Secure Seal Tester: Working Principle, Test Procedure, & Benefits

Proper container sealing is extremely important in the food, drink, medicine, cosmetics, and chemical industries. Proper sealing keeps the product fresh and safe for a longer period and makes customers happy. Weak or compromised seals can lead to contamination, spoilage, or leakage, resulting in financial losses and damage to brand reputation.

Secure Seal Testers help test whether the seal is tight by forcing air into the container (positive pressure) or removing air (vacuum). It functions by either applying internal pressure or a vacuum to the closed container and then checking for a change in pressure. Depending on the testing procedure, if the pressure drops or rises, it indicates that the container's seal is broken and leaking.

What is a Secure Seal Tester?

A Secure Seal Tester is a precision instrument used in industries to assess the strength and integrity of package seals. It applies controlled air pressure to detect leaks, weak seals, or seal failures. This helps ensure that packaging can withstand transportation, storage, and handling without compromising product safety.

Widely used in food, pharmaceutical, and consumer goods manufacturing, the tester plays a key role in quality control and regulatory compliance.

How does a secure seal tester work?

A secure seal tester checks whether a container’s seal is airtight or watertight by applying internal pressure or creating a vacuum around the package. If the seal is intact, the pressure remains stable throughout the test. However, if there's a leak or weak seal, the pressure will drop, indicating a failure. Below are the steps describing how a secure seal tester operates:

Step 1: Prepare the Sample: Insert the sealed package (such as a bottle, pouch, or can) into the tester.

Step 2: Use pressure or vacuum: Depending on the arrangement, either fill the vessel with air (positive pressure) or extract the air surrounding it (vacuum).

Step 3: Seal and Retain: The system seals and retains the applied pressure for a designated duration.

Step 4: Inspect for Change: Sensors within the tester monitor the pressure level during the retention time with great caution.

Step 5: Detect Leaks: If the pressure remains, the seal is tight. If it decreases, the seal is weak, or there is a leak.

Step 6: Record Results: The tester provides either a pass or fail reading, with information such as how much pressure was lost.

Secure seal tester working principle

A Secure Seal Tester operates on the principle of pressure fluctuation in a sealed package to identify a leak. The machine detects any pressure fluctuation by creating a vacuum or measuring pressure. It provides positive pressure (pushing air in) or negative pressure (vacuum) and tests whether the pressure is stable. If a leak or loose seal exists, the pressure will decrease or vacillate, indicating a weakened seal.

Secure Seal Test: A Step-by-step Procedure

A Secure seal test determines whether the seal is leak-tight and retains integrity at pressure. The following is a step-by-step procedure for a typical secure seal test.

Step 1: Preparation

• Check the test equipment: Confirm the Secure Seal Tester (or leak tester) is clean, calibrated, and functioning.

• Collect samples: Choose the sealed packages or containers you wish to test. Unless otherwise indicated, keep them at room temperature.

Step 2: Prepare the Tester

• Fill the tester with water (if using a water-based vacuum system) to the level indicated.
• Adjust settings: Set the test pressure desired based on your packaging requirements.

Step 3: Sample Placement

• Securely clamp the sample onto the tester fixture (e.g., sealing plate, chuck, or collar), making a snug fit without distorting the seal.
• Submerge the sample (if it is a vacuum tank type) or place it in the proper position under the test hood if it is a dry tester.

Step 4: Vacuum Application

• Gradually apply the set pressure (internal or external, as appropriate for the method) to the sample.
• Keep the pressure up for the specified hold time (usually 30 seconds to a few minutes, depending on your standard).

Step 5: Observation

• Observe for Leaks: Be aware of steady streams of bubbles (in aqueous systems) or pressure loss (in dry systems).
• Inspect seal areas: Closely observe closures, seams, and seals.

Step 6: Test Conclusion

• Let the pressure off slowly to prevent unnecessary damage to the sample.
• Carefully remove the sample from the fixture.

Step 7: Record Results

• Record: Pass or fail against predetermined acceptance criteria (no leak, bubble stream, or pressure drop outside of limit).
• Record: Sample ID, date, operator name, pressure applied, time held, and observations.
   

Benefits of using a secure seal tester for glass bottles

Using a secure seal tester for glass bottles prevents them from being opened, ensuring that nothing leaks or contaminates. It also identifies any seal problems at an early stage, reducing wastage and keeping customers satisfied. It generally enhances the quality of packaging.

1. Ensure Product Integrity

A seal tester protects the glass bottle from being poorly sealed, allowing the product inside to stay safe. It prevents air, water, or bacteria from coming in, and the product stays fresh and safe for a longer period. This guarantees the product is of its original quality from the production line to the hands of the consumer.

2. Prevent Leakage and Contamination

Leakage may result in product loss and contamination risks. Manufacturers can use a safe seal tester to identify weak seals in advance. Testing verifies that liquids remain within the bottle, eliminating spills, spoilage, and health risks. A strong seal also shields the product from harmful external contaminants.

3. Enhances Packaging Quality

Regular seal testing assures manufacturers of maintaining high packaging levels. Verifying that all batches of bottles meet quality standards prevents variability and faults. Better, consistent, strong seals improve the bottle's appearance, add strength, and extend shelf life, making it more reliable and appealing to buy.

4. Reduce Waste and Production Cost

Early detection of sealing issues prevents mass production failures. Faulty products can be repaired or recalled before shipping, conserving material, labor, and shipping expenses. Minimizing product recalls and returns also reduces monetary losses and assists the company in managing resources better.

5. Creates Consumer Confidence

When customers are shipped products in tightly sealed bottles, they feel the brand is secure and reliable. Well-sealed bottles always provide a satisfied customer experience that leads to repurchases and brand loyalty.

Conclusion

A safe seal tester is used to test the seals' strength and quality on glass bottles. The tester identifies leaks or weak seals easily with controlled pressure. A step-by-step operation provides precise results. It enhances product safety and packaging quality, saves waste, and increases customer confidence.

Presto Instruments is a leading tensile strength tester manufacturer in Sri Lanka, committed to global quality standards. Our equipment is designed to improve product reliability, reduce defects, and ensure consistent performance. Trusted by industries worldwide, we offer reliable and customized solutions to meet your testing needs. Contact us today.