1. Classification by Drive Mechanism

One of the most common ways to classify Universal Testing Machines (UTMs) is based on the drive system that applies force during testing. Each type is suited for specific test ranges and applications.

1.1. Electro-Mechanical (Electronic) UTM

This type uses a servo motor and a screw-driven mechanism to move the crosshead. It is commonly used for low- to medium-capacity testing (1kN to 100kN) and is ideal for materials like plastics, rubber, textiles, and thin metals.

Features:

• High precision and repeatability

• Quiet operation

• Suitable for tension, compression, and flexural tests

• Best for laboratory and quality control environments

1.2. Hydraulic UTM

Hydraulic UTMs are driven by a hydraulic power pack that generates force using oil pressure. These machines are designed for high-capacity testing, from 300kN to 2000kN or more.

Features:

• High force range

• Robust structure for heavy materials

• Ideal for metals, concrete, and construction materials

• Often used in industrial and research applications

1.3. Servo-Hydraulic UTM

This is an advanced form of hydraulic UTM with servo valves and digital controllers that provide dynamic load control. They are often used for fatigue and dynamic loading tests.

Features:

• High precision under cyclic loading

• Supports fatigue, crack growth, and high-speed tests

• Suitable for aerospace and automotive R&D

2. Classification by Frame Design

The physical configuration of the UTM also determines its functionality and test capability.

2.1. Single Column UTM

• Used for low-capacity testing (below 5kN)

• Compact design for benchtop use

• Suitable for film, foil, rubber, and paper

2.2. Dual Column UTM

• Rigid frame supports higher loads (up to 600kN)

• Provides better alignment and stability

• Suitable for plastics, metals, and composites

2.3. Four Column (Floor Type) UTM

• Used in large-capacity hydraulic systems

• Heavy-duty testing of steel, concrete, and large components

• Provides maximum stability and resistance to deformation

3. Classification by Function and Application

3.1. Static Testing Machines

These UTMs apply load at a constant speed to measure tensile, compressive, flexural, or shear properties. Most standard tests fall under this category.

Applications:

• Tensile testing of metals (ASTM E8, ISO 6892)

• Compression testing of concrete (ASTM C39, EN 12390-3)

• Flexural testing of plastics (ISO 178)

3.2. Fatigue Testing Machines

Designed to apply cyclic loads to evaluate how materials behave under repeated stress over time.

Applications:

• High-cycle fatigue tests for metal alloys

• Crack propagation studies

• Used in aerospace, automotive, and biomedical engineering

3.3. High-Temperature UTMs

Equipped with furnaces or environmental chambers to test material properties under elevated temperatures.

Applications:

• Creep and stress rupture tests

• Thermal fatigue testing

• Ideal for materials used in turbines, engines, and power plants