Step-by-Step Guide to Using Dart Impact Tester

Introduction to Dart Impact Testing by Pacorr

Pacorr is a trusted name in the testing equipment industry and a recognized dart impact tester manufacturer offering reliable solutions for assessing plastic film durability. When it comes to packaging integrity, evaluating the material’s ability to withstand sudden impacts is essential.

A Dart Impact Tester helps in determining the energy required to rupture a plastic film or sheet by the free-fall of a standard projectile. This guide offers a step-by-step approach to operating the Dart Impact Tester effectively, ensuring precise testing outcomes that help industries improve packaging performance and minimize failures during product handling or shipment.

What is a Dart Impact Tester and Why is It Used?

A Dart Impact Tester is a quality testing instrument that evaluates the impact resistance of thin plastic films by simulating free-fall drop conditions. The tester assesses the minimum energy required to cause failure (rupture or puncture) in a test specimen.

Industries use this testing method to:

• Analyze packaging film strength
• Ensure transportation durability
• Meet regulatory compliance
• Improve product quality assurance

Pacorr, as a dart impact tester manufacturer, ensures each model adheres to globally accepted standards like ASTM D1709, making it ideal for R&D labs, packaging manufacturers, and quality control teams.

Key Components of a Dart Impact Tester

Understanding the key parts of the tester helps ensure accurate and efficient testing:

• Dart Head (Projectile): Usually hemispherical in shape and attached to a shaft.
• Weights: Modular weights attached to increase mass for various testing intensities.
• Drop Mechanism: Mechanism to release the dart from a standard height.
• Clamping Fixture: Holds the plastic sample securely in place.
• Drop Height Scale: Graduated scale to set the exact drop height.
• Impact Platform: Area where the sample is positioned and struck.

Each component plays a vital role in generating consistent, repeatable test results.

Test Standards for Dart Impact Tester (ASTM D1709)

Dart impact testing is typically conducted in compliance with ASTM D1709, which includes:

• Method A: Utilizes a 38 mm diameter dart dropped from a height of 660 mm.
• Method B: Uses a 50 mm dart with a 1524 mm drop height.

The method is selected based on the material’s type, thickness, and usage. Accurate standardization ensures results are valid across different testing setups.

Step-by-Step Procedure to Use Dart Impact Tester

1. Sample Preparation

Begin by preparing plastic film samples that meet the test requirements. Ensure:

• Dimensions follow standards (commonly 150 mm × 150 mm)
• Samples are flat and wrinkle-free
• Surfaces are clean, dry, and free from defects

Condition samples to room temperature (usually 23°C ± 2°C) for 24 hours before testing.

2. Mount the Sample

• Place the sample centrally on the clamping fixture.
• Use the pneumatic or manual clamp (depending on model) to hold the film firmly.
• Avoid slack, wrinkles, or folds to maintain consistent impact.

Proper sample positioning is critical for accuracy.

3. Select Dart Type and Load Weights

• Choose the dart type (A or B) based on the material and standard.
• Start with a base weight and gradually increase or decrease based on the outcome of each test.
• Common incremental weight changes: 5 grams or 15 grams.

Attach weights carefully to avoid imbalance.

4. Set the Drop Height

• Set the height as per the selected test method.
  • Method A: 660 mm
  • Method B: 1524 mm
• Use the locking mechanism to fix the dart in position.
• Verify height from the scale to ensure compliance.

Drop height accuracy directly affects test validity.

5. Execute the Test

• Release the dart using the release lever.
• Observe whether the film sample ruptures or withstands the impact.
• Record the result as either:
  • Pass: No rupture
  • Fail: Rupture or visible damage

Use safety gear and avoid placing hands near the dart path.

6. Analyze and Document Results

• Conduct multiple drops (typically 20) to establish an average failure point.
• Use the Bruceton Staircase Method or Probit Analysis to determine mean failure weight.
• Record each result along with sample number, weight used, and result status.

The mean failure weight represents the impact strength of the material.

Factors That Influence Dart Impact Test Accuracy

To ensure reliable results, control the following:

• Temperature and Humidity: Maintain testing environment as per standards.
• Film Thickness: Ensure uniformity in all test samples.
• Operator Skill: Only trained personnel should conduct tests.
• Equipment Calibration: Regular calibration improves result consistency.

Dart Tip Condition: A worn or deformed dart can yield misleading outcomes.

Applications of Dart Impact Tester in Industry

The Dart Impact Test is essential in multiple sectors:

• Flexible Packaging: Verifies durability of LDPE and HDPE films.
• Food Packaging: Ensures frozen and vacuum-sealed packaging withstands impact.
• Medical & Pharmaceutical: Protects sterile packaging integrity.
• Agro Films: Tests greenhouse films and agricultural wraps.
• Industrial Packaging: Assesses strength of heavy-duty liners, sacks, and sheets.

As a dart impact tester manufacturer, Pacorr supports various industries by offering models tailored to unique testing demands.

Advantages of Using Pacorr Dart Impact Tester

• Precision Testing: Highly accurate results aligned with ASTM standards
• Sturdy Design: Durable frame for long-term performance
• Modular Weights: Easy customization for different impact energy levels
• User-Friendly Controls: Suitable for both beginner and advanced operators
• Reliable Support: Training, installation, and calibration guidance available

Pacorr ensures every dart impact tester is built for performance, accuracy, and compliance.

Maintenance and Calibration Checklist

To keep the instrument in top shape:

• Clean the dart head regularly after use.
• Check clamping unit for wear or loose fittings.
• Lubricate moving parts if needed (as per manual).
• Recalibrate weights and height scale every quarter.
• Keep a calibration logbook for audit trails.

Preventive maintenance boosts equipment life and maintains testing credibility.

Conclusion: Boost Quality Control with Pacorr Dart Impact Tester

The Pacorr Dart Impact Tester empowers industries to conduct reliable, repeatable impact strength tests that comply with international standards. By following the step-by-step guide, quality engineers and lab technicians can ensure that every packaging film, liner, or plastic sheet is tested precisely and efficiently.

Whether you're evaluating new packaging materials or validating production consistency, choosing a trusted dart impact tester manufacturer like Pacorr ensures long-term quality assurance and testing success.