Product testing is the backbone of quality control in engineering and manufacturing, ensuring products are reliable, durable, and safe before reaching the market. Over the years, the testing processes have evolved dramatically, transitioning from manual inspections to highly sophisticated automated systems. This article will explore how product testing has advanced, focusing on the evolution of testing machines, the role of data analytics (like MS Excel), and how modern standards such as ASTM and ICC-ES Acceptance Criteria influence today’s rigorous testing environments.
Industry Standards and Criteria Development
Organizations like ASTM International, ICC-ES, and ISO have been pivotal in developing testing standards and criteria. ASTM develops and publishes technical standards for a wide range of materials and products, setting the baseline for how tests should be conducted. These standards ensure consistency across the industry, allowing manufacturers to meet internationally recognized benchmarks for product quality.
The ICC-ES Acceptance Criteria is another set of guidelines that provide a basis for testing innovative products that may not yet have established testing protocols. These criteria allow for flexibility while ensuring that new products still meet rigorous safety and performance standards.
Early Days of Product Testing
In the early 20th century, product testing was predominantly manual and labor-intensive. Engineers relied on visual inspections and rudimentary mechanical tests using basic machines like tension testers and compression testing rigs. These machines were relatively simple—often hand-cranked—and measured basic properties like tensile strength, compression, and load-bearing capacity.
One example of early testing machines was The Little Giant by Tinius Olsen, which could test materials under tension, compression, and bending. These machines laid the foundation for more complex testing techniques and standards such as ASTM E8, which is the oldest standard for metal testing that is still in use today.
Evolution of Testing Machines and Standards
As manufacturing scaled up in the mid-20th century, so did the need for more precise testing. Mechanical testing machines became motorized, allowing for more consistent force application. Over time, electronic controls were introduced, improving accuracy and repeatability. Early machines operated using simple load gauges, but the development of strain gauge-based testing systems in the 1950s allowed for more accurate measurements of material deformation and stress.
The introduction of digital control systems in the 1970s revolutionized product testing. Machines could now be programmed to perform complex tests automatically, allowing for precise control over testing conditions like cyclic loading and displacement control. Cyclic loading, for example, simulates repeated stresses on materials to evaluate fatigue life—a crucial test for products exposed to constant forces, like bridges or aircraft wings. This advancement led to new testing standards for cyclic loading such as ASTM E2126. Displacement control testing, on the other hand, maintains a constant deformation rate, measuring how a material reacts over time under a controlled strain, which is essential for materials like steel and concrete. This allowed standards such as ASTM D7147 to include cross head rates for testing.
Durability Testing for Corrosion
In parallel with mechanical testing, the industry developed durability tests to ensure products could withstand environmental conditions. Corrosion testing, for instance, became essential for materials exposed to the elements. Salt spray chambers simulate corrosive environments to measure how materials like steel and aluminum degrade over time which led to the creation of ASTM B117 to standardize salt spray testing.
Data Analytics and the Role of MS Excel
The introduction of computers to testing labs in the 1980s dramatically improved the ability to analyze test data. Programs like MS Excel became vital tools for engineers. Data from mechanical and environmental tests could now be recorded, processed, and analyzed efficiently. Engineers could use Excel to create detailed reports, graph trends, and identify patterns in test results, vastly improving the decision-making process.
In particular, pivot tables and macros allowed for more advanced analysis, reducing human error and enabling the processing of larger datasets. As a result, Excel enabled engineers to correlate test results with product failures, leading to improvements in design and manufacturing processes.
Simulation Software and Real-World Testing
As computers became more powerful, simulation software started to replace some physical tests. Programs like ANSYS, SOLIDWORKS Simulation, and Autodesk allowed engineers to model products digitally and simulate how they would perform under various conditions, including mechanical stress, heat, and pressure. These simulations are typically based on real-world test data, enabling the software to replicate physical phenomena with increasing accuracy.
While simulation testing has reduced the need for extensive physical prototypes, it is typically used in conjunction with real-world testing to validate the models. Physical tests remain essential for verifying the assumptions and inputs used in simulations, ensuring that the digital models reflect real-world behavior.
Scaling Effects and Material Testing Precision
As product testing has evolved, so too has the understanding of scaling effects—how a product’s behavior under stress or load changes with its size. In structural testing, the impact of scaling is critical, especially when testing components that will be scaled up or down from the prototype stage. Engineers have found that certain materials or configurations behave differently when tested in small samples versus full-scale implementations, affecting measurements like tensile strength, compression resistance, and fatigue life. The advent of advanced simulation software has aided in addressing these scaling effects, enabling engineers to predict performance changes based on size adjustments.
Calibration and Accuracy in Testing Machines
Today, calibration of testing machines is a critical aspect of ensuring accurate results. Equipment must be regularly calibrated against known standards to guarantee precision. For example, load cells in modern testing machines are calibrated to ensure that force measurements are accurate to within specific tolerances, often governed by standards like those from ASTM E74.
Conclusion
Product testing has come a long way from manual inspections and simple mechanical tests. Today, testing is a complex process involving cutting-edge machines, data analytics, simulation software, and rigorous standards. As industries continue to evolve, so will the methods of testing—driven by the need for ever-greater precision and reliability in the products we use every day.
For additional information, or if you have questions, please contact the MiTek Research and Development or the MiTek Engineering department.