLB-01 uses a Pneumatic System (not manual screws) to apply consistent pressure, ensuring the film is taut and doesn't slip upon impact.
2. Electromagnetic Release
The weighted dart is held at a specific height (0.66m for Method A or 1.5m for Method B) by an electromagnet. This ensures a true "free fall" with zero initial velocity or rotation, which is critical for ASTM compliance.
3. The Impact Event
When released, the dart converts potential energy (E=mgh) into kinetic energy. It strikes the center of the clamped film.
4. Result Observation
The operator observes if the film has ruptured (a visible hole or tear). This "Pass/Fail" result is input into the touchscreen.
5. Staircase Calculation (The Brain)
Based on the input, the system calculates the next weight:
• If it breaks: The system tells you to reduce weight (Delta M).
• If it survives: The system tells you to increase weight.
After 20+ drops, it statistically calculates the 50% Failure Mass (M50).
Why Use the MLB-01 vs. Manual Testers?
• No Calculation Errors: Manual calculation of the Staircase Method formula is prone to human error. The MLB-01 does it automatically.
• Safety: The electromagnetic release keeps the operator's hands away from the drop zone.
• Repeatability: Pneumatic clamping removes the "operator strength" variable.
