How Does a Universal Testing Machine Work? Understanding Its Components and Operating Principles

What is a Universal Testing Machine (UTM)?

A universal testing machine, or UTM, is a device that is used to test the mechanical properties of materials, such as tensile strength, compression, and bending. It is called universal because it can perform a wide range of tests on different materials, ranging from plastics to rubber and concrete.

The machine applies precise, controlled force and displacement to gauge a material’s mechanical properties and behaviour. This universal tester is used for the material’s compression test, tensile tester, modulus of elasticity test, and much more.

Main Components of a Universal Testing Machine

You need to become familiar with the main components of a universal testing machine to understand how the machine works:

Load Frame

The load frame is the backbone of the universal testing machine. It houses all the moving parts and provides stability to the machine when it is in use. The load frame holds the crosshead, which is a key component that applies stress to the material that you want to test.

It is generally made of steel or aluminium to ensure that it can handle extreme forces during tests.

Crosshead

The crosshead is divided into an upper and lower crosshead. The upper crosshead is stable and includes the actuator and load cell. Conversely, the lower crosshead moves and adjusts the height and clamping of the test specimen. The crosshead applies force to the test specimen to test its tensile strength or compressive strength. The precise movement of this component results in accurate results, thus providing valuable data.

Actuator

The actuator controls the crosshead’s movement. There are three types of actuators: hydraulic, pneumatic, and electromechanical. The actuators have different capabilities and, based on their specifications, are perfect for different applications. For instance, the hydraulic actuator is best for heavy-duty appliances.

Grips and Fixtures

The grips and fixtures hold the specimen securely in the designated place. Their main purpose is to ensure that the specimen is placed properly and is stable during testing. The types of grips and fixtures that are used depend on the tests performed.

Load Cell

The load cell measures the force applied to the specimen and converts it into electrical signals. These electrical signals are then monitored and recorded to determine the mechanical properties.

Extensometers

The extensometers calculate the specimen’s different mechanical properties, such as elongation and elasticity modulus. They come in various designs, ranging from non-contact types to clip-ons.

Control Unit

The test parameters are set in the control unit. The parameters range from load rate to test duration and desired force. It has a hydraulic power unit that sends pressure to the crossheads.

It also has a load-measuring unit that displays the amount of force applied. In modern times, the control unit is often computerised, which means you can test and analyse the data in real-time.

Operating Principles of a Universal Testing Machine

The basic functioning of the UTM is to provide controlled force to the specimen and to record how it responds to the force. Here is a step-by-step process of how it works:

Step 1 – Sample Preparation and Clamping

The first step in operating the UTM is preparing the sample and clamping it securely. The sample is usually prepared according to the standards set by ISO or ASTM.

Once the specimen is prepared, it is clamped using fixtures and clamps. At this point, it is essential to ensure that the material doesn’t slip and is aligned for proper force distribution. Any misalignment will lead to skewed results and impact the overall outcome of the test.

In this testing process, once the specimen is clamped, the UTM can apply force and proceed with the test.

Step 2 – Applying the Load

The machine will apply force after the specimen is clamped and properly aligned. The force may be tensile, compressive, or any other, depending on the type of test you want to perform. The actuator of the UTM controls the crosshead that applies force to the specimen.

It follows a predetermined load rate, and the UTM applies pressure precisely while increasing it simultaneously at a controlled rate to determine how the material deforms or reacts to stress.

The load cell measures the force applied, and the extensometer measures and tracks the deformation caused to the specimen.

Step 3 – Measuring the Material’s Response

While the UTM applies the pressure, the load cell and extensometer play their respective roles. The load cell measures the force applied, and the extensometer measures the specimen’s response to the force.

For example, the test is done to determine the specimen’s tensile strength and measure how it elongates with increased force. Now, the extensometer collects data regarding the material’s properties. In the meantime, the load cell records the applied load in real-time.

The two key players help measure the overall strength and properties of the specimen, which is crucial for further analysis.

Step 4 – Data Analysis and Reporting

Once the load cell and extensometer record the data, it is time to analyse it. This is the final step in operating a UTM.

In this step, you can understand the material’s mechanical properties and how it performs under stress. Computerised UTMs have advanced software that automatically compiles all the data and displays them as graphs.

Understanding the characteristics of a material is very important, as it helps optimise its usage while keeping in mind its safety and durability.

Choosing a Reliable UTM for Material Testing

At Test Machines, we understand the need to find reliable equipment for testing a material’s properties. This is why we offer high-tech UTMs for precise testing and accurate results.

Our tools are designed to meet all your needs and are easy to operate. Whether you want to test a material’s tensile strength or compression capabilities, our tools are your best choice.

Contact Test Machines today for the most durable and efficient universal testing machine.

TM-EML-Dual-Column Floor-Standing Universal Testing System

The TM-EML-Dual-Column Floor-Standing Universal Testing System is your choice if you are looking for a high-performance machine that precisely measures the characteristics of the material.

The machine’s capacity ranges from 50 kN to 600 kN and is used for testing different materials, building components, wood products, and composites.

The UTM offers high performance, reliability, long-term durability, and accurate results. It also has an advanced control system that includes USB 2.0 communication for real-time data exchange and monitoring.

All these qualities make the machine a suitable option for reliable testing.

How UTMs Work and Why They Matters

UTM, or materials testing machine, applies controlled force to test the characteristics of the specimen. It tests how the material responds to the force applied by the machine. The force applied may include measuring the tensile strength, compressive strength, or any other properties.

UTM matters because it can test the properties of the material. This helps in quality control and ensures that it is safe and durable for various purposes.

Conclusion 

A UTM serves a very crucial purpose. It can accurately track the characteristics of a material and help you optimise its usage. If you are looking for a reliable machine, Test Machines is your choice.

Contact us today to learn more.