UNIVERSAL TESTING MACHINE

A universal testing machine, often known as a UTM machine, is a kind of testing machine that applies a tensile, compressive, and transverse load on a sample in order to determine the mechanical characteristics of that material. A universal testing machine can perform a variety of tests by only requiring the user to change the grips and fasteners that are attached to it. Metals, concrete, rubber, and textiles are some of the materials that may be tested using this machine.  

UTM machine: Components 

 A universal testing machine is made up of two primary components, which are as follows:

• Loading Unit

Within the loading unit, both the configuration of the test sample and the application of the load are maintained. The following items make up the various parts of a UTM loading unit:

• Load Frame

Universal testing machines may have a single- or double-supported load frame, depending on the requirements of the test. The compression test sample is placed on a table, which is part of the load Frame’s upper crosshead. The lower crosshead is also a part of the load Frame.

• Lower Crosshead and Upper Crosshead

In order to secure one side of the test sample, the upper crosshead is often used. The load frame has a moveable crosshead that may be adjusted in height by loosening the crosshead’s screws. There’s a central notch that tapers on both crossheads. This opening has a set of racking jaws designed to secure and retain the tensile test sample.

• Elongation Scale

A scale that measures elongation is included with the loading unit, and it is used to determine how far the lower table has moved in relation to the top table.

• Control Unit

The control unit is the source of the information used to determine the changes in the load application and the related test result. The following are the primary elements that make up the control unit of a universal testing machine:

• Hydraulic Power Unit

The load unit’s primary cylinder receives constant oil pressure from the unit’s oil pump. This motion aids in the uniform loading of the specimen. An electric motor and a sump provide the power for the operation of an oil pump that is part of a hydraulic power unit.

• Load Measuring Unit

This device is equipped with a pendulum dynamometer, which consists of a small barrel with a piston that works in sync with the steady flow of oil. The piston and pendulum are linked by a pivoting lever. If you apply enough force to the specimen, the pivot lever will bend. The amount of load shown on the dial is determined by the amount by which the pointer is displaced.

• Control Devices

Both electrical and hydraulic systems may be used for the controls. Switches on the unit’s electric controls allow for vertical and horizontal crosshead movement. The Right Control Valve and also the Left Control Valve are the two halves of any hydraulic control system. For the purpose of applying stress on the sample, a right control valve is employed. Withdrawing pressure is accomplished by turning the control knob to the left.

UTM machine: Types

UTM machine: Uses

The following are just some of the most prevalent applications for UTMs:

• Tensile testing 

A tensile test is among the most typical uses of UTM, and it involves pulling a material apart until it breaks. This helps determine the material’s strength, how much it can be stretched, and how rigid it is.

• Compression testing 

A tensile test’s polar opposite is a compression test. A universal testing machine may be used to squeeze an item until it reaches a certain density, travels a certain distance, or cracks.

• Peel testing

The average peel force of a material may be determined by performing a test called a “peel test,” which is similar to a “tensile test” but involves separating two materials that were previously bonded together.

• Bend testing

In a bend test, the span of material is held at both ends while the machine exerts a force in the centre of the span until the material either breaks or travels a predetermined distance. The flexural strength and flexural modulus of a material are determined through bending tests.

• Puncture testing 

In order to determine a material sample’s level of resistance to being punctured during a puncture test, the sample is prodded until it is punctured.