Comparing Platen Movement in Carton Compression Strength Testers

As a user researching carton compression strength tester, you might encounter different specifications related to the movement of the platens, the surfaces that apply the compressive force to the carton. Understanding these differences in platen movement can help you choose a tester that meets your specific testing requirements and ensures accurate and reliable results. This article breaks down the key variations in how platens move in carton compression strength testers.
 

One of the primary distinctions lies in the direction of platen movement. You might ask: "Which platen moves during the test?"

Single Moving Platen (Most Common): In most carton compression strength testers, one platen (typically the top platen) moves downwards to apply the compressive force, while the bottom platen remains stationary. This simulates the force of gravity acting on stacked cartons.
 

Dual Moving Platens (Less Common): Some advanced testers might have both the top and bottom platens moving towards each other to apply the compressive force. This can be useful for specific research applications or for testing materials under more complex compression scenarios.
 

You might also be curious about the control of the platen movement. You might ask: "How is the speed and force of the platen controlled?"

Constant Rate of Traverse (CRT): This is the most common method, where the movable platen travels at a constant speed towards the stationary platen. This ensures a consistent rate of compression throughout the test, allowing for reproducible results and compliance with many testing standards like ASTM D642.
 

Constant Rate of Loading (CRL): In this method, the tester controls the rate at which the compressive force is applied to the carton. The platen speed adjusts automatically to maintain the desired rate of force increase. This can be useful for understanding the material's response to a gradually increasing load.
 

Constant Position/Deflection: Some tests might involve moving the platen to a specific position or achieving a certain amount of carton deformation and holding it there for a specified time to assess creep or long-term compression effects.
 

Another important difference is the alignment and parallelism of the platens. You might ask: "Why is it important for the platens to be aligned?" Proper alignment and parallelism of the platens are crucial for ensuring that the compressive force is applied uniformly across the top surface of the carton. Misaligned platens can lead to uneven stress distribution and inaccurate test results, potentially underestimating the carton's true compression strength. High-quality carton compression strength testers will have mechanisms to ensure and maintain platen alignment.
 

The size and surface of the platens can also vary depending on the tester's capacity and intended use. You might ask: "Do the size and surface of the platens matter?" The platens should be large enough to cover the entire top or bottom surface of the cartons being tested to ensure uniform force application. The surface should be smooth and rigid to prevent slippage or deformation that could affect the test results.
 

Finally, advanced carton compression strength testers might offer features like programmable test sequences, allowing you to define complex compression profiles involving multiple stages of loading, unloading, and holding. These features provide a more comprehensive analysis of the carton's performance under various simulated conditions.
 

Understanding these differences in platen movement and control in carton compression strength testers is essential for selecting the right equipment for your needs. Consider the types of tests you need to perform, the standards you need to comply with, and the level of control and automation required to ensure accurate and meaningful results for your packaging performance evaluation.